Water model experiments on bubble motion and bubbly flows in a gas-liquid-liquid multiphase reactor

Water model experiments on bubble motion and bubbly flows in a gas-liquid-liquid multiphase reactor | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Water model experiments on bubble motion and bubbly flows in a gas-liquid-liquid multiphase reactor Shengnan Wang, Jie Wang, Wei Wang, Xiaoyi Cai, Hongliang Zhao, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4447533/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract A water model of a bottom-blown system has been established for investigating the bubble rising characteristic from one liquid phase to another, and also to probe the liquid-liquid interfacial movement with bubble crossing. Bubble shape and its influence on the interface are studied using wetting and non-wetting nozzles, respectively. Larger-size bubbles are formed from wetting nozzles which enhanced the liquid-liquid interface fluctuation. With the use of a double-nozzle injection gas, a too-small inter-hole distance will promote the bubble coalescence and form larger-size bubbles, and appropriately controlling the inter-hole distance can improve the slag-metal mixing and transfer. bottom blown wetting gas-liquid-liquid multiphase flow bubble Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 1 Introduction During the metallurgic production process, injection is widely used in the converting course to improve the mass transfer and chemical reactions of slag-metal systems and thereby enhance smelting efficiency (Dayal et al. 2006 ; Lin et al. 2012 ; Iguchi et al. 1994 ; Yamashita et al. 2003 ). The gas-liquid-liquid reaction system is ubiquitous in diverse smelting courses, including steel (Kochi et al. 2011 ), nonferrous (Sahai et al. 1982) and secondary resources (Natsui et al. 2014 ). The performance of gas-liquid reactors is largely affected by bubble formation, bubble velocity in liquid, and bubble fracture & coalescence (Natsui et al. 2014 ). The geometry of the bubble and the velocity of the bubble can be significantly different in different liquids. Furthermore, the behaviors of bubble formation decide the initial bubble size in the gas-liquid-liquid reaction system. Larger-size bubbles more rapidly rise above in the gas-liquid-liquid reaction system, which more severely affects the liquid-liquid interface. The bubble velocity in the liquid also decides the interphase contact time and thereby the interphase transfer. Therefore, it is of theoretical and practical significance to studying the intra-liquid behaviors of bubbles. Many experts and scholars have studied the influencing factors such as bubble shape, bubble movement speed, bubble entrainment, and summarised the corresponding rules. Grace ( 1973 ) indicated that the shape of the rising bubble is largely determined by the related dimensionless numbers, such as Reynolds number (Re), Weber number (We), and Morton number (Mo). Celata ( 2007 ) measured the bubble velocity in water. The rising velocity is mainly influenced by bubble size, deformation, liquid density, liquid viscosity and pressure. Reiter ( 1992 ) found that the bubble movement is affected by the liquid viscosity, interface fluctuation and previous entrainment when crossing the liquid-liquid interface. Dayal (2006) found when increasing the gas flow rate, the larger bubble with higher velocity may increase the interface fluctuation and affect the phase mass transfer. Farhadi (2022) found that the density, viscosity, and surface tension of the two liquids, as well as the diameter of the bubble, are valid parameters for the interaction between the bubble and the interface. By varying these variables, three main flow patterns are identified: penetration, entrainment, and envelopment. Zhou (2022) found that the main factors affecting the amount of bubble entrainment at the slag-metal interface are bubble diameter, followed by slag layer density. Mao (2020) focused on bubble behaviors as a bubble passes through the water-oil interface. The results indicated the bubble size is small in the mineral oil, and the intensity of the water jet varies with the size of the bubbles. Singh ( 2015 ) reported the effects of bubble diameter, interfacial tension, viscosity ratio and density difference on the phenomena (bubble retention time and bubble retention height) of a bubble passing through the liquid-liquid interface. Fundamental studies of the dynamics of bubble in fluids have contributed to a better understanding of bubble movement mechanisms. Wang ( 2022 ) investigated the dynamics of bubbles, both uncoated and covered by different levels of particles, interacting with an air-liquid interface, which contribute to the understanding of the dynamics of bubbles colliding with the air-liquid interface. Cao ( 2020 ) investigated the effect of initial bubble shape on bubble dynamics and studied the effects of density, viscosity ratios, initial bubble shape, and two inline bubbles on the central breakup behaviors. Choi ( 2021 ) explored the dynamics of a rising bubble and interfacial phenomena by varying the bubble size and the viscosity ratio of the liquids. Kulkarni ( 2005 ) believed that when a bubble impacted the liquid-liquid interface, the interface fracture will cause the entrainment of the lower phase to the upper phase. Ellingsen ( 2001 ) noted that there are two stages of rising bubble movement, one is a zigzag motion for initially unstable bubbles, and the other one is a spiral motion for stable bubbles. Su (2023) established a numerical analysis model for the interaction between the high-pressure bubble and the multiphase interface in the compressible viscous fluid based on the EFEM and found that the bubble only generates a downward jet at a large Reynolds number. Rabbani ( 2024 ) focused on the passage of single and two inline bubbles through the liquid-liquid interface. The study showed that bubbles after coalescence travel faster than that of a single bubble rising through the interface. For all bubble gaps, the velocity of the rear bubble is greater than that of the front bubble. To sum up, the influencing factors of bubble shape, velocity and entrainment have been more widely studied, and the dynamics of a rising bubble has been gradually improved. Among them, the influence of wettability and inter-hole distance on the bubbles movement in multiphase flow cannot be neglected. The objective of the present study is to describe the behavior of bubbles at different gas flow rates and to investigate the effect of wettability and inter-hole distance on bubble size, which leads to changes in the bubble rise rate in liquid-liquid systems and affects interfacial impact. With the conclusions obtained, it is expected to gain further insight into transient bubble behaviors near the liquid-liquid interface, which will modestly improve production efficiency. 2 Equipment and methods The schematic diagram of the experimental setup is shown in Fig. 1 . Specifically, an air compressor was used as the feed supply, and a decompression valve and a gas flow meter provided adjustable and stable injection gas. The main part of the injection model was made of organic glass and placed on metal supports. Some space was left between the vessel and the experiment platform, which facilitated the placement of bottom anti-recirculation control valves (Fig. 1 a). The self-made disassemble nozzle (Fig. 2 b) consisted of a single-hole nozzle, double-hole nozzle with different inter-hole distances, and a paraffin-coated nozzle model. The phases were: water was used as the lower-layer liquid phase that simulated the metal molten phase during smelting, and viscosity-variable silicon oil as the upper-layer liquid phase to simulate the slag phase. Specifically, its density, viscosity, and the oil-water interfacial tensions were detected. A high-speed camera was used to photograph the gas injection in liquid-liquid phases. During high-speed photography, the shutter could capture hundreds or even thousands of photos within a second, so the light entrance amount per frame was very small. To guarantee high-quality photography, two groups of cold light sources were used as irradiations. The water phase at the bottom was also stained to capture a clear liquid-liquid interface. 3 Results and discussion 3.1 Effects on single-pole gas flow rate Figure 2 shows the distributions of gas-oil-water phases against the gas flow rate. At a very small gas flow rate, the interfaces are impacted by small individual bubbles. The impacting frequency rises with the increase in gas flow rate. At the gas flow rate of 500, the bubbles enlarge, coalesce and break more frequently. After the compacting, a stable cylindrical oil-water interface is formed. When the gas flow rate further rises to 1500, the cylindrical interface destabilizes. At the flow rate up to 4000, the two phases mutually penetrate so the oil-water interface gradually disappears until they completely mix at the flow rate of 8000. Figure 3 shows the schematic diagram of entrainment height when the bubbles pass through the liquid-liquid interfaces at γ = 100 cSt( γ is the viscosity). At the gas flow rate of 20 mL/min, the entrainment height of bubbles on the lower liquid layer is about 1.4 cm, but it gradually rises with the increase in the gas flow rate. When the gas flow rate is up to 180 mL/min, the liquid-liquid interface fractures, so the bubbles carry the lower liquid layer, forming an upright rising water column, at which the entrainment height is 7 cm. The interfacial actions of bubbles appear in two areas: single-bubble action area, and double-bubble action area. The critical gas flow rate between these two areas is about 140 mL/min. Due to the increase of silicone oil viscosity, bubble coalescence, or interaction of two or three bubbles, occurred, leading to the enlargement of entrainment height from bubbles on the lower liquid layer in the first area. The single bubble rises in the second area, leading to a decrease in entrainment height. 3.2 Effects on wettability in single-pole experiments It was investigated how wettability affected the bubble size when the bubbles were raised under different gas flow rates, leading to variation in bubble velocity in the liquid-liquid system and affecting the interface impact (Fig. 4 ). The experimental conditions were: single-pole organic glass wet or non-wet nozzles, water phase height = 15 cm; oil phase height = 7 cm; gas flow rate Q = 60, 100, 500, 1000, 1500, 4167 mL/min; silicon oil viscosity = 100 cSt. The bubbles spouted out from the wet nozzle are larger in volume than those spouted from the non-wet nozzle, and with the rise of gas flow rate ( Q ≥ 4167 mL/min), the effect of wetness on bubble volume is weakened. Under the same gas flow rate and at the same time, the number of bubbles spouted out from the nozzle declines. Under wet conditions, the bubbles within a certain period after the blowout will rise in an approximately spherical way. The bubbles spouted out from the non-wet nozzle will rise in an approximately ellipsoid shape at a very small gas flow rate, but no fixed shape can be maintained at a high gas flow rate, so the bubbles fracture easily. Both bubble size and shape changed in comparison between wet and non-wet conditions. At the gas flow rate Q ≤ 1000 mL/min, the maximum bubble diameter under wet conditions is larger than that under non-wet conditions, but at Q > 1000 mL/min, the bubble diameter under non-wet conditions increases. Moreover, with the rise of the gas flow rate, the bubble shape develops to approximately a sphere under non-wet conditions. At a very large gas flow rate, the bubble shape under wet conditions develops to approximately a bullet shape. Figure 5 shows the schematic diagram of interfacial impact under both wet and non-wet conditions at different gas flow rates. Clearly, under wet conditions, the bubbles are large in volume. When they pass the liquid-liquid interface, the entrainment is very severe, which impacts the liquid-liquid interface and causes severe interfacial fluctuation. At a very large gas flow rate ( Q = 4167 mL/min), the effects of wetness on bubble volume and interfacial impact are weakened. 3.3 Effect on inter-hole distance in double-hole experiments Here we investigated how inter-hole distance affected the bubble size, leading to variation of bubble velocity in the liquid-liquid system and affecting the interfacial impact (Fig. 6 ). The experimental conditions were: double-hole organic glass, inter-hole distance = 2-, 4- and 8-fold hole diameter, water phase height = 15 cm; oil phase height = 7 cm; gas flow rate Q = 1500; silicon oil viscosity = 100 cSt. The photos of rising bubbles under inter-hole distance = 2-, 4- and 8-fold hole diameter were processed and the data were analyzed. (1) At the inter-hole distance = 2-fold hole diameter, the bubbles rising to 8 cm high will coalesce and after that, the velocity of the rising bubble suddenly increases, but it slightly decreases after the bubble shape stabilizes. The interfacial impact causes interfacial fluctuation, so the water phase and oil phase are mixed, affecting the rising of bubbles. The velocity of the rising bubble near the interface slightly declines and it gradually increases after passing the liquid-liquid interface and then stabilizes. (2) At the inter-hole distance = 4-fold hole diameter, the bubbles rising to 9.5 cm high will coalesce, where the bubble velocity is constant, but it starts to increase after the bubble shape stabilizes. The interfacial impact causes interfacial fluctuation, so the water phase and oil phase are mixed, affecting the rising of bubbles. The rising near the interface slightly declines and it gradually increases after passing the liquid-liquid interface and then stabilizes. Figure 7 shows the temporal changes of the bubble rising height with the inter-hole distance. Clearly, at the inter-hole distance of 8-fold diameter, the bubbles do not coalesce and the bubble velocity in the liquid phase does not change largely. Thus, the temporal changing curve is a straight line. Under the inter-hole distance of 4- and 2-fold hole diameter, the bubbles coalesce at different heights, and the bubble velocity is affected by coalescence and interface fluctuation. Consequently, the bubble rising height in the liquid phase does not change linearly with time. Figure 8 shows the coalescence of bubbles spouted from the inter-hole distance of 2-, 4- and 8-fold hole diameter at the gas flow rate Q = 1500 mL/min. Bubble coalesce is in the inter-hole distance of 2- and 4-fold hole diameter, but not in the inter-hole distance of 8-fold hole diameter. Bubble coalescence in the inter-hole distance of 2- and 4-fold hole diameter occurs at the rising height of 8 and 9.5 cm, respectively. Figure 9 shows the interfacial impact of bubbles spouted from the inter-hole distance of 2-, 4- and 8-fold hole diameter. Analysis of photos shows that with the rise of inter-hole distance, the impact on the liquid-liquid interface, the mixing between the water phase and oil phase, and the interface fluctuation are all reduced. The interfacial impact at the inter-hole distance of 2-fold hole diameter is the most significant. As shown on the interface fluctuation curves at the two inter-hole distances, the interface fluctuations at the inter-hole distances of 2- and 4-fold hole diameters are 2 and 0.5 cm, respectively. 4. Conclusions The present study focused on the bubble rising characteristic from one liquid phase to another one and the liquid-liquid interface movement with bubble crossing. A water model has been established for investigating the bubble rising characteristic from one liquid phase to another and the liquid-liquid interface movement with bubble crossing. Specifically, the effects of these parameters on the bubble velocity and the interface fluctuation are studied. The major conclusions obtained in this study are as follows: (1) The bubble velocity is affected by bubble size, bubble interaction and interface fluctuation. The bubble velocity rises with the increase in bubble size but declines during bubble rupture. The bubble coalescence increases the instantaneous bubble velocity. At a small gas flow rate, the bubble velocity near the liquid-liquid interface and passing through the interface declines. When the gas flow rate rises to a certain level, a water-phase channel appears in the upper-layer oil phase. At the flow rate up to 4000, the two phases mutually penetrate so the oil-water interface gradually disappears. At the flow rate up to 8000, the oil-water interface completely mixes, so the effect of the interface on the bubble velocity is weakened. The entrainment height of bubbles on the lower liquid layer increases gradually with increasing gas flow rate. The interfacial actions of gas bubbles appear as a single-bubble action area and a double-bubble action area. The critical gas flow rate between these two areas is about 140 mL/min. (2) Bubble size and shape change with airflow velocity in both humid and non-humid conditions. At the gas flow rate Q ≤ 1000 mL/min, the maximum bubble diameter under wet conditions is larger than that under non-wet conditions, but at Q > 1000 mL/min, the bubble diameter under non-wet conditions increases. Bubble coalescence is not in the inter-hole distance of 8-fold hole diameter. Therefore, the bubble rising height in 8-fold hole diameter varies linearly with time. Whereas, the bubbles coalesce at different heights in the inter-hole distance of 2-fold and 4-fold hole diameter, so the bubble rising heights do not vary linearly with time. The impact on the liquid-liquid interface and the impact on the interface fluctuation all decrease with the rise of the inter-hole distance. With the use of a double-nozzle injection gas, a too-small inter-hole distance will promote the bubble coalescence and form larger-size bubbles. Appropriately controlling the inter-hole distance can enlarge the interfacial impact, improve the slag-metal mixing, and promote the mass transfer and chemical reactions between slag and metals, thereby modestly improving smelting efficiency. (3) Under the same conditions, larger bubbles are formed under wet conditions. Experiments showed that under wet conditions, the bubble volume will increase, which more significantly impacts the liquid-liquid interface and intensifies the interface fluctuation. These changes facilitate the slag-metal mass transfer and chemical reactions, which will modestly improve production efficiency. Declarations Acknowledgments The authors are grateful for the financial supports from the National Key Research and Development Program of China (2022YFB3304901). Funding National Key Research and Development Program of China (2022YFB3304901). Conflicts of Interest The authors declare that they have no conflict of interest. Author Contribution Wang SN and Wang J wrote the main manuscript. Wang W prepared figures 1-5. Cai XY prepared figures 6-9. Zhao HL and Lv C supervised. All authors reviewed the manuscript. Data Availability Statement (Required) Data can be made available upon reasonable request. Informed consent N/A Ethical approval N/A References Cao, Y., Macián-Juan, R.: Numerical study of the central breakup behaviors of a large bubble rising in quiescent liquid. Chem. Eng. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-4447533","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":309457388,"identity":"d89745d7-0fea-404b-bead-31b931eb6639","order_by":0,"name":"Shengnan Wang","email":"","orcid":"","institution":"University of Science and Technology Beijing","correspondingAuthor":false,"prefix":"","firstName":"Shengnan","middleName":"","lastName":"Wang","suffix":""},{"id":309457389,"identity":"ae41c5d3-7742-4abb-b0c0-fd32f7bc69ed","order_by":1,"name":"Jie Wang","email":"","orcid":"","institution":"University of Science and Technology 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4","display":"","copyAsset":false,"role":"figure","size":1169683,"visible":true,"origin":"","legend":"\u003cp\u003eEffects of wetness on bubble size\u003c/p\u003e","description":"","filename":"Fig.4.png","url":"https://assets-eu.researchsquare.com/files/rs-4447533/v1/f2959195668f8449a2c55345.png"},{"id":57678956,"identity":"929a6325-c779-4eb3-be66-b0dc75fb0233","added_by":"auto","created_at":"2024-06-04 08:32:15","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":1789685,"visible":true,"origin":"","legend":"\u003cp\u003eEffects of wetness on interface impact.\u003c/p\u003e","description":"","filename":"Fig.5.png","url":"https://assets-eu.researchsquare.com/files/rs-4447533/v1/2ccffcc388a9f173d6211e2b.png"},{"id":57679425,"identity":"f98c51ce-9cfe-4142-b497-6a62d1036205","added_by":"auto","created_at":"2024-06-04 08:40:15","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":27022,"visible":true,"origin":"","legend":"\u003cp\u003eEffects of inter-hole distance on the bubble velocity\u003c/p\u003e","description":"","filename":"Fig.6.png","url":"https://assets-eu.researchsquare.com/files/rs-4447533/v1/f67e096ae36f7b73b485731a.png"},{"id":57678958,"identity":"b5043bdd-74f1-49d8-a5e6-ff02dccb7c60","added_by":"auto","created_at":"2024-06-04 08:32:15","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":11189,"visible":true,"origin":"","legend":"\u003cp\u003eTemporal change of bubble rising height\u003c/p\u003e","description":"","filename":"Fig.7.png","url":"https://assets-eu.researchsquare.com/files/rs-4447533/v1/57e877239128e4930270413e.png"},{"id":57678961,"identity":"63d4b503-89bd-4097-8569-aa721c2c93fa","added_by":"auto","created_at":"2024-06-04 08:32:16","extension":"png","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":204784,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eEffects of inter-hole distance on bubble coalescence\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"Fig.8.png","url":"https://assets-eu.researchsquare.com/files/rs-4447533/v1/7512b8bc9577f43f2b8ead59.png"},{"id":57678960,"identity":"8fcccff4-4246-4ac0-8838-50f9f6f17cf0","added_by":"auto","created_at":"2024-06-04 08:32:16","extension":"png","order_by":9,"title":"Figure 9","display":"","copyAsset":false,"role":"figure","size":170450,"visible":true,"origin":"","legend":"\u003cp\u003eInterfacial impacts at different inter-hole distances\u003c/p\u003e","description":"","filename":"Fig.9.png","url":"https://assets-eu.researchsquare.com/files/rs-4447533/v1/6a9f38464c8600c108bafa4f.png"},{"id":57996269,"identity":"8daf424d-5428-4b5f-a8e7-f0e02dc739af","added_by":"auto","created_at":"2024-06-09 09:31:33","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":11220652,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4447533/v1/29f82911-231c-4f1a-b343-a9a1293bb078.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Water model experiments on bubble motion and bubbly flows in a gas-liquid-liquid multiphase reactor","fulltext":[{"header":"1 Introduction","content":"\u003cp\u003eDuring the metallurgic production process, injection is widely used in the converting course to improve the mass transfer and chemical reactions of slag-metal systems and thereby enhance smelting efficiency (Dayal et al. \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e2006\u003c/span\u003e; Lin et al. \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e2012\u003c/span\u003e; Iguchi et al. \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e1994\u003c/span\u003e; Yamashita et al. \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e2003\u003c/span\u003e). The gas-liquid-liquid reaction system is ubiquitous in diverse smelting courses, including steel (Kochi et al. \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e2011\u003c/span\u003e), nonferrous (Sahai et al. 1982) and secondary resources (Natsui et al. \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e2014\u003c/span\u003e). The performance of gas-liquid reactors is largely affected by bubble formation, bubble velocity in liquid, and bubble fracture \u0026amp; coalescence (Natsui et al. \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e2014\u003c/span\u003e). The geometry of the bubble and the velocity of the bubble can be significantly different in different liquids. Furthermore, the behaviors of bubble formation decide the initial bubble size in the gas-liquid-liquid reaction system. Larger-size bubbles more rapidly rise above in the gas-liquid-liquid reaction system, which more severely affects the liquid-liquid interface. The bubble velocity in the liquid also decides the interphase contact time and thereby the interphase transfer. Therefore, it is of theoretical and practical significance to studying the intra-liquid behaviors of bubbles.\u003c/p\u003e \u003cp\u003eMany experts and scholars have studied the influencing factors such as bubble shape, bubble movement speed, bubble entrainment, and summarised the corresponding rules. Grace (\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e1973\u003c/span\u003e) indicated that the shape of the rising bubble is largely determined by the related dimensionless numbers, such as Reynolds number (Re), Weber number (We), and Morton number (Mo). Celata (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2007\u003c/span\u003e) measured the bubble velocity in water. The rising velocity is mainly influenced by bubble size, deformation, liquid density, liquid viscosity and pressure. Reiter (\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e1992\u003c/span\u003e) found that the bubble movement is affected by the liquid viscosity, interface fluctuation and previous entrainment when crossing the liquid-liquid interface. Dayal (2006) found when increasing the gas flow rate, the larger bubble with higher velocity may increase the interface fluctuation and affect the phase mass transfer. Farhadi (2022) found that the density, viscosity, and surface tension of the two liquids, as well as the diameter of the bubble, are valid parameters for the interaction between the bubble and the interface. By varying these variables, three main flow patterns are identified: penetration, entrainment, and envelopment. Zhou (2022) found that the main factors affecting the amount of bubble entrainment at the slag-metal interface are bubble diameter, followed by slag layer density. Mao (2020) focused on bubble behaviors as a bubble passes through the water-oil interface. The results indicated the bubble size is small in the mineral oil, and the intensity of the water jet varies with the size of the bubbles. Singh (\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e2015\u003c/span\u003e) reported the effects of bubble diameter, interfacial tension, viscosity ratio and density difference on the phenomena (bubble retention time and bubble retention height) of a bubble passing through the liquid-liquid interface.\u003c/p\u003e \u003cp\u003eFundamental studies of the dynamics of bubble in fluids have contributed to a better understanding of bubble movement mechanisms. Wang (\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2022\u003c/span\u003e) investigated the dynamics of bubbles, both uncoated and covered by different levels of particles, interacting with an air-liquid interface, which contribute to the understanding of the dynamics of bubbles colliding with the air-liquid interface. Cao (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e2020\u003c/span\u003e) investigated the effect of initial bubble shape on bubble dynamics and studied the effects of density, viscosity ratios, initial bubble shape, and two inline bubbles on the central breakup behaviors. Choi (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2021\u003c/span\u003e) explored the dynamics of a rising bubble and interfacial phenomena by varying the bubble size and the viscosity ratio of the liquids. Kulkarni (\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e2005\u003c/span\u003e) believed that when a bubble impacted the liquid-liquid interface, the interface fracture will cause the entrainment of the lower phase to the upper phase. Ellingsen (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e2001\u003c/span\u003e) noted that there are two stages of rising bubble movement, one is a zigzag motion for initially unstable bubbles, and the other one is a spiral motion for stable bubbles. Su (2023) established a numerical analysis model for the interaction between the high-pressure bubble and the multiphase interface in the compressible viscous fluid based on the EFEM and found that the bubble only generates a downward jet at a large Reynolds number. Rabbani (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e2024\u003c/span\u003e) focused on the passage of single and two inline bubbles through the liquid-liquid interface. The study showed that bubbles after coalescence travel faster than that of a single bubble rising through the interface. For all bubble gaps, the velocity of the rear bubble is greater than that of the front bubble.\u003c/p\u003e \u003cp\u003eTo sum up, the influencing factors of bubble shape, velocity and entrainment have been more widely studied, and the dynamics of a rising bubble has been gradually improved. Among them, the influence of wettability and inter-hole distance on the bubbles movement in multiphase flow cannot be neglected. The objective of the present study is to describe the behavior of bubbles at different gas flow rates and to investigate the effect of wettability and inter-hole distance on bubble size, which leads to changes in the bubble rise rate in liquid-liquid systems and affects interfacial impact. With the conclusions obtained, it is expected to gain further insight into transient bubble behaviors near the liquid-liquid interface, which will modestly improve production efficiency.\u003c/p\u003e"},{"header":"2 Equipment and methods","content":"\u003cp\u003eThe schematic diagram of the experimental setup is shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. Specifically, an air compressor was used as the feed supply, and a decompression valve and a gas flow meter provided adjustable and stable injection gas. The main part of the injection model was made of organic glass and placed on metal supports. Some space was left between the vessel and the experiment platform, which facilitated the placement of bottom anti-recirculation control valves (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ea). The self-made disassemble nozzle (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eb) consisted of a single-hole nozzle, double-hole nozzle with different inter-hole distances, and a paraffin-coated nozzle model.\u003c/p\u003e \u003cp\u003eThe phases were: water was used as the lower-layer liquid phase that simulated the metal molten phase during smelting, and viscosity-variable silicon oil as the upper-layer liquid phase to simulate the slag phase. Specifically, its density, viscosity, and the oil-water interfacial tensions were detected. A high-speed camera was used to photograph the gas injection in liquid-liquid phases. During high-speed photography, the shutter could capture hundreds or even thousands of photos within a second, so the light entrance amount per frame was very small. To guarantee high-quality photography, two groups of cold light sources were used as irradiations. The water phase at the bottom was also stained to capture a clear liquid-liquid interface.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e"},{"header":"3 Results and discussion","content":"\u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003e3.1 Effects on single-pole gas flow rate\u003c/h2\u003e \u003cp\u003eFigure\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e shows the distributions of gas-oil-water phases against the gas flow rate. At a very small gas flow rate, the interfaces are impacted by small individual bubbles. The impacting frequency rises with the increase in gas flow rate. At the gas flow rate of 500, the bubbles enlarge, coalesce and break more frequently. After the compacting, a stable cylindrical oil-water interface is formed. When the gas flow rate further rises to 1500, the cylindrical interface destabilizes. At the flow rate up to 4000, the two phases mutually penetrate so the oil-water interface gradually disappears until they completely mix at the flow rate of 8000.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eFigure\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e shows the schematic diagram of entrainment height when the bubbles pass through the liquid-liquid interfaces at \u003cem\u003eγ\u003c/em\u003e\u0026thinsp;=\u0026thinsp;100 cSt(\u003cem\u003eγ\u003c/em\u003e is the viscosity). At the gas flow rate of 20 mL/min, the entrainment height of bubbles on the lower liquid layer is about 1.4 cm, but it gradually rises with the increase in the gas flow rate. When the gas flow rate is up to 180 mL/min, the liquid-liquid interface fractures, so the bubbles carry the lower liquid layer, forming an upright rising water column, at which the entrainment height is 7 cm. The interfacial actions of bubbles appear in two areas: single-bubble action area, and double-bubble action area. The critical gas flow rate between these two areas is about 140 mL/min. Due to the increase of silicone oil viscosity, bubble coalescence, or interaction of two or three bubbles, occurred, leading to the enlargement of entrainment height from bubbles on the lower liquid layer in the first area. The single bubble rises in the second area, leading to a decrease in entrainment height.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003e3.2 Effects on wettability in single-pole experiments\u003c/h2\u003e \u003cp\u003eIt was investigated how wettability affected the bubble size when the bubbles were raised under different gas flow rates, leading to variation in bubble velocity in the liquid-liquid system and affecting the interface impact (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e). The experimental conditions were: single-pole organic glass wet or non-wet nozzles, water phase height\u0026thinsp;=\u0026thinsp;15 cm; oil phase height\u0026thinsp;=\u0026thinsp;7 cm; gas flow rate \u003cem\u003eQ\u003c/em\u003e\u0026thinsp;=\u0026thinsp;60, 100, 500, 1000, 1500, 4167 mL/min; silicon oil viscosity\u0026thinsp;=\u0026thinsp;100 cSt.\u003c/p\u003e \u003cp\u003eThe bubbles spouted out from the wet nozzle are larger in volume than those spouted from the non-wet nozzle, and with the rise of gas flow rate (\u003cem\u003eQ\u003c/em\u003e\u0026thinsp;\u0026ge;\u0026thinsp;4167 mL/min), the effect of wetness on bubble volume is weakened. Under the same gas flow rate and at the same time, the number of bubbles spouted out from the nozzle declines. Under wet conditions, the bubbles within a certain period after the blowout will rise in an approximately spherical way. The bubbles spouted out from the non-wet nozzle will rise in an approximately ellipsoid shape at a very small gas flow rate, but no fixed shape can be maintained at a high gas flow rate, so the bubbles fracture easily.\u003c/p\u003e \u003cp\u003eBoth bubble size and shape changed in comparison between wet and non-wet conditions. At the gas flow rate \u003cem\u003eQ\u003c/em\u003e\u0026thinsp;\u0026le;\u0026thinsp;1000 mL/min, the maximum bubble diameter under wet conditions is larger than that under non-wet conditions, but at \u003cem\u003eQ\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;1000 mL/min, the bubble diameter under non-wet conditions increases. Moreover, with the rise of the gas flow rate, the bubble shape develops to approximately a sphere under non-wet conditions. At a very large gas flow rate, the bubble shape under wet conditions develops to approximately a bullet shape.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eFigure\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e shows the schematic diagram of interfacial impact under both wet and non-wet conditions at different gas flow rates. Clearly, under wet conditions, the bubbles are large in volume. When they pass the liquid-liquid interface, the entrainment is very severe, which impacts the liquid-liquid interface and causes severe interfacial fluctuation. At a very large gas flow rate (\u003cem\u003eQ\u003c/em\u003e\u0026thinsp;=\u0026thinsp;4167 mL/min), the effects of wetness on bubble volume and interfacial impact are weakened.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003e3.3 Effect on inter-hole distance in double-hole experiments\u003c/h2\u003e \u003cp\u003eHere we investigated how inter-hole distance affected the bubble size, leading to variation of bubble velocity in the liquid-liquid system and affecting the interfacial impact (Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e). The experimental conditions were: double-hole organic glass, inter-hole distance\u0026thinsp;=\u0026thinsp;2-, 4- and 8-fold hole diameter, water phase height\u0026thinsp;=\u0026thinsp;15 cm; oil phase height\u0026thinsp;=\u0026thinsp;7 cm; gas flow rate \u003cem\u003eQ\u003c/em\u003e\u0026thinsp;=\u0026thinsp;1500; silicon oil viscosity\u0026thinsp;=\u0026thinsp;100 cSt.\u003c/p\u003e \u003cp\u003eThe photos of rising bubbles under inter-hole distance\u0026thinsp;=\u0026thinsp;2-, 4- and 8-fold hole diameter were processed and the data were analyzed.\u003c/p\u003e \u003cp\u003e(1) At the inter-hole distance\u0026thinsp;=\u0026thinsp;2-fold hole diameter, the bubbles rising to 8 cm high will coalesce and after that, the velocity of the rising bubble suddenly increases, but it slightly decreases after the bubble shape stabilizes. The interfacial impact causes interfacial fluctuation, so the water phase and oil phase are mixed, affecting the rising of bubbles. The velocity of the rising bubble near the interface slightly declines and it gradually increases after passing the liquid-liquid interface and then stabilizes.\u003c/p\u003e \u003cp\u003e(2) At the inter-hole distance\u0026thinsp;=\u0026thinsp;4-fold hole diameter, the bubbles rising to 9.5 cm high will coalesce, where the bubble velocity is constant, but it starts to increase after the bubble shape stabilizes. The interfacial impact causes interfacial fluctuation, so the water phase and oil phase are mixed, affecting the rising of bubbles. The rising near the interface slightly declines and it gradually increases after passing the liquid-liquid interface and then stabilizes.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eFigure\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e shows the temporal changes of the bubble rising height with the inter-hole distance. Clearly, at the inter-hole distance of 8-fold diameter, the bubbles do not coalesce and the bubble velocity in the liquid phase does not change largely. Thus, the temporal changing curve is a straight line. Under the inter-hole distance of 4- and 2-fold hole diameter, the bubbles coalesce at different heights, and the bubble velocity is affected by coalescence and interface fluctuation. Consequently, the bubble rising height in the liquid phase does not change linearly with time.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eFigure\u0026nbsp;\u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003e shows the coalescence of bubbles spouted from the inter-hole distance of 2-, 4- and 8-fold hole diameter at the gas flow rate \u003cem\u003eQ\u003c/em\u003e\u0026thinsp;=\u0026thinsp;1500 mL/min.\u003c/p\u003e \u003cp\u003eBubble coalesce is in the inter-hole distance of 2- and 4-fold hole diameter, but not in the inter-hole distance of 8-fold hole diameter. Bubble coalescence in the inter-hole distance of 2- and 4-fold hole diameter occurs at the rising height of 8 and 9.5 cm, respectively.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eFigure\u0026nbsp;\u003cspan refid=\"Fig9\" class=\"InternalRef\"\u003e9\u003c/span\u003e shows the interfacial impact of bubbles spouted from the inter-hole distance of 2-, 4- and 8-fold hole diameter. Analysis of photos shows that with the rise of inter-hole distance, the impact on the liquid-liquid interface, the mixing between the water phase and oil phase, and the interface fluctuation are all reduced. The interfacial impact at the inter-hole distance of 2-fold hole diameter is the most significant. As shown on the interface fluctuation curves at the two inter-hole distances, the interface fluctuations at the inter-hole distances of 2- and 4-fold hole diameters are 2 and 0.5 cm, respectively.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"4. Conclusions","content":"\u003cp\u003eThe present study focused on the bubble rising characteristic from one liquid phase to another one and the liquid-liquid interface movement with bubble crossing. A water model has been established for investigating the bubble rising characteristic from one liquid phase to another and the liquid-liquid interface movement with bubble crossing. Specifically, the effects of these parameters on the bubble velocity and the interface fluctuation are studied. The major conclusions obtained in this study are as follows:\u003c/p\u003e\n\u003cp\u003e(1) The bubble velocity is affected by bubble size, bubble interaction and interface fluctuation. The bubble velocity rises with the increase in bubble size but declines during bubble rupture. The bubble coalescence increases the instantaneous bubble velocity. At a small gas flow rate, the bubble velocity near the liquid-liquid interface and passing through the interface declines. When the gas flow rate rises to a certain level, a water-phase channel appears in the upper-layer oil phase. At the flow rate up to 4000, the two phases mutually penetrate so the oil-water interface gradually disappears. At the flow rate up to 8000, the oil-water interface completely mixes, so the effect of the interface on the bubble velocity is weakened. The entrainment height of bubbles on the lower liquid layer increases gradually with increasing gas flow rate. The interfacial actions of gas bubbles appear as a single-bubble action area and a double-bubble action area. The critical gas flow rate between these two areas is about 140 mL/min.\u003c/p\u003e\n\u003cp\u003e(2) Bubble size and shape change with airflow velocity in both humid and non-humid conditions. At the gas flow rate \u003cem\u003eQ\u003c/em\u003e\u0026thinsp;\u0026le;\u0026thinsp;1000 mL/min, the maximum bubble diameter under wet conditions is larger than that under non-wet conditions, but at \u003cem\u003eQ\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;1000 mL/min, the bubble diameter under non-wet conditions increases. Bubble coalescence is not in the inter-hole distance of 8-fold hole diameter. Therefore, the bubble rising height in 8-fold hole diameter varies linearly with time. Whereas, the bubbles coalesce at different heights in the inter-hole distance of 2-fold and 4-fold hole diameter, so the bubble rising heights do not vary linearly with time. The impact on the liquid-liquid interface and the impact on the interface fluctuation all decrease with the rise of the inter-hole distance. With the use of a double-nozzle injection gas, a too-small inter-hole distance will promote the bubble coalescence and form larger-size bubbles. Appropriately controlling the inter-hole distance can enlarge the interfacial impact, improve the slag-metal mixing, and promote the mass transfer and chemical reactions between slag and metals, thereby modestly improving smelting efficiency.\u003c/p\u003e\n\u003cp\u003e(3) Under the same conditions, larger bubbles are formed under wet conditions. Experiments showed that under wet conditions, the bubble volume will increase, which more significantly impacts the liquid-liquid interface and intensifies the interface fluctuation. These changes facilitate the slag-metal mass transfer and chemical reactions, which will modestly improve production efficiency.\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eAcknowledgments\u003c/h2\u003e\n\u003cp\u003eThe authors are grateful for the financial supports from the National Key Research and Development Program of China (2022YFB3304901).\u003c/p\u003e\n\u003ch2\u003eFunding\u0026nbsp;\u003c/h2\u003e\n\u003cp\u003eNational Key Research and Development Program of China (2022YFB3304901).\u003c/p\u003e\n\u003ch2\u003eConflicts of Interest\u003c/h2\u003e\n\u003cp\u003eThe authors declare that they have no conflict of interest.\u003c/p\u003e\n\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\n\u003cp\u003eWang SN and Wang J wrote the main manuscript. Wang W prepared figures 1-5. Cai XY prepared figures 6-9. Zhao HL and Lv C supervised. All authors reviewed the manuscript.\u003c/p\u003e\n\u003ch2\u003eData Availability Statement (Required)\u003c/h2\u003e\n\u003cp\u003eData can be made available upon reasonable request.\u003c/p\u003e\n\u003ch2\u003eInformed consent\u003c/h2\u003e\n\u003cp\u003eN/A\u003c/p\u003e\n\u003ch2\u003eEthical approval\u003c/h2\u003e\n\u003cp\u003eN/A\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eCao, Y., Maci\u0026aacute;n-Juan, R.: Numerical study of the central breakup behaviors of a large bubble rising in quiescent liquid. Chem. Eng. Sci. \u003cb\u003e225\u003c/b\u003e, 115804 (2020)\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCelata, G.P.: Measurements of rising Velocity of a small Bubble in a Stagnant Fluid in one-and two-component systems. Exp. Thermal Fluid Sci. \u003cb\u003e31\u003c/b\u003e(6), 609\u0026ndash;623 (2007)\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eChoi, K., Park, H.: Interfacial phenomena of the interaction between a liquid-liquid interface and rising bubble. Exp. Fluids. \u003cb\u003e62\u003c/b\u003e(6), 126 (2021)\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDayal, P., Beskow, K., Bj\u0026ouml;rkvall, J., Sichen, D.: Study of slag/metal interface in ladle treatment. Ironmak. steelmaking. \u003cb\u003e33\u003c/b\u003e(6), 454\u0026ndash;464 (2006)\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eEllingsen, K., Risso, F.: On the rise of an ellipsoidal Bubble in Water: Oscillatory Paths and Liquid-induced Velocity. J. 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Sin. \u003cb\u003e59\u003c/b\u003e(11), 1523\u0026ndash;1532 (2022)\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"bottom blown, wetting, gas-liquid-liquid, multiphase flow, bubble","lastPublishedDoi":"10.21203/rs.3.rs-4447533/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4447533/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eA water model of a bottom-blown system has been established for investigating the bubble rising characteristic from one liquid phase to another, and also to probe the liquid-liquid interfacial movement with bubble crossing. Bubble shape and its influence on the interface are studied using wetting and non-wetting nozzles, respectively. Larger-size bubbles are formed from wetting nozzles which enhanced the liquid-liquid interface fluctuation. With the use of a double-nozzle injection gas, a too-small inter-hole distance will promote the bubble coalescence and form larger-size bubbles, and appropriately controlling the inter-hole distance can improve the slag-metal mixing and transfer.\u003c/p\u003e","manuscriptTitle":"Water model experiments on bubble motion and bubbly flows in a gas-liquid-liquid multiphase reactor","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-06-04 08:32:11","doi":"10.21203/rs.3.rs-4447533/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"08f9eea7-3e98-45ed-84a9-862ad76ed7c6","owner":[],"postedDate":"June 4th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2024-06-11T05:26:49+00:00","versionOfRecord":[],"versionCreatedAt":"2024-06-04 08:32:11","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-4447533","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4447533","identity":"rs-4447533","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}