Investigation of Oil Droplet Breakup during Atomization of Emulsions: Comparison of Pressure Swirl and Twin-Fluid Atomizers
The goal of this study was to investigate oil droplet breakup in food emulsions during atomization with pressure swirl (PS), internal mixing (IM), and external mixing (EM) twin-fluid atomizers. By this, new knowledge is provided that facilitates the design of atomization processes, taking into accou...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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MDPI AG
2021-06-01
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| Series: | Fluids |
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| Online Access: | https://www.mdpi.com/2311-5521/6/6/219 |
| _version_ | 1827689978626310144 |
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| author | Martha L. Taboada Esteban Zapata Heike P. Karbstein Volker Gaukel |
| author_facet | Martha L. Taboada Esteban Zapata Heike P. Karbstein Volker Gaukel |
| author_sort | Martha L. Taboada |
| collection | DOAJ |
| description | The goal of this study was to investigate oil droplet breakup in food emulsions during atomization with pressure swirl (PS), internal mixing (IM), and external mixing (EM) twin-fluid atomizers. By this, new knowledge is provided that facilitates the design of atomization processes, taking into account atomization performance as well as product characteristics (oil droplet size). Atomization experiments were performed in pilot plant scale at liquid volume flow rates of 21.8, 28.0, and 33.3 L/h. Corresponding liquid pressures in the range of 50–200 bar and air-to-liquid ratios in the range of 0.03–0.5 were applied. Two approaches were followed: oil droplet breakup was initially compared for conditions by which the same spray droplet sizes were achieved at constant liquid throughput. For all volume flow rates, the strongest oil droplet breakup was obtained with the PS nozzle, followed by the IM and the EM twin-fluid atomizer. In a second approach, the concept of energy density <i>E<sub>V</sub></i> was used to characterize the sizes of resulting spray droplets and of the dispersed oil droplets in the spray. For all nozzles, Sauter mean diameters of spray and oil droplets showed a power-law dependency on <i>E<sub>V</sub></i>. PS nozzles achieved the smallest spray droplet sizes and the strongest oil droplet breakup for a constant <i>E<sub>V</sub></i>. In twin-fluid atomizers, the nozzle type (IM or EM) has a significant influence on the resulting oil droplet size, even when the resulting spray droplet size is independent of this nozzle type. Overall, it was shown that the proposed concept of <i>E<sub>V</sub></i> allows formulating process functions that simplify the design of atomization processes regarding both spray and oil droplet sizes. |
| first_indexed | 2024-03-10T10:30:02Z |
| format | Article |
| id | doaj.art-227647de858f4532b852108318c59ae0 |
| institution | Directory Open Access Journal |
| issn | 2311-5521 |
| language | English |
| last_indexed | 2024-03-10T10:30:02Z |
| publishDate | 2021-06-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Fluids |
| spelling | doaj.art-227647de858f4532b852108318c59ae02023-11-21T23:40:48ZengMDPI AGFluids2311-55212021-06-016621910.3390/fluids6060219Investigation of Oil Droplet Breakup during Atomization of Emulsions: Comparison of Pressure Swirl and Twin-Fluid AtomizersMartha L. Taboada0Esteban Zapata1Heike P. Karbstein2Volker Gaukel3Institute of Process Engineering in Life Sciences, Chair of Food Process Engineering, Karlsruhe Institute of Technology, Kaiserstraße 12, 76131 Karlsruhe, GermanyInstitute of Process Engineering in Life Sciences, Chair of Food Process Engineering, Karlsruhe Institute of Technology, Kaiserstraße 12, 76131 Karlsruhe, GermanyInstitute of Process Engineering in Life Sciences, Chair of Food Process Engineering, Karlsruhe Institute of Technology, Kaiserstraße 12, 76131 Karlsruhe, GermanyInstitute of Process Engineering in Life Sciences, Chair of Food Process Engineering, Karlsruhe Institute of Technology, Kaiserstraße 12, 76131 Karlsruhe, GermanyThe goal of this study was to investigate oil droplet breakup in food emulsions during atomization with pressure swirl (PS), internal mixing (IM), and external mixing (EM) twin-fluid atomizers. By this, new knowledge is provided that facilitates the design of atomization processes, taking into account atomization performance as well as product characteristics (oil droplet size). Atomization experiments were performed in pilot plant scale at liquid volume flow rates of 21.8, 28.0, and 33.3 L/h. Corresponding liquid pressures in the range of 50–200 bar and air-to-liquid ratios in the range of 0.03–0.5 were applied. Two approaches were followed: oil droplet breakup was initially compared for conditions by which the same spray droplet sizes were achieved at constant liquid throughput. For all volume flow rates, the strongest oil droplet breakup was obtained with the PS nozzle, followed by the IM and the EM twin-fluid atomizer. In a second approach, the concept of energy density <i>E<sub>V</sub></i> was used to characterize the sizes of resulting spray droplets and of the dispersed oil droplets in the spray. For all nozzles, Sauter mean diameters of spray and oil droplets showed a power-law dependency on <i>E<sub>V</sub></i>. PS nozzles achieved the smallest spray droplet sizes and the strongest oil droplet breakup for a constant <i>E<sub>V</sub></i>. In twin-fluid atomizers, the nozzle type (IM or EM) has a significant influence on the resulting oil droplet size, even when the resulting spray droplet size is independent of this nozzle type. Overall, it was shown that the proposed concept of <i>E<sub>V</sub></i> allows formulating process functions that simplify the design of atomization processes regarding both spray and oil droplet sizes.https://www.mdpi.com/2311-5521/6/6/219atomizationoil-in-water emulsionoil droplet breakuppressure swirl atomizertwin-fluid atomizerenergy density |
| spellingShingle | Martha L. Taboada Esteban Zapata Heike P. Karbstein Volker Gaukel Investigation of Oil Droplet Breakup during Atomization of Emulsions: Comparison of Pressure Swirl and Twin-Fluid Atomizers Fluids atomization oil-in-water emulsion oil droplet breakup pressure swirl atomizer twin-fluid atomizer energy density |
| title | Investigation of Oil Droplet Breakup during Atomization of Emulsions: Comparison of Pressure Swirl and Twin-Fluid Atomizers |
| title_full | Investigation of Oil Droplet Breakup during Atomization of Emulsions: Comparison of Pressure Swirl and Twin-Fluid Atomizers |
| title_fullStr | Investigation of Oil Droplet Breakup during Atomization of Emulsions: Comparison of Pressure Swirl and Twin-Fluid Atomizers |
| title_full_unstemmed | Investigation of Oil Droplet Breakup during Atomization of Emulsions: Comparison of Pressure Swirl and Twin-Fluid Atomizers |
| title_short | Investigation of Oil Droplet Breakup during Atomization of Emulsions: Comparison of Pressure Swirl and Twin-Fluid Atomizers |
| title_sort | investigation of oil droplet breakup during atomization of emulsions comparison of pressure swirl and twin fluid atomizers |
| topic | atomization oil-in-water emulsion oil droplet breakup pressure swirl atomizer twin-fluid atomizer energy density |
| url | https://www.mdpi.com/2311-5521/6/6/219 |
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