Haider Ali¹, Kyung Won Kim¹, Jae Sik Kim², Jong Yun Choi³, Cheol Woo Park^1*

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¹ School of Mechanical Engineering, Kyungpook National University, Daegu, Korea.
² Podomaul Co., Ltd., 1190 Kumchang-Ro, Daechang-Myon, Yeongcheon-Si, Korea.
³ B.C.M. Co., Ltd., 81 Yeomsaekgongdancheon-Ro, Seo-Gu, Daegu, Korea.
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Abstract: The Euler-Euler numerical method was used to investigate the effects of contraction ratio on twophase flow mixing with mass transfer in the flow injection nozzle. The geometric shape of the nozzle was modified to improve carbonation efficiency. A gas inlet hole was created to increase the flow mixing of CO2 with water. A nozzle throat was also introduced to increase the gas dissolution by increasing flow rates. Various contraction ratios of nozzle throat, inlet gas and liquid velocities, and gas bubble sizes were employed to determine their effects on gas hold-up, gas concentration, and mass transfer coefficient. Results revealed that the flow injection nozzle with high contraction ratios improved carbonation because of high gas hold-up. Gas concentration was directly related to contraction ratio and gas flow velocities. Carbonation reduced when high liquid velocities and large gas bubbles were employed because of inefficient flow mixing. This study indicated that flow injection nozzle with large contraction ratios were suitable for carbonation because of their ability to increase gas hold-up, gas concentration, and mass transfer coefficient.

Keywords: Flow Injection Nozzle, Nozzle Throat, Contraction Ratio, Gas-Liquid Flow, Mass Transfer

Cite this paper: Ali, H. , Kim, K. , Kim, J. , Choi, J. and Park, C. (2016) Numerical Study on the Effects of Contraction Ratio in a Two-Phase Flow Injection Nozzle. Open Journal of Fluid Dynamics, 6, 1-10. doi: 10.4236/ojfd.2016.61001.

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