Hu Junhui,president of Tianfu Association(Singapore)and recipient of the Public Service Medal(PBM),has been leading community efforts to help new Chinese immigrants integrate into Singaporean society.Originally from H...Hu Junhui,president of Tianfu Association(Singapore)and recipient of the Public Service Medal(PBM),has been leading community efforts to help new Chinese immigrants integrate into Singaporean society.Originally from Hebei Province in China,Hu arrived in Singapore in 1994 as one of the first technical professionals dispatched by China.Since then,he has built a life and career firmly rooted in Singapore.Over more than four years at China Construction(South Pacific)Development Co Pte Ltd,he rose through the ranks from project engineer to site manager and eventually project director.In 1999,he left the company to start his own business,setting up a construction firm with several partners.His focus shifted to real estate in 2007,when he co-founded JVA Venture Pte Ltd.展开更多
In multiphase pumps transporting gas-liquid two-phase flows,the high-speed rotation of the impeller induces complex deformations in bubble shapes within the flow domain,making the prediction of gasliquid two-phase dra...In multiphase pumps transporting gas-liquid two-phase flows,the high-speed rotation of the impeller induces complex deformations in bubble shapes within the flow domain,making the prediction of gasliquid two-phase drag forces highly challenging in numerical simulations.To achieve precise prediction of the drag forces on irregular bubbles within multiphase pumps,this study modifies the existing bubble drag force model and applies the revised model to the prediction of gas-liquid two-phase flow within multiphase pumps.The research findings indicate that the modified drag force model significantly enhances the accuracy of predicting flow characteristics within the pump,particularly under high gas volume fraction conditions.The simulation results for gas phase distribution and vorticity exhibit strong agreement with experimental data.The modified drag model better captures the accumulation of the gas phase at the suction side of the impeller outlet.It also accurately predicts the vortex characteristics induced by bubble backflow from the trailing edges of the diffuser.Additionally,the adjustment of the drag coefficient enhances the model’s ability to represent local flow field characteristics,thereby optimizing the performance simulation methods of multiphase pumps.Compared to traditional drag force models,the modified model reduces prediction errors in head and efficiency by 36.4%and 27.5%,respectively.These results provide important theoretical foundations and model support for improving the accuracy of gas-liquid two-phase flow simulations and optimizing the design of multiphase pumps under high gas volume fraction conditions.展开更多
文摘Hu Junhui,president of Tianfu Association(Singapore)and recipient of the Public Service Medal(PBM),has been leading community efforts to help new Chinese immigrants integrate into Singaporean society.Originally from Hebei Province in China,Hu arrived in Singapore in 1994 as one of the first technical professionals dispatched by China.Since then,he has built a life and career firmly rooted in Singapore.Over more than four years at China Construction(South Pacific)Development Co Pte Ltd,he rose through the ranks from project engineer to site manager and eventually project director.In 1999,he left the company to start his own business,setting up a construction firm with several partners.His focus shifted to real estate in 2007,when he co-founded JVA Venture Pte Ltd.
基金funded by Sichuan Natural Science Foundation Outstanding Youth Science Foundation(No.2024NSFJQ0012)Key project of Regional Innovation and Development Joint Fund of National Natural Science Foundation(No.U23A20669)Sichuan Science and Technology Program(2022ZDZX0041).
文摘In multiphase pumps transporting gas-liquid two-phase flows,the high-speed rotation of the impeller induces complex deformations in bubble shapes within the flow domain,making the prediction of gasliquid two-phase drag forces highly challenging in numerical simulations.To achieve precise prediction of the drag forces on irregular bubbles within multiphase pumps,this study modifies the existing bubble drag force model and applies the revised model to the prediction of gas-liquid two-phase flow within multiphase pumps.The research findings indicate that the modified drag force model significantly enhances the accuracy of predicting flow characteristics within the pump,particularly under high gas volume fraction conditions.The simulation results for gas phase distribution and vorticity exhibit strong agreement with experimental data.The modified drag model better captures the accumulation of the gas phase at the suction side of the impeller outlet.It also accurately predicts the vortex characteristics induced by bubble backflow from the trailing edges of the diffuser.Additionally,the adjustment of the drag coefficient enhances the model’s ability to represent local flow field characteristics,thereby optimizing the performance simulation methods of multiphase pumps.Compared to traditional drag force models,the modified model reduces prediction errors in head and efficiency by 36.4%and 27.5%,respectively.These results provide important theoretical foundations and model support for improving the accuracy of gas-liquid two-phase flow simulations and optimizing the design of multiphase pumps under high gas volume fraction conditions.
