Experiments were conducted to study characteristics of flow when flow is fluctuating.The experimental results showed a phase difference between the flow rate and the pressure drop fluctuations.This phase difference be...Experiments were conducted to study characteristics of flow when flow is fluctuating.The experimental results showed a phase difference between the flow rate and the pressure drop fluctuations.This phase difference between the fluctuating flow rate and pressure drop was analyzed for laminar flow.Analysis showed that the phase difference changes with the period of the flow fluctuation, the pipe radius, the density and the dynamic viscosity of the liquid.Fluctuating pipe flow was then numerically simulated.Results of the numerical simulation were compared with theoretical values and experimental results.It was shown that, when the flow rate fluctuates with time as a sine wave, the pressure drop fluctuates with the same periodicity, and there is a phase difference between them.展开更多
Flow rate distribution is important in a multi channel system when the flow is heated non-uniformly.This paper describes a steady state approach for obtaining the flow distribution among various tubes of complex multi...Flow rate distribution is important in a multi channel system when the flow is heated non-uniformly.This paper describes a steady state approach for obtaining the flow distribution among various tubes of complex multi channel system. Based on the present approach,a program has been developed,which is directly applied in thermal hydraulic design and investigation of 600MW supercritical variable-pressure once through boiler.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No.50806014the Foundation of Bubble Physics and Natural Circulation Laboratory of China under Grant No.51482010105CB0101 and No.9140C7105020805
文摘Experiments were conducted to study characteristics of flow when flow is fluctuating.The experimental results showed a phase difference between the flow rate and the pressure drop fluctuations.This phase difference between the fluctuating flow rate and pressure drop was analyzed for laminar flow.Analysis showed that the phase difference changes with the period of the flow fluctuation, the pipe radius, the density and the dynamic viscosity of the liquid.Fluctuating pipe flow was then numerically simulated.Results of the numerical simulation were compared with theoretical values and experimental results.It was shown that, when the flow rate fluctuates with time as a sine wave, the pressure drop fluctuates with the same periodicity, and there is a phase difference between them.
文摘Flow rate distribution is important in a multi channel system when the flow is heated non-uniformly.This paper describes a steady state approach for obtaining the flow distribution among various tubes of complex multi channel system. Based on the present approach,a program has been developed,which is directly applied in thermal hydraulic design and investigation of 600MW supercritical variable-pressure once through boiler.
