The article is an attempt to compile the results of CFD liquid flow simulation through pipeline section containing hydraulic elbow with the results of ultrasonic flow measurements. To carry out the measurements behind...The article is an attempt to compile the results of CFD liquid flow simulation through pipeline section containing hydraulic elbow with the results of ultrasonic flow measurements. To carry out the measurements behind the flow disturbing element(hydraulic elbow), an ultrasonic flowmeter with applied head set in accordance with the Z-type system was used. For comparative purposes, a flow simulation for 3 different turbulence models(k-epsilon, SST and SSG) was performed. It was found that with a proper ultrasonic flowmeter heads configurations, it is possible to measure the flow rate disturbed by the hydraulic elbow at any distance from the source of the disturbance. It has to use appropriate correction factor that can be determined by knowing the flow velocity profile equation. Based on comparison of CFD simulation results with experimental data, the accuracy/purposefulness of using individual turbulence models in the case of discussed hydraulic installation was evaluated.展开更多
This paper presents an improved thermal design methodology for wind power converters.It combines analysis and experimental thermal design tools,including heat transfer correlations,flow network modeling(FNM),computati...This paper presents an improved thermal design methodology for wind power converters.It combines analysis and experimental thermal design tools,including heat transfer correlations,flow network modeling(FNM),computational fluid dynamics(CFD),and experimental measurement techniques.Moreover,a systemic product development process is introduced and an effective combination between the product development process and the thermal design methodology is achieved.The draft CFD modeling at the initial design stage is done.Furthermore,it uses the detailed CFD modeling and experimental measurement techniques to provide a higher degree of accuracy at latter design stages.The key advantage of the improved methodology is its emphasis on the use of varied design tools,each of which is actively applied at its optimal point in the proposed product development process.Thus,during the earlier stages of the product development process,the thermal risk is systematically reduced,and longterm reliability of products is maintained in a higher degree.展开更多
文摘The article is an attempt to compile the results of CFD liquid flow simulation through pipeline section containing hydraulic elbow with the results of ultrasonic flow measurements. To carry out the measurements behind the flow disturbing element(hydraulic elbow), an ultrasonic flowmeter with applied head set in accordance with the Z-type system was used. For comparative purposes, a flow simulation for 3 different turbulence models(k-epsilon, SST and SSG) was performed. It was found that with a proper ultrasonic flowmeter heads configurations, it is possible to measure the flow rate disturbed by the hydraulic elbow at any distance from the source of the disturbance. It has to use appropriate correction factor that can be determined by knowing the flow velocity profile equation. Based on comparison of CFD simulation results with experimental data, the accuracy/purposefulness of using individual turbulence models in the case of discussed hydraulic installation was evaluated.
文摘This paper presents an improved thermal design methodology for wind power converters.It combines analysis and experimental thermal design tools,including heat transfer correlations,flow network modeling(FNM),computational fluid dynamics(CFD),and experimental measurement techniques.Moreover,a systemic product development process is introduced and an effective combination between the product development process and the thermal design methodology is achieved.The draft CFD modeling at the initial design stage is done.Furthermore,it uses the detailed CFD modeling and experimental measurement techniques to provide a higher degree of accuracy at latter design stages.The key advantage of the improved methodology is its emphasis on the use of varied design tools,each of which is actively applied at its optimal point in the proposed product development process.Thus,during the earlier stages of the product development process,the thermal risk is systematically reduced,and longterm reliability of products is maintained in a higher degree.
