Two turbine rotors with outer rim and without outer rim were designed to analyze the influence of outer rim of rotors on the performance of a turbodrill. Two 3D models of the turbine rotor with different structures we...Two turbine rotors with outer rim and without outer rim were designed to analyze the influence of outer rim of rotors on the performance of a turbodrill. Two 3D models of the turbine rotor with different structures were established by SolidWorks software. The numerical simulation analysis of the turbine with different rotor structures was carried out based on software of fluent and then the performance of them at different rotating speeds was obtained. The results show that the torque,pressure drop and hydraulic efficiency of the turbine rotor with outer rim are greater than that of the turbine rotor without outer rim. By comparing the turbine rotor with outer rim and without outer rim,its torque increases 20. 1%,pressure drop increases 8.7% and hydraulic efficiency increases 10.4% at the maximum efficiency point. The related research is of guiding significance to further optimization of turbine rotor structure.展开更多
Back grinding of wafer with outer rim(BGWOR)is a new method for carrier-less thinning of silicon wafers.At present,the effects of process parameters on the grinding force remain debatable.Therefore,a BGWOR normal grin...Back grinding of wafer with outer rim(BGWOR)is a new method for carrier-less thinning of silicon wafers.At present,the effects of process parameters on the grinding force remain debatable.Therefore,a BGWOR normal grinding force model based on grain depth-of-cut was established,and the relationship between grinding parameters(wheel infeed rate,wheel rotational speed,and chuck rotational speed)and normal grinding force was discussed.Further,a series of experiments were performed to verify the BGWOR normal grinding force model.This study proves that the BGWOR normal grinding force is related to the rotational direction of the wheel and chuck,and the effect of grinding mark density on the BGWOR normal grinding force cannot be ignored.Moreover,this study provides methods for reducing the grinding force and optimizing the back thinning process of the silicon wafer.展开更多
基金National Natural Science Foundation of the Country Project(51704034)Major National Special topics(2016ZX05038-002-LH001)Zhonghai Petroleum(China)Co.Ltd.Zhanjiang Branch Project(CCL2017ZJFN2272)
文摘Two turbine rotors with outer rim and without outer rim were designed to analyze the influence of outer rim of rotors on the performance of a turbodrill. Two 3D models of the turbine rotor with different structures were established by SolidWorks software. The numerical simulation analysis of the turbine with different rotor structures was carried out based on software of fluent and then the performance of them at different rotating speeds was obtained. The results show that the torque,pressure drop and hydraulic efficiency of the turbine rotor with outer rim are greater than that of the turbine rotor without outer rim. By comparing the turbine rotor with outer rim and without outer rim,its torque increases 20. 1%,pressure drop increases 8.7% and hydraulic efficiency increases 10.4% at the maximum efficiency point. The related research is of guiding significance to further optimization of turbine rotor structure.
基金support from the National Key Research and Development Program of China(Grant No.2016YFB1102205)the National Natural Science Foundation of China(Grant No.51775084).
文摘Back grinding of wafer with outer rim(BGWOR)is a new method for carrier-less thinning of silicon wafers.At present,the effects of process parameters on the grinding force remain debatable.Therefore,a BGWOR normal grinding force model based on grain depth-of-cut was established,and the relationship between grinding parameters(wheel infeed rate,wheel rotational speed,and chuck rotational speed)and normal grinding force was discussed.Further,a series of experiments were performed to verify the BGWOR normal grinding force model.This study proves that the BGWOR normal grinding force is related to the rotational direction of the wheel and chuck,and the effect of grinding mark density on the BGWOR normal grinding force cannot be ignored.Moreover,this study provides methods for reducing the grinding force and optimizing the back thinning process of the silicon wafer.
