The tip leakage flow has an important influence on the performance of transonic com- pressor. Blade tip winglet has been proved to be an effective method to control the tip leakage flow in compressor, while the physic...The tip leakage flow has an important influence on the performance of transonic com- pressor. Blade tip winglet has been proved to be an effective method to control the tip leakage flow in compressor, while the physical mechanisms of blade tip winglet have been poorly understood. A numerical study for a highly loaded transonic compressor rotor has been conducted to understand the effect of varying the location of blade tip wing]et on the performance of the rotor. Two kinds of tip winglet were designed and investigated. The effects of blade tip winglet on the compressor over- all performance, stability and tip flow structure were presented and discussed, It is found that the interaction of the tip winglet with the flow in the tip region is different when the winglet is located at suction-side or pressure-side of the blade tip. Results indicate that the suction-side winglet （SW） is ineffective to improve the performance of compressor rotor. In addition, a significant stall range extension equivalent to 33.74% with a very small penalty in efficiency can be obtained by the pressure-side winglet （PW）. An attempt has been made to explain the fundamental mechanisms of blade tip winglet in detail.展开更多
针对某前驱车出现的clunk问题,在详细了解该车型传动系结构的基础上,分析该车型tip in clunk产生机理和传动系动态间隙理论计算方法,并用试验的方法获取传动系间隙值。详细介绍标定控制策略和优化方法,并尝试从标定和传递路径上解决该问...针对某前驱车出现的clunk问题,在详细了解该车型传动系结构的基础上,分析该车型tip in clunk产生机理和传动系动态间隙理论计算方法,并用试验的方法获取传动系间隙值。详细介绍标定控制策略和优化方法,并尝试从标定和传递路径上解决该问题,但实际效果不理想。进一步研究发现,采取将移动节球环直径增大0.1 mm和把移动节油脂更换为CX-SP1的油脂的方法,并用减小间隙和减小摩擦的工程样件进行整车验证,结果表明转向节的冲击振动消失,clunk优化明显,客户驾评表示可以接受。展开更多
The method of complex function and the method of Green's function are used to investigate the problem of SH-wave scattering by radial cracks of any limited length along the radius originating at the boundary of an...The method of complex function and the method of Green's function are used to investigate the problem of SH-wave scattering by radial cracks of any limited length along the radius originating at the boundary of an elliptical hole, and the solution of dynamic stress intensity factor at the crack tip was given. A Green's function was constructed for the problem, which is a basic solution of displacement field for an elastic half space containing a half elliptical gap impacted by anti-plane harmonic linear source force at any point of its horizontal boundary. With division of a crack technique, a series of integral equations can be established on the conditions of continuity and the solution of dynamic stress intensity factor can be obtained. The influence of an elliptical hole on the dynamic stress intensity factor at the crack tip was discussed.展开更多
基金co-supported by the National Natural Science Foundation of China(Nos.51436002,51406021)the Scientific Research Fund of Education Department of Liaoning Province(No.L2014197)+1 种基金the Program for Liaoning Innovative Research Team in University(No.LT2015004)the Fundamental Research Funds for the Central Universities(Nos.3132016014,3132014319)
文摘The tip leakage flow has an important influence on the performance of transonic com- pressor. Blade tip winglet has been proved to be an effective method to control the tip leakage flow in compressor, while the physical mechanisms of blade tip winglet have been poorly understood. A numerical study for a highly loaded transonic compressor rotor has been conducted to understand the effect of varying the location of blade tip wing]et on the performance of the rotor. Two kinds of tip winglet were designed and investigated. The effects of blade tip winglet on the compressor over- all performance, stability and tip flow structure were presented and discussed, It is found that the interaction of the tip winglet with the flow in the tip region is different when the winglet is located at suction-side or pressure-side of the blade tip. Results indicate that the suction-side winglet （SW） is ineffective to improve the performance of compressor rotor. In addition, a significant stall range extension equivalent to 33.74% with a very small penalty in efficiency can be obtained by the pressure-side winglet （PW）. An attempt has been made to explain the fundamental mechanisms of blade tip winglet in detail.
文摘针对某前驱车出现的clunk问题,在详细了解该车型传动系结构的基础上,分析该车型tip in clunk产生机理和传动系动态间隙理论计算方法,并用试验的方法获取传动系间隙值。详细介绍标定控制策略和优化方法,并尝试从标定和传递路径上解决该问题,但实际效果不理想。进一步研究发现,采取将移动节球环直径增大0.1 mm和把移动节油脂更换为CX-SP1的油脂的方法,并用减小间隙和减小摩擦的工程样件进行整车验证,结果表明转向节的冲击振动消失,clunk优化明显,客户驾评表示可以接受。
文摘The method of complex function and the method of Green's function are used to investigate the problem of SH-wave scattering by radial cracks of any limited length along the radius originating at the boundary of an elliptical hole, and the solution of dynamic stress intensity factor at the crack tip was given. A Green's function was constructed for the problem, which is a basic solution of displacement field for an elastic half space containing a half elliptical gap impacted by anti-plane harmonic linear source force at any point of its horizontal boundary. With division of a crack technique, a series of integral equations can be established on the conditions of continuity and the solution of dynamic stress intensity factor can be obtained. The influence of an elliptical hole on the dynamic stress intensity factor at the crack tip was discussed.
