【摘 要】
：
Blade tip profile based on NACA airfoil is firstly introduced into the radial expander to suppress the tip leakage loss.A blade with optimal NACA tip profile is obtained by coupling orthogonal experim
【机 构】
：
Institute of Engineering Thermophysics,Chinese Academy of Sciences,Beijing,China
论文部分内容阅读
Blade tip profile based on NACA airfoil is firstly introduced into the radial expander to suppress the tip leakage loss.A blade with optimal NACA tip profile is obtained by coupling orthogonal experiment design and Computational Fluid Dynamic(CFD)model.The tip leakage flow loss reduction mechanism is also revealed.The results illustrate that the optimal NACA tip profile presents smaller leading edge inscribed circle radius,thinner trailing edge.Its maximum thickness location also close to the front edge.Influence of leading edge inscribed circle radius and maximum thickness location on radial expanders efficiency increases with the increase of tip clearance.The blade with optimal NACA tip profile even increases the radial expanders efficiency by 1.47%when tip clearance is 8%,and it also presents higher efficiency at different pressure ratio.The blade with optimal NACA tip profile reduces tip leakage flow velocity near the trialing edge region,weakens the mixing strength between leakage flow and mainstream,and therefore decreases flow loss.It also can improve the efficiency of radial expander,under variable operation condition of CAES system.
其他文献
Although much attention has been paid to the supercritical CO2(S-CO2)Brayton cycle,there are still few works on the analysis and design of S-CO2 cycle tailored to the needs of the shipboard propulsion
对某船用水泵机组进行振动测试,通过机组的特征频谱分析,找出其可能对应的影响因素.通过水泵机组模态测试出的参数结果分析,自身结构及安装基础不是引起该特征谱线的主要原因.再应用流场分析方法对水泵机组的水力模型进行有限元仿真分析,包括吸水室流道、叶轮流道和压水室流道,找出影响振动的流体激励因素.最后根据流场分析的结论,改进优化了水泵机组的叶轮水力模型,消除了水流速度线漩涡现象.成功地应用水力优化技术抑制
本文对碳纤维冷却风扇的技术特点进行了详细阐述.碳纤维冷却风扇采用设计、建模、优化三维一体的设计方法和先进的夹心结构模具工艺制造.经过试验验证和运用考核,碳纤维冷却风扇各项技术指标明显优于传统铸铝冷却风扇.采用碳纤维复合材料能够生产出外形高度契合理论设计的风扇叶型,有效改善机车冷却风扇的气动性能,减少轮轴负载,降低功率消耗和气动噪声.
The flow structure in the rotor tip region and stall mechanism for a mixed-flow compressor with various tip gaps are investigated in this paper.Steady simulations are carried out for tip clearances of
为了精确剔除GNSS（global navigation satellite system）坐标时间序列中的噪声，本文提出一种联合遗传算法（genetic algorithm， GA）和变分模态分解（variational mode decomposition， VMD）的降噪方法GA-VMD。该方法首先利用GA优化VMD参数，然后引入多尺度排列熵（multiscale permutation e
识别推力轴承轴向刚度对研究转子振动及轴承故障具有重要意义.首先建立推力轴承的力学模型,推导了推力轴承轴向刚度参数识别算法,并给出了相应的测量方法.然后,在半仿真离心压缩机试验台上,设计安装了具有轴向载荷加载功能的推力轴承试验装置,可利用电动液压泵和溢流阀实现静态和动态轴向载荷加载,分别采用传统载荷增量法和直接液压激励法的试验方法识别推力轴承的轴向刚度.最后,将试验结果与轴向刚度仿真值进行对比,发现
In turbomachinery design,rotor dynamics analysis is the most important part of the overall design process.Through the rotor dynamics analysis,the critical speed of the rotor can be analyzed,which can
This paper conducts a comprehensive study between single-camera Light Field Particle Image Velocimetry(LF-PIV)and multi-camera Tomographic Particle Image Velocimetry(Tomo-PIV).The dense ray tracing ba
High-speed high-pressure(HSHP)ratio compressor surge is a transient breakdown in compression accompanied by an abrupt momentary reversal of gas flow.It commonly exists in dynamic type turbo compressor
Since various foreign bodies can cause clogging and wear in the single-channel pump,considerable attentions have been focused on the numerical study of liquid-solid flows in the singlechannel pump.How