Study on leakage flow characteristics of radial inflow turbines at rotor tip clearance  

作　　者：DENG QingHua NIU JiuFang FENG ZhenPing 

机构地区：[1]Institute of Turbomachinery,Xi’an Jiaotong University,Xi’an 710049,China

出　　处：《Science China(Technological Sciences)》2008年第8期1125-1136,共12页中国科学（技术科学英文版）

基　　金：Supported by National High Technology Research and Development Program of China (Grant Nos. 2002AA503020, 2004AA503020);Doctoral Foundation of Xi’an Jiaotong University (Grant No. DFXJTU2005-02)

摘　　要：Tip clearance leakage flow in a radial inflow turbine rotor for microturbines under the stage environment is investigated using a three-dimensional viscous flow simulation. The results indicate that the scraping flow caused by relative motion between casing and rotor tip, and the pressure difference between pressure side and suction side at rotor tip, play important roles in tip clearance leakage flow. The more the rotor tip speed increases and tip clearance height decreases, the more the scraping effect acts. Though the leakage velocity of tip clearance at midsection and exducer regions changes less when the rotor rotational speed is changing, the distance between passage vortex and rotor suction side varies in evidence. Main leakage flow rate of tip clearance takes place at region of exducer tip and some seal configurations will be quite effective for cutting leakage flow if these configurations are arranged over midsection and exducer of the radial inflow rotor.Tip clearance leakage flow in a radial inflow turbine rotor for microturbines under the stage environment is investigated using a three-dimensional viscous flow simulation. The results indicate that the scraping flow caused by relative motion between casing and rotor tip, and the pressure difference between pressure side and suction side at rotor tip, play important roles in tip clearance leakage flow. The more the rotor tip speed increases and tip clearance height decreases, the more the scraping effect acts. Though the leakage velocity of tip clearance at midsection and exducer regions changes less when the rotor rotational speed is changing, the distance between passage vortex and rotor suction side varies in evidence. Main leakage flow rate of tip clearance takes place at region of exducer tip and some seal configurations will be quite effective for cutting leakage flow if these configurations are arranged over midsection and exducer of the radial inflow rotor.

关 键 词：MICROTURBINE RADIAL INFLOW turbine ROTOR TIP CLEARANCE 

分 类 号：V235.111[航空宇航科学与技术—航空宇航推进理论与工程]