Cavitation Flow Simulation and Experiment Research in Inducer

2021 ◽  
Author(s):  
Liang Zhou ◽  
Longxian Li ◽  
Kexin Li

The inducer is a kind of special axial pump, which is widely used in industry communities, such as aerospace delivery systems and medical equipment. Inducer hydraulic performance is impacted sensitively by flow field cavitation. The external characteristic parameters of the turbopump are closely related to the cavitation in the inducer. The generation and changes of the cavitation in the inducer are the root cause of the drop in the turbopump head. The authors first take a low-temperature liquid rocket engine inducer as the research object, bring the numerical calculation and the visual test method to show the law of the generation and change of cavitation in the inducer and its correspondence with the external characteristic parameters of the turbopump, which explain the quantitative correspondence between the cavitation mode of the inducer and the macroscopic external characteristic curves of wheel pumps from a microscopic perspective. The numerical calculation method of cavitation flow field is introduced and the visualization test method is implemented to a proposed platform. The experimental results show that the numerical calculation results are in good agreement with the visualization test results, which indicate that the actual numerical method is practical and feasible for the calculation of the cavitation flow field in inducers. Finally, the pressure fluctuation frequency characteristic is obtained through the experimental and calculation post-process.

2021 ◽  
Vol 2125 (1) ◽  
pp. 012006
Author(s):  
Nan Wu ◽  
Chengpo Mu ◽  
Yang He ◽  
Huan Liu ◽  
Taiye Liu

Abstract In order to study the infrared radiation (IR) characteristics of rocket engine plume in the mid infrared band, a calculation model for IR transfer of rocket engine plume was built. The flow field data are calculated by software FLUENT. Based on HITRAN database, the IR characteristic parameters are calculated after spectral line correction. The Line of Sight (LoS) is used to solve the radiation characteristics in the plume flow field, and the IR characteristics distribution of the plume in the mid infrared band is obtained, which agree well with the results from open literature. The method has the advantages of simple model, less parameters and fast calculation speed in this paper.


Author(s):  
Kaname Kawatsu ◽  
Naoki Tani ◽  
Nobuhiro Yamanishi

For an open cycle liquid rocket engine, such as the expander bleed cycle, the mass flow rate of turbine driving gas should be small, especially to improve rocket engine performance. However, work output must be high as possible. As a result, pressure ratio of the turbine becomes high, and Mach number at both nozzle exit and rotor inlet becomes supersonic. As a result, strong shock wave interaction can be generated between nozzle exit and rotor inlet, and this interaction affects the turbine aerodynamic performance. However, this rotor-stator interaction of supersonic turbine has not yet been clarified. Therefore, as the first step, it is important to clarify the structure of the flow field and to evaluate the accuracy of CFD method as practical engineering tool for liquid rocket engine design. In the present study, quasi 3-D RANS simulations were applied to the NACA supersonic turbine and the numerical results were compared with the experimental ones to evaluate numerical methodology. Turbulence models and rotor/stator interface modeling method were compared, and their impacts to the turbine aerodynamic performance estimation were evaluated. In addition to these points, the flow field between nozzle and rotor region and the turbine efficiency were investigated. The present results clarify some features of rotor-stator interaction. The shock wave, which is generated near the nozzle exit caused by encounter of nozzle exit flow, reflects at the neighbor nozzle wall and affects the rotor region. At the same time, the shock wave from the rotor leading edge impinges the nozzle cascade, and these shocks interact with each other. The present results showed that Mach number at nozzle outlet becomes different due to each turbulence and rotor/stator interface models. This difference of Mach number influences the shape of detached shock wave at the leading edge of rotor blade, and changes the entire rotor region flow field such as static pressure profile of rotor region. Thus, turbine efficiency may be influenced by these different features of flow field.


Author(s):  
Arpit Mishra ◽  
Parthasarathi Ghosh

To obtain high specific work output with small mass flow rate, high-pressure ratios across the turbines are required in liquid rocket engine turbopumps. An impulse-type supersonic turbine can achieve this. To prevent losses due to low blade aspect ratio and issues related to manufacturing and industrial problems, partial admission configuration is adopted. Partial entry in a turbine is achieved by adjusting the extent of the nozzle arc of admission, leading to a strong unsteady circumferential asymmetry of flow parameters in the rotor passage, and degradation in efficiency. The pressing need of aerodynamic design of supersonic partial admission turbines to improve their efficiency demands an investigation of the viscous fluid dynamic of the turbine flow field. This work reports the aerothermodynamic steady state CFD analysis to obtain the performance parameters of a three-dimensional partial admission turbine for LOX booster turbopump in a semicryogenic engine using ANSYS® CFX. The areas of steady loss have been identified through entropy generation contours, and the effects associated with aerodynamic loss structures like secondary flow, shock location, recirculation with additional pumping and mixing losses have been investigated for designed operating condition corresponding to 100% nominal thrust.


Author(s):  
Yu Daimon ◽  
Hideyo Negishi ◽  
Hiroumi Tani ◽  
Yoshiki Matsuura ◽  
Shigeyasu Iihara ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document