Critical Speed Analysis of a 75 Ton Class Liquid Rocket Engine Turbopump due to Load Characteristics

75톤급 액체로켓엔진 터보펌프의 하중 특성에 따른 임계속도 해석

  • 전성민 (한국항공우주연구원 터보펌프팀) ;
  • 곽현덕 (한국항공우주연구원 터보펌프팀) ;
  • 홍순삼 (한국항공우주연구원 터보펌프팀) ;
  • 김진한 (한국항공우주연구원 터보펌프팀)
  • Published : 2011.11.24


Critical speed of high thrust liquid rocket engine turbopump is obtained through a rotordynamic analysis and a unloaded turbopump test is peformed for validation of the numerical model. The first critical speed predicted by the numerical analysis is correlated well with the test result for the bearing unloaded rotor condition only considering mass unbalance load. Using the previous rotordynamic model, critical speed variation is estimated as a function of varied bearing stiffness due to pump and turbine radial loads with relative angle difference. From the numerical analysis, it is found that the relative angle difference of pump and turbine radial loads greatly affects the critical speed. However, additional axial load reduces the effect derived from the relative angle difference of radial loads.