• Title/Summary/Keyword: 프리스월 시스템

Search Result 4, Processing Time 0.021 seconds

System Performance Variation for Relative Location of Pre-swirl Nozzles and Receiver Holes in Radial On-Board Injection Type Pre-swirl System (반경방향 분사방식 프리스월 시스템의 프리스월 노즐과 리시버 홀의 상대적 위치에 따른 시스템 성능변화)

  • Lee, Jonggeon;Lee, Hyungyu;Cho, Geonhwan;Cho, Jinsoo
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.48 no.1
    • /
    • pp.43-53
    • /
    • 2020
  • The effect of the relative location between pre-swirl nozzle and receiver hole on the performance of radial on-board injection type pre-swirl system was analyzed. In this study, tendency of the change of discharge coefficient and temperature drop efficiency were analyzed for 20 design points through the combination of 5 pre-swirl nozzle location and 4 receiver hole location. Discharge coefficient of system tended to be similar to the pressure ratio of the pre-swirl nozzle. System performance variation occurred as the flow structure in the cavity was affected by the surface, and the influence of the stationary surface is greater than that of the rotating surface. Discharge coefficient of system changed -1.39% to 1.25% and temperature drop efficiency changed -5.41% to 2.94% refer to reference design point.

Off-design Characteristics for Ambient Air Temperature and Turbine Load of Gas Turbine Pre-swirl System (가스터빈 프리스월 시스템의 외기 온도와 터빈 부하 조건에 따른 탈설계점 특성 분석)

  • Park, Hyunwoo;Lee, Jungsoo;Cho, Geonhwan;Cho, Jinsoo
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.47 no.12
    • /
    • pp.881-889
    • /
    • 2019
  • The pre-swirl system is the device that minimizes energy loss of turbine cooling airflow from the stationary parts into rotating parts. In this paper, an off-design analysis was conducted for the ambient air temperature and turbine load conditions. The discharge coefficient was constant for ambient air temperature and turbine load. However, adiabatic effectiveness was increased. This is due to the volume flow rate. The volume flow rate was increased at higher ambient temperature and higher turbine load. It means that the volume of cooling air was increased and the cooling performance of the air was improved. Consequently, adiabatic effectiveness increased by 30.46% at 100% turbine load compared to 20% turbine load. And increased by 18.42% at 55℃ ambient air temperature compared to -20℃ ambient air temperature.

Rotordynamic Analysis of Labyrinth Seal with Swirl Brake (스월 브레이크가 장착된 래버린스 씰의 동특성 해석)

  • Lee, Jeongin;Suh, Junho
    • Tribology and Lubricants
    • /
    • v.38 no.2
    • /
    • pp.63-69
    • /
    • 2022
  • In this research, the rotordynamic characteristics of the labyrinth seal with and without swirl brake were predicted using the computational fluid dynamic (CFD) model. Based on previous studies, a simple swirl brake consisting of square vanes without stagger angle is designed and placed in front of the seal inlet. The rotating frame of reference is utilized to consider the whirling motion of the rotor in the steady-state analysis since the whirling motion is transient behavior in nature. CFD analysis was performed in the range of -1 to 1 pre-swirl ratio for a given seal and swirl brake design and operating conditions. The CFD analysis result shows that the swirl brake effectively reduces the pre-swirl since the circumferential fluid velocity of labyrinth seal with swirl brake was lower than that without swirl brake. The cross-coupled stiffness coefficient, which is greatly affected by the circumferential fluid velocity, increased with an increasing pre-swirl ratio in a seal without a swirl brake but showed a low value in a seal with a swirl brake. The change in the damping coefficient was relatively small. The effective damping coefficient of the labyrinth seal with swirl brake was generally constant and showed a higher value than the labyrinth seal without swirl brake.

Pre-swirl Nozzle Geometry Optimization to Increase Discharge Coefficient Using CFD Analysis (Pre-swirl system의 유량계수 향상을 위한 Pre-swirl nozzle의 형상 최적화 전산해석 연구)

  • Lee, Hyungyu;Lee, Jungsoo;Kim, Donghwa;Cho, Jinsoo
    • The KSFM Journal of Fluid Machinery
    • /
    • v.20 no.1
    • /
    • pp.21-28
    • /
    • 2017
  • Optimization process of pre-swirl nozzle geometry was conducted to improve the discharge coefficient of pre-swirl system by using CFD. The optimization of pre-swirl nozzle shape covered the converging angle and the location of the converging nozzle. Optimization process included Optimal Latin Hyper-cube Design method to get the experimental points and the Kriging method to create the response surface which gives candidate points. The process was finished when the difference between the predicted value and CFD value of candidate point was less than 0.1 %. This paper compared the Reference model, Initial model which is the first model of optimization and Optimized model to study flow characteristics. Finally, the discharge coefficient of Optimized model is improved about 17 % to the Reference model.