• Title/Summary/Keyword: compressor surge

Search Result 94, Processing Time 0.026 seconds

Investigation of Off-Design Performance of Vaned Diffusers in Centrifugal Compressors - Part I : A Channel-Wedge Diffuser - (원심압축기용 베인디퓨져의 탈설계점 성능연구 - 제1부 : 채널디퓨져 -)

  • Oh, JongSik;Hyun, YongIk
    • 유체기계공업학회:학술대회논문집
    • /
    • 2001.11a
    • /
    • pp.83-90
    • /
    • 2001
  • Experimental and numerical investigations of the off·design performance of a simple channel-wedge diffuser in a small centrifugal compressor are presented. Surge and choke conditions as well as design point are considered using somewhat limited range of experimental data and also supplementary 3D CFD results. Some critical meanline design parameters' behavior is investigated numerically, to render the basis for improved modelings in the meanline performance prediction.

  • PDF

Turbojet Engine Control of UAV using Artificial Neural Network PID (인공신경망 PID를 이용한 무인항공기 터보제트 엔진 제어)

  • Kim, Dae-Gi;Hong, Gyo-Young;Ahn, Dong-Man;Hong, Seung-Beom;Jie, Min-Seok
    • Journal of Advanced Navigation Technology
    • /
    • v.18 no.2
    • /
    • pp.107-113
    • /
    • 2014
  • In this paper, controller Propose to prevent compressor surge and improve the transient response of the fuel flow control system of turbojet engine. Turbojet engine controller is designed by applying Artificial Neural Network PID control algorithm and make an inference by applying Artificial Neural Network Error Back Propagation Algorithm. To prevent any surge or a flame out event during the engine acceleration or deceleration, the ANN PID controller effectively controls the fuel flow input of the control system. ANN PID results are used as the fuel flow control inputs to prevent compressor surge and flame-out for turbo-jet engine and the controller is designed to converge to the desired speed quickly and safely. Using MATLAB to perform computer simulations verified the performance of the proposed controller. Response characteristics pursuant to the gain were analyzed by simulation.

A Study on Compressor Map Generation of a Gas Turbine Engine Using Hybrid Intelligent Method (하이브리드 기법을 이용한 가스터빈 엔진의 압축기 성능선도 생성에 관한 연구)

  • Kong, Chang-Duk;Kho, Seong-Hee;Ki, Ja-Young
    • Journal of the Korean Society of Propulsion Engineers
    • /
    • v.10 no.4
    • /
    • pp.54-60
    • /
    • 2006
  • A method for generating the compressor map from some performance measuring data using the hybrid intelligent technique was newly proposed. In order to improve accuracy of the traditional scaling method, a method to generate the compressor map using the GAs(Genetic Algorithms) was previously proposed, but the method has a drawback that it can not find correctly surge and choke points of the compressor map. However, the proposed hybrid intelligent method can determine obviously those points as well as improve the accuracy of the compressor map through complementarily using the GAs and the scaling method.

DESIGNING EXPERIENCE OF AUTOMOTIVE TURBOCHARGER IMPELLER FOR FLANK MILLING (Flank Milling 공법적용을 위한 자동차용 터보차져 임펠러의 설계체험)

  • Bang, J.C.;Shuripa, V.A.
    • Journal of computational fluids engineering
    • /
    • v.18 no.4
    • /
    • pp.1-8
    • /
    • 2013
  • The performance of small-size impellers with ruled surfaces was investigated for flank milling over a wide speed range, using computational fluid dynamics analyses and gas bench tests. An impeller with a ruled surface was designed, manufactured, and tested to evaluate the effects of blade loading, the backsweep angle, and the relative velocity distribution on the compressor performance. The simulations and tests were completed using the same compressor cover with identical inlet and outlet channels to accurately compare the performance of the abovementioned impeller with a commercial impeller containing sculptured blades. Both impellers have the same number of blades, number of splitters, and shroud meridional profiles. The backsweep angles of the blades on the ruled impeller were selected to work with the same pinched diffuser as for a sculptured impeller. The inlet-to-exit relative velocity diffusion ratio and the blade loading were provided to maximize the flow rate and to minimize the surge flow rate. The design flow rate, rpm, were selected same for both impellers. Test results showed that for the compressor stage with a ruled impeller, the efficiency was increased by 0.32% with an extended surge margin without a reduction in the pressure ratio as compared to the impeller with the sculptured design. It was concluded that an increased relative velocity diffusion coupled with a large backsweep angle was an effective way to improve the compressor stage efficiency. Additionally, an appropriate blade loading distribution was important for achieving a wide operating range and higher efficiency.

Effects of Axial Flow Compressor Surge on the Performance of Turbofan Engine (터보팬 엔진의 축류압축기 서지가 엔진성능에 미치는 영향)

  • Oh, Chang-Yong;Koo, Ja-Ye
    • Journal of the Korean Society of Propulsion Engineers
    • /
    • v.13 no.3
    • /
    • pp.1-8
    • /
    • 2009
  • This thesis has analyzed the effect of the surge happening in flight on the engine performance, especially on the PW4000 turbofan engine. It is to be judged that the flight surge can occur more often at the time of takeoff than it does en route due to the fact that the engine parameters are prone to fluctuate. EPR is judged to be the most highly sensitive parameter responding when surge occurs. Both Engine rpm and Wf decrease almost simultaneously just like an EPR. During the take-off rolling, N1 vibration is more sensitive than the N2 vibration. Consequently, the surge can be detected by EGT increase, while the other parameters (EPR, rpm, Wf, etc) decrease.

Study of Greitzer's B-Parameter Model Using ANOVA & Taguchi Method

  • Ng E. Y-K;Liu N.;Tan S. Y.
    • 한국전산유체공학회:학술대회논문집
    • /
    • 2003.10a
    • /
    • pp.197-199
    • /
    • 2003
  • In this work, the Greitzer's B-parameter model is applied for analyzing the stall and surge characteristics. The four parameters in the model are highlighted in order to establish the influence of each parameter on the system. First of all, the governing equations of stall and surge behavior are solved numerically using fourth-order Runge-Kutta method. The Taguchi method is then used to analyze the results generated to obtain the extent of effects of the parameters on the system by varying the parameters in a series of combinations. Finally, a thorough analysis is carried out on the results generated from the Taguchi method and the graphs.

  • PDF

Compressor BPF noise reduction for an automotive turbocharger (차량용 터보차져의 컴프레서 BPF 소음 저감)

  • Park, Ho-Il;Eom, Sang-Bong;Seo, Ju-Bong;Lee, Seung-Hyun
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2012.04a
    • /
    • pp.851-856
    • /
    • 2012
  • Automotive turbochargers have become common in gasoline engines as well as diesel engines. They are excellent devices to effectively increase fuel efficiency and power of the engines, but they unfortunately cause several noise problems. The noises are classified into mechanical noises induced from movement of a rotating shaft and aerodynamic noises by air flow in turbochargers. The mechanical noises are whine and howling noises, and the aerodynamic noises are BPF (blade-passing frequency), pulsation, surge, some special frequency noises. These noises are bothering passengers because their levels are higher or their frequencies are clearly separated from engine or vehicle noises. The noise investigated in this paper is a BPF noise induced by compressor wheels, whose frequency is the multiplication of the number of compressor wheel blades and its rotational speed. The noise is strongly dependent upon the geometry of wheels and the number of blades. This study tried to apply a groove close to the inlet side of compressor wheels in order to reduce the BPF noise. The groove has successfully reduced the noise of narrow band frequency of a turbocharger. It shows that the groove could reduce the wide band frequency noise, the compressor BPF noise with a best shape of the groove.

  • PDF

Flow Instability Assessment Occurring in Low Flow Rate Region According to the Change of a Centrifugal Compressor Impeller Shape (원심압축기 임펠러의 형상 변화에 따른 저유량 영역에서 발생하는 불안정 유동 평가)

  • Jo, Seong Hwi;Kim, Hong Jip;Lee, Myong Hee
    • The KSFM Journal of Fluid Machinery
    • /
    • v.19 no.2
    • /
    • pp.21-26
    • /
    • 2016
  • The objective of present study is to assess the performance of the first stage compressor in a total 3-stage 5000 HP-level turbo compressor. CFD commercial code, CFX has been used to predict three-dimensional flow characteristics inside of the impeller. Shear Stress Transport (SST) model has been used to simulate turbulent flows through Reynolds-averaged Navier-Stokes (RANS) equations. Grid dependency has been also checked to get optimal grid distribution. Numerical results have been compared with the experimental test results to elucidate performance characteristics of the present compressor. In addition, flow characteristics of the impeller only have been studied for various blade configurations. Angular offset in leading edge of the blade has been selected for the optimal blade design. Performance characteristics in region of low mass flow rate and high pressure ratio between the impeller entrance and exit have been investigated for the selection of optimal blade design. Also, flow instability such as stall phenomena has been studied and anti-stall characteristics have been checked for various blade configurations in the operational window.

Geometrical Effects of an Active Casing Treatment on Aerodynamic Performance of a Centrifugal Compressor (능동형 케이싱 트리트먼트의 형상 변화가 원심압축기의 공력성능에 미치는 영향)

  • Ma, Sang-Bum;Kim, Kwang-Yong
    • The KSFM Journal of Fluid Machinery
    • /
    • v.19 no.4
    • /
    • pp.5-12
    • /
    • 2016
  • In this study, a parametric study on a cavity as casing treatment of a centrifugal compressor has been conducted using three-dimensional Reynolds-averaged Navier-Stokes equations with shear stress transport turbulence model. Two kinds of cavity were applied at choke and surge conditions, respectively, in this work. Inlet and outlet port widths, angle of outlet port, and length of cavity were chosen as the geometric parameters and investigated to find their effects on the aerodynamic performances such as adiabatic efficiency at design mass flow rate and stall margin of the centrifugal compressor. It was found that the aerodynamic performances of the centrifugal compressor were affected considerably by the four geometric parameters. The adiabatic efficiency was hardly changed by the geometric parameters, excepts for the angle of outlet port. With an increase in the angle of outlet port, the adiabatic efficiency and the stall margin decreased. The stall margin was more sensitive to the outlet port width than to the other geometric parameters. And, with a decrease in the outlet port width, the stall margin increased by 2% compared to that of the reference.

Development of Performance Analysis Program for an Axial Compressor with Meanline Analysis (평균반경해석법을 이용한 축류압축기 성능해석 프로그램 개발)

  • Park, Jun-Young;Park, Moo-Ryong;Choi, Bum-Suk;Song, Je-Wook
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.33 no.2
    • /
    • pp.141-148
    • /
    • 2009
  • Axial-flow compressor is one of the most important parts of gas turbine units with axial turbine and combustor. Therefore, precise prediction of performance is very important for development of new compressor or modification of existing one. Meanline analysis is a simple, fast and powerful method for performance prediction of axial-flow compressors with different geometries. So, Meanline analysis is frequently used in preliminary design stage and performance analysis for given geometry data. Much correlations for meanline analysis have been developed theoretically and experimentally for estimating various types of losses and flow deviation angle for long time. In present study, meanline analysis program was developed to estimate compressor losses, incidence angles, deviation angles, stall and surge conditions with many correlations. Performance prediction of one stage axial compressors is conducted with this meanline analysis program. The comparison between experimental and numerical results show a good agreement. This meanline analysis program can be used for various types of single stage axial-flow compressors with different geometries, as well as multistage axial-flow compressors.