• Title, Summary, Keyword: Design Flow

Search Result 7,890, Processing Time 0.055 seconds

Prediction of flow field in an axial compressor with a non-uniform tip clearance at the design and off-design conditions (설계점 및 탈설계점에서 비균일 익단 간극을 가지는 축류 압축기의 유동장 예측)

  • Kang, Young-Seok;Park, Tae-Choon;Kang, Shin-Hyoung
    • The KSFM Journal of Fluid Machinery
    • /
    • v.11 no.6
    • /
    • pp.46-53
    • /
    • 2008
  • Flow structures in an axial compressor with a non-uniform tip clearance were predicted by solving a simple prediction method. For more reliable prediction at the off-design condition, off-design flow characteristics such as loss and flow blockage were incorporated in the model. The predicted results showed that flow field near the design condition is largely dependent on the local tip clearance effect. However overall flow field characteristics are totally reversed at off-design condition, especially at the high flow coefficient. The tip clearance effect decreases, while the local loss and flow blockage make a complicated effect on the compressor flow field. The resultant fluid induced Alford's force has a negative value near the design condition and it reverses its sign as the flow coefficient increases and shows a very steep increase as the flow coefficient increases.

A Aerodynamic Design of Mixed Flow Turbine of the Marine Turbocharger (박용 터보챠저 사류 터빈의 공력설계)

  • Kim, Hong-Won;Oh, Kook-Taek;Ghal, Sang-Hak;Ha, Ji-Soo
    • Proceedings of the KSME Conference
    • /
    • /
    • pp.670-675
    • /
    • 2001
  • This paper describes aerodynamic preliminary design performance prediction and flow analysis for turbine of the marine middle engine turbocharger. The performance characteristics of turbocharger turbine are investigated at various operating conditions using mass flow rate and computational flow analysis for rotor and nozzle at design point are performed. Preliminary design results are performed by applying mean line and radial equilibrium theory. Performance prediction and flow analysis results show good agreement with experiments. From 3 dimensional flow analysis result, efficiency is 0.6% greater than design point. Therefore, this design approach is useful for preliminary design, and helps to increase the design capability for optimized rotor blade.

  • PDF

Optimum Design of a Cross Flow Fan (횡류팬의 최적설계방안)

  • Kim D. H.;Park H. K.
    • 한국전산유체공학회:학술대회논문집
    • /
    • /
    • pp.176-181
    • /
    • 2003
  • The cross-flow fans are widely used in various applications, due to their large capacity of mass flow and the size compactness. The flow fields of the cross-flow fan is, however, complex and it has many design parameters. Thus the general design guide has not sufficiently established yet, and the design strategies of cross-flow fans have been based on experiments. In the present study, the cross-flow fan performance and its two-dimensional flow characteristics are numerically analyzed by using the STAR-CD. The simulation is done by varying the several design parameters such as impeller blade shapes, the gap between the stabilizer and impeller. The computational results are compared with the experimental data at the fan outlet region. Finally some helpful guides for the optimum design of the cross-flow fan are proposed.

  • PDF

A Study on the Design of Liquid Flow Control Valves for the Plants and Ships (플랜트 및 선박의 액체용 유량제어밸브 설계에 관한 연구(I))

  • 최순호;박천태
    • Journal of the Korean Society of Marine Engineering
    • /
    • v.19 no.1
    • /
    • pp.28-35
    • /
    • 1995
  • The fluid flow for a energy transfer is essential for the design and operation of power plants, petrochemical plants and ships including a process. When the operating conditions of a plant are changed or any transitional event occured, the flow controls of a fluid must be performed to follow the new operating state or mitigate the results of a event. Generally these flow controls to accommodate the new operating state of a plant are made by the use of various valves. The refore the design of valves and the related techniques are very important to the system and component designs. However the system and component design are not familiar with the practical theory of the valve since the derivative procedures of the flow equations in a valve are difficult and it is not easy to found the theoretical foundamentals and informations about the design of a valve from the present references. In this study the flow equations applicable to a valve for liquid are theoretically derived in detail. And the definition of valve reynolds number and its boundary values between the tubulent and laminar flow is described compared with the values of a circular pipe flow.

  • PDF

Optimum Design of a Cross Flow Fan (횡류팬의 최적설계방안)

  • Kim Dong-Hoon;Park Hyung-Koo
    • Journal of computational fluids engineering
    • /
    • v.8 no.4
    • /
    • pp.50-57
    • /
    • 2003
  • Cross-flow fans are widely used in various applications, due to their large capacity of mass flow and size compactness. The flow field of the cross-flow fan is, however, complex and has many design parameters. Thus, the general design guide has not been sufficiently established yet and the design strategies of cross-flow fans have been mostly based on experiments. In the present study, the performance and their two-dimensional flow characteristics are numerically analyzed by using the STAR-CD(commercial computational fluid dynamics code). The simulation is done by varying the several design parameters such as the impeller blade shapes and the gap between the stabilizer and impeller. The computational results are compared with the experimental data at the fan outlet region. Finally, some helpful guides for the optimum design of cross-flow fans are proposed.

Optimum Design of a Cross Flow Fan

  • Kim Dong-Hoon;Park Hyung-Koo
    • 한국전산유체공학회:학술대회논문집
    • /
    • /
    • pp.260-262
    • /
    • 2003
  • Cross-flow fans are widely used in various applications, due to their large capacity of mass flow and size compactness. The flow field of the cross-flow fan is, however, complex and has many design parameters. Thus, the general design guide has not been sufficiently established yet and the design strategies of cross-flow fans have been based on experiments. In the present study, the performance and their two-dimensional flow characteristics are numerically analyzed by using the STAR-CD(commercial computational fluid dynamics code). The simulation is done by varying the several design parameters such as the impeller blade shapes and the gap between the stabilizer and impeller. The computational results are compared with the experimental data at the fan outlet region. Finally some helpful guides for the optimum design of cross-flow fans are proposed.

  • PDF

Design and Experimental Studies of Radial-Outflow Type Diagonal Flow Fan

  • Kinoue, Yoichi;Shiomi, Norimasa;Setoguchi, Toshiaki
    • International Journal of Fluid Machinery and Systems
    • /
    • v.6 no.1
    • /
    • pp.18-24
    • /
    • 2013
  • In order to apply the design method of diagonal flow fan based on axial flow design to the design of radial-outflow type diagonal flow fan which has lower specific speed of 600-700 [$min^{-1}$, $m^3/min$, m], radial-outflow type diagonal flow fan which specific speed was 670 [$min^{-1}$, $m^3/min$, m] was designed by a quasi three-dimensional design method. Experimental investigations were conducted by fan characteristics test, flow surveys by a five-hole probe and a hot wire probe. Fan characteristics test agreed well with the design values. In the flow survey at rotor outlet, the characteristic region was observed. Two flow phenomena are considered as the cause of the characteristic region, one is tip leakage vortex near rotor tip and another is pressure surface separation on the rotor blade.

A Numerical Study on the Design of a Central Flow Distributor Device Stabilizing Flow Uniformity in a vehicular fuel cell stack (차량용 연료전지 스택의 안정적 반응 가스 공급을 위한 중앙 유동 분배기 형상 설계에 관한 수치적 연구)

  • Jung, Hye-Mi;Um, Suk-Kee;Jeong, Hui-Seok;Lee, Seong-Ho;Seo, Jeong-Do;Son, Yeong-Jin
    • 한국신재생에너지학회:학술대회논문집
    • /
    • /
    • pp.554-557
    • /
    • 2008
  • In this study, two types of central flow distributor designs are presented and compared to obtain the optimal compact design which has the least flow resistance and the uniform flow distribution in a vehicular fuel cell stack. For effective and reliable prediction on the thermo-flow characteristics of the reactants flow over the entire fuel cell stack domain, open channel flow in the bipolar plates of the power generating cells were simulated by applying a simplified flow resistance model with an empirical porous concept. A number of case studies were performed to figure out an optimal configuration of a central flow distributor device in terms of the time-dependent thermo-flow behavior and load-dependent flow distribution. The results showed that the stable and load-independent thermo-flow uniformity is very design specific, which is closely associated with the design of central manifolding devices in order to achieve the enhanced volumetric power density and the reliable long-lasting operating of fuel cells.

  • PDF

Experimental Investigation on Separated Flows of Axial Flow Stator and Diagonal Flow Rotor

  • Kinoue, Yoichi;Shiomi, Norimasa;Setoguchi, Toshiaki;Jin, Yingzi
    • International Journal of Fluid Machinery and Systems
    • /
    • v.2 no.3
    • /
    • pp.223-231
    • /
    • 2009
  • Experimental investigations were conducted for the internal flows of the axial flow stator and diagonal flow rotor. Corner separation near the hub surface and the suction surface of stator blade are mainly focused on. For the design flow rate, the values of the axial velocity and the total pressure at stator outlet decrease between near the suction surface and near the hub surface by the influence of corner wall. For the flow rate of 80-90% of the design flow rate, the corner separation of the stator between the suction surface and the hub surface is observed, which becomes widely spread for 80% of the design flow rate. At rotor outlet for 81% of the design flow rate, the low axial velocity region grows between near the suction surface of rotor and the casing surface because of the tip leakage flow of the rotor.

Experimental Study on the Design Parameter Effects on the Flow-rate and the Noise level in a Cross-flow Fan (실험에 의한 직교류홴의 유량 및 소음 분석)

  • Ahn, Cheol-O;Rew, Ho-Seon
    • The KSFM Journal of Fluid Machinery
    • /
    • v.1 no.1
    • /
    • pp.41-48
    • /
    • 1998
  • This study was carried out to investigate the effect of design parameters on the volume flow-rate and the noise level and to finally find the optimal design variables. Eighteen cross-flow fans were designed by the method of orthogonal array, and the flow-rate and the noise level were measured. These data were analyzed by the neural network system. The effects of eight design variables(scroll exit angle, scroll arc length et al.) on the fan performance and the noise level were valuated and discussed. This experiment shows that the design solutions suggested by neural network system may increase its volume flow-rate and reduce noise simultaneously.

  • PDF