An analytical and experimental study was conducted to investigate the effects of concurrent changes in curvature and cross-sectional areas on flow in a two-dimensioanl, S-shaped duct. A computer code based on the inverse method for the design of two-dimensional ducts was developed and has been supplemented by a boundary layer analysis code. Numerical experiments were performed by generating ducts of varying geometries and selecting the one providing an approximately optimal duct for a given offset-to-length ratio. The criteria for optimization were to achieve maximum pressure recovery and yet to avoid flow separation. After several numerical experiments, a 1:2 pressure ratio, S-shaped diffuser geometry was selected, and a physical model was built and tested. using a Laser-Doppler Velocimeter and a multiport, pressure-measuring Scanivalve system, static pressure, velocity, and turbulence measurements were obtained for flow in the model duct at three different Reynolds numbers. The experimental results closely match the theoretical predictions. This study provides results and conclusions which should be of interest to scientists and engineers involved with the fluid mechanics of internal flows and particularly with the flow in helicopter and fixed-wing aircraft engine inlet ducts.


    Access

    Access via TIB

    Check availability in my library


    Export, share and cite



    Title :

    Turbulent incompressible air flow through S-shaped ducts with cross-sectional area change


    Additional title:

    Turbulente inkompressible Luftstroemung durch S-foermige Leitungen mit Aenderung der Querschnittsflaeche


    Contributors:


    Publication date :

    1989


    Size :

    9 Seiten, 11 Bilder, 11 Quellen


    Type of media :

    Conference paper


    Type of material :

    Print


    Language :

    English




    Incompressible flow in contracting ducts

    Gibbings, J.C. | Online Contents | 1993



    Three-dimensional incompressible flow simulation in curved ducts

    HAMED, A. / SHIH, S. / ABDALLAH, S. | AIAA | 1989


    Flow through curved ducts of decreasing area

    KUMAR, K. / RANKIN, G. / SRIDHAR, K. | AIAA | 1987


    Three-dimensional viscous incompressible flow in curved polar ducts

    GHIA, U. / GHIA, K. / GOYAL, R. | AIAA | 1979