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Paweł Wirkowski - One of the best experts on this subject based on the ideXlab platform.

  • modelling research of the characteristics of gasturbine axial compressor with changeable Flow Passage Geometry
    Journal of KONES, 2011
    Co-Authors: Paweł Wirkowski
    Abstract:

    In real exploitational conditions marine gasturbine engine works at different rotation speeds determined by the required parameters of ship’s movement. Conversion from one rotation speed to another is related to realization of unsteady energetic processes, determined by the gasodynamic mutual influence of compressor configurations. The values of working medium Flow thermodynamic parameters undergo significant changes in time. To work out the qualitative and quantitative estimation of these changes it is necessary to define the dynamic equations, describing working medium Flow through the gas Passage of engine. In the next step it is necessary to resolve the defined equations for disturbances of steady cooperation of compressor configurations. This paper concerns the application of mathematical modelling methods to analyzing gas-dynamic processes in marine gas turbines. The influence of Geometry changes in axial compressor Flow Passage on kinematical air Flow characteristics is presented. The elaborated mathematical model will make it possible to realize – in the future – simulative investigations of gas-dynamic processes taking place in a compressor fitted with controllable guide vanes. Individual parametric features of every engine in service are identified by using expensive experimental tests, which are conditioned by many constructional and operational limitations. The dynamic development of computer technology, enables using it for numerical simulation of changeable technical state processes.

  • influence of axial compressor Flow Passage Geometry changes on gas turbine engine work parameters
    Journal of Polish CIMAC, 2009
    Co-Authors: Paweł Wirkowski
    Abstract:

    The paper deals with the problem of influence of changes variable stator vanes axial compressor settings of gas turbine engine on work parameters of compressor and engine. Incorrect operation of change setting system of variable vanes could make unstable work of compressor and engine. This paper presents theoretical analysis of situation described above and results of own research done on real engine. On the base of results of experiment there were determined mathematical equations determining relationships of changes of particular engine work parameters in function of variable inlet guide stator vanes setting angle. There are presented results of the solution of mathematical equations, which describe the changes of engine work parameters values too.

  • Modelling the characteristics of axial compressor of variable Flow Passage Geometry, working in the gas turbine engine system
    Polish Maritime Research, 2007
    Co-Authors: Paweł Wirkowski
    Abstract:

    This paper concerns application of mathematical modelling methods to analyzing gas-dynamic processes in marine gas turbines. Influence of Geometry changes in axial compressor Flow Passage on kinematical air Flow characteristics, are presented. The elaborated mathematical model will make it possible to realize - in the future - simulative investigations of gas-dynamic processes taking place in a compressor fitted with controllable guide vanes.

Allan J. Organ - One of the best experts on this subject based on the ideXlab platform.

  • Flow Passage Geometry
    The Air Engine, 2007
    Co-Authors: Allan J. Organ
    Abstract:

    The geometric feature, isolated gauze aperture, alone forms the boundary conditions determining the dynamics of the entire Flow. There is no evidence that the performance of air engines yet owes much to detailed attention to regenerator design. Power-producing potential being in terms of heat-rate in minus heat rate out, the “thermal bottleneck” evidently lies elsewhere than with the regenerator. As and when this restriction is eliminated, small changes in regenerator specification may be expected to result in a marked change in performance. Geometric design will then assume its due importance. If the wire-gauze regenerator prevails, it may be anticipated that the trend will be toward high values of aperture ratio. Within a class of matrices (gauzes of given weave) a single numerical parameter suffices to distinguish between Flow Passage geometries and, therefore, serves for the acquisition of experimental Flow data and its use in support of gas path design.

Willden Rhj - One of the best experts on this subject based on the ideXlab platform.

  • Designing multi-rotor tidal turbine fences
    Sustainable Energy Research Group, 2018
    Co-Authors: Cr Vogel, Willden Rhj
    Abstract:

    An embedded Reynolds-Averaged Navier-Stokes blade element actuator disk model is used to investigate the hydrodynamic design of tidal turbines and their performance in a closely spaced cross-stream fence. Turbines designed for confined Flows are found to require a larger blade solidity ratio than current turbine design practices imply in order to maximise power. Generally, maximum power can be increased by operating turbines in more confined Flows than they were designed for, although this also requires the turbines to operate at a higher rotational speed, which may increase the likelihood of cavitation inception. In-array turbine performance differs from that predicted from single turbine analyses, with cross-fence variation in power and thrust developing between the inboard and outboard turbines. As turbine thrust increases the cross-fence variation increases, as the interference effects between adjacent turbines strengthen as turbine thrust increases, but it is observed that cross-stream variation can be mitigated through strategies such as pitch-to-feather power control. It was found that overall fence performance was maximised by using turbines designed for moderately constrained (blocked) Flows, with greater blockage than that based solely on fence Geometry, but lower blockage than that based solely on the turbine and local Flow Passage Geometry to balance the multi-scale Flow phenomena around tidal fences

Cr Vogel - One of the best experts on this subject based on the ideXlab platform.

  • Designing multi-rotor tidal turbine fences
    Sustainable Energy Research Group, 2018
    Co-Authors: Cr Vogel, Willden Rhj
    Abstract:

    An embedded Reynolds-Averaged Navier-Stokes blade element actuator disk model is used to investigate the hydrodynamic design of tidal turbines and their performance in a closely spaced cross-stream fence. Turbines designed for confined Flows are found to require a larger blade solidity ratio than current turbine design practices imply in order to maximise power. Generally, maximum power can be increased by operating turbines in more confined Flows than they were designed for, although this also requires the turbines to operate at a higher rotational speed, which may increase the likelihood of cavitation inception. In-array turbine performance differs from that predicted from single turbine analyses, with cross-fence variation in power and thrust developing between the inboard and outboard turbines. As turbine thrust increases the cross-fence variation increases, as the interference effects between adjacent turbines strengthen as turbine thrust increases, but it is observed that cross-stream variation can be mitigated through strategies such as pitch-to-feather power control. It was found that overall fence performance was maximised by using turbines designed for moderately constrained (blocked) Flows, with greater blockage than that based solely on fence Geometry, but lower blockage than that based solely on the turbine and local Flow Passage Geometry to balance the multi-scale Flow phenomena around tidal fences