Settings

Now showing1 - 6 of 6
  • Some of the metrics are blocked by your 
    consent settings
    Item type:Publication, Access status: without files ,
      96
  • Some of the metrics are blocked by your 
    consent settings
    Item type:Publication, Access status: without files ,
    Efficient Prediction of Crashback Performance of Controllable Pitch Propellers
    (2017-06)
    Pergande, Markus Friedrich
    ;
    Wang, Keqi
    ;
    Neitzel-Petersen, Jan Clemens
    ;
    Abdel-Maksoud, Moustafa
    The prediction of propeller performance in crashback con-ditions with numerical methods is challenging due to thehighly unsteady flow field, which is dominated by large-scale separation and recirculation regions. For a controllable pitch propeller (CPP), the computations should becarried out for a wide range of pitch angles. Reynolds Averaged Navier-Stokes (RANS) methods are not capable ofcapturing the most complex flow conditions. Hence, moreprecise methods like Detached Eddy Simulations (DES)should be applied. The high computational effort in conjunction with the application of these methods demands astrong limitation of the number of investigated operation points. In this paper, the computed open water characteristics curves of a CPP are compared with the experimental results. Thereby, the ranges of the open water diagram areidentified, where the RANS methods yield unsatisfying results. In these ranges, DES simulations are carried out tocapture the flow details on a propeller in crashback operation condition. DES results are shown to be in good agreement with the experimental data of the thrust and torque coefficient.
    Publicationtype: Conference Paper
      76
  • Some of the metrics are blocked by your 
    consent settings
    Item type:Publication, Access status: without files ,
      77
  • Some of the metrics are blocked by your 
    consent settings
    Item type:Publication, Access status: without files ,
      63
  • Some of the metrics are blocked by your 
    consent settings
    Item type:Publication, Access status: without files ,
    Entwicklung von panMARE als Paneelverfahren für interdisziplinäre maritime Anwendungen
    (2016)
    Abdel-Maksoud, Moustafa
    ;
    Alesbe, Israa
    ;
    Berger, Stephan
    ;
    Ferreira Gonzales, Daniel
    ;
    Göttsche, Ulf
    Computational methods based on the potential flow theory are common powerful tools for calculating the hydrodynamic behavior of lifting and non-lifting bodies. Potential flow methods can provide a valuable support for applications, where the pressure forces are dominant. Beside their short computing time, the accuracy of the results is mostly adequate for design purposes. Potential computational methods can also be used to simulate complex operation scenarios such as installation of offshore wind turbine involving different ship units. The development of computational methods for potential flow is usually carried out as problem-specific codes, i.e., certain methods are suitable only for a certain class of problems such as propeller flow or wave making resistance applications. In order to avoid this limitation, the development of a panel method panMARE was initiated several years ago at the Institute for Fluid Dynamics and Ship Theory, Hamburg University of Technology. A key point in the development of panMARE is the interdisciplinary applicability of the method for steady and unsteady flow problems under consideration of different physical models such as cavitation or influence of a free water surface. The motion of the investigated bodies can be either specified or calculated by solving the equation of motions. In addition panMARE has interfaces to various RANS solvers, thus it can be used in RANS-BEM simulations, as well as an interface to solvers that address structural and mechanical problems. Therefore, the method can be used to carry out coupled fluid-structure simulations. After explaining the theoretical background of the numerical method its capability will be demonstrated. In addition to typical shipbuilding problems such as calculation of propeller cavitation, pressure fluctuations or maneuver simulation in waves, different applications in the field of offshore wind energy will be presented.
    Publicationtype: Conference Paper
      133
  • Some of the metrics are blocked by your 
    consent settings
    Item type:Publication, Access status: without files ,
    Testing a semi-automated tool for the optimisation of full-scale marine propellers working behind a ship
    (Internat. Center for Numerical Methods in Engineering, 2013)
    Berger, Stephan
    ;
    Druckenbrod, Markus
    ;
    Pergande, Markus Friedrich
    ;
    Abdel-Maksoud, Moustafa
    A procedure for the optimization of full-scale marine propellers working be-hind a ship ispresented. This procedure consists of two stages: the actual optimization and a detailed investigation of a few selected propeller geometry variants. In the first step, an evolutionary algorithm in combination with the in-house panel code panMARE is used to solve the multi-objective propeller optimization problem. An efficient method for the evaluation of the individuals and a parameterization strategy for propeller shapes are presented. Proceeding from the results of the optimisation, a set of selected propeller variants is investigated in detail in the second stage of the procedure. The applied algo-rithm is based on coupling panMARE with a viscous flow solver. An enhancement of this method allows investigating several propeller variants sequentially without stopping the solvers.
    Publicationtype: Conference Paper
      77