EXPERIMENTAL STUDIES OF HIGH-SPEED LIQUID FILMS …：高速液体薄膜的实验研究….pptVIP

Outline Porous Gas Cooled Divertors Porous Gas Cooled DivertorsObjective Compare predictions of the MERLOT code against FLUENT (6.1.22) predictions Assess impact of using the incompressible fluid continuity equation on MERLOT’s Predictions Porous Gas Cooled Divertors Test Problem Definition FLUENT has been used to solve the conservation equations (mass, momentum, and energy) Assumptions Laminar flow Isotropic porosity Either incompressible or compressible flow Local thermodynamic equilibrium between the gas and solid matrix Two-dimensional (r, ?) 60?754 grid for r and ? directional resolution Porous Gas Cooled Divertors  Effective Heat Transfer Coeffcient Porous Gas Cooled Divertors  Temperature Distribution Porous Gas Cooled Divertors Pressure Drop Porous Gas-Cooled DivertorsPreliminary Conclusions Thin-Liquid-Protected DivertorsObjective This work is aimed at establishing limits for the maximum allowable temperature gradients (i.e. heat flux gradients) to prevent film rupture due to thermocapillary effects Thin-Liquid-Protected Divertors Problem Definition Initially, quiescent liquid and gas (u=0, v=0, T=Tm at t=0) Thin-Liquid-Protected Divertors Numerical Method Evolution of the free surface is modeled using the Level Contour Reconstruction Method Two Grid Structures Volume - entire computational domain (both phases) discretized by a standard, uniform, stationary, finite difference grid. Phase Interface - discretized by Lagrangian points or elements whose motions are explicitly tracked.  Thin-Liquid-Protected Divertors Governing Equations A single field formulation Constant but unequal material properties Surface tension included as local surface delta function sources NUMERICAL METHOD Thin Liquid-Protected DivertorsPreliminary Conclusions Preliminary Assessment of Porous Gas-Cooled and Thin-Liquid-Protected DivertorsS. I. Abdel-Khalik, S. Shin, and M. Yoda ARIES Meeting, UCSD (March 2004) G. W. Woodruff School of Mechanical Engin