Air filmcooling through laser drilled nozzles STW project CASA-dag Outline of the presentation 1.Introduction 2.Current situation 3.Local Uniform Grid Refinement 4.Boundary conditions 5.Conclusions and future plans Introduction Film cooling holes can be drilled by electro-discharged drilling laser drilling Laser drilling is a fast but crude process Cooling effectivity depends on detailed flow-structure Problem of interest Apparatus and Measurements Techniques The water channel with the glass test section (2.00 x 0.57 x 0.45 m) The interaction of the cross flow and the inclined jet over the flat plate Measurements technique Particle Image Velocimetry PIV Laser Induced Fluorescence - LIF Visualization Liquide Crystal Thermography - LCT Water channel at the TU/e The water channel and the set-up for the inclined jet = 35 0 U = 0.20m/s U jet is adjusable Coherent Structures in a Jet Crossflow Interaction Vertical laser sheet Averaged velocity in the inner-torus case VR=0.45 Current situation Compressible Navier-Stokes DNS code Parallel Fortran code for Silicon Graphics and Beowulf Cluster Problem Need more resolution in high activity area Answer (simple) Buy bigger computer Answer (smart) Local grid refinement two grid LUGR algorithm Smart answer - two grid LUGR algorithm LUGR algorithm GlobalcoarseGridGlobalcoarseGrid LocalfineGridLocalfineGrid Boundary conditions Substitution Dirichlet BC from the coarse grid Using physical variables (velocity, pressure, etc.) Using acoustical quantities (directions and amplitudes of the incoming and outgoing waves) Boundary conditions for the fine grid Results of calculation Composite grid Equivalent uniform fine grid Results of calculation Computation time Results of computation Real: ? Simple: Parabolic linear Boundary conditions jet profile Boundary conditions at walls Velocity and temperature profile at nozzles exit DNS code Unstructured solver Boundary conditions jet profile Imperfections Horizontal (x) velocity Vertical (y) velocity Some results 1.All three velocity components are present 2.Profiles differ from parabolic, specially for inaccuracies close to the exit 3.Qualitative agreement between experimental and numerical results Summary 1.Size blockage 2.Position better have inaccuracies away from the exit 3.Shape small influence Boundary conditions some conclusions Conclusions 1.Local grid refinement. 2.First results for inflow profiles. Different imperfections Influence of size, shape, position Future plans (next 1.5 months) 1.Back substitution of inflow profiles. 2.Comparison of the heat fluxes with experiments. Questions?