Hi

My problem involves variation of velocity as well as temperature at the inlet boundary condition(BC). I have a UDF for variation of velocity and plugged in the velocity inlet BC after interpreting it. AFter writing a UDF for temperature variation, I could not plug in this UDF in the momentum column of velocity inlet BC.

Velocity & Temperature varitaion UDF is written using DEFINE_PROFILE function.

Iam a new user of UDF.PLease help me. How to give both variations in single velocity inlet BC.

Regards Raj.

Dear Raj see example velocity profile should be writing this UDF in C_programing or C++ and save at as CPP extension file. after interpreting this UDF find it at boundary condition. with best regads emad **************************************** vprofile.c

UDF for specifying steady-state velocity profile boundary condition ************************************************** **********************/ #include "udf.h"

DEFINE_PROFILE(inlet_x_velocity, thread, position) { real x[ND_ND]; /* this will hold the position vector */ real y; face_t f;

begin_f_loop(f, thread)

{

F_CENTROID(x,f,thread);

y = x[1];

F_PROFILE(f, thread, position) = 20. - y*y/(.0745*.0745)*20.;

} end_f_loop(f, thread) }

Thanks Emad.

hOW TO USE EXPERIMENTAL data and not an equation, for time-dependent heat flux boundary condition ?

My data (of time and heat flux) are these listed below:

t [s] q" [w m^-2]

0.000000e+00 -5.987137e+01 2.220000e-01 -5.728233e+01 4.440000e-01 -5.685082e+01 6.660000e-01 -5.857685e+01 8.880000e-01 -5.943986e+01 1.110000e+00 -5.943986e+01 1.332000e+00 -6.246041e+01 1.554000e+00 -6.289192e+01 1.776000e+00 -6.548097e+01 1.998000e+00 -6.591247e+01 2.220000e+00 -6.763850e+01 2.442000e+00 -7.238508e+01 2.664000e+00 -7.195358e+01 2.886000e+00 4.954787e+02 3.108000e+00 2.687104e+03 3.330000e+00 4.489078e+03 3.552000e+00 6.102055e+03 3.774000e+00 7.009084e+03 3.996000e+00 6.729465e+03 4.218000e+00 7.354288e+03 4.440000e+00 8.421838e+03 4.662000e+00 9.476874e+03 4.884000e+00 1.042705e+04 5.106000e+00 1.126720e+04 5.328000e+00 1.199946e+04 5.550000e+00 1.264025e+04 5.772000e+00 1.320380e+04 5.994000e+00 1.370176e+04 6.216000e+00 1.413586e+04 6.438000e+00 1.452637e+04 6.660000e+00 1.487503e+04 6.882000e+00 1.518183e+04 7.104000e+00 1.545196e+04 7.326000e+00 1.570525e+04 7.548000e+00 1.593395e+04 7.770000e+00 1.613892e+04 7.992000e+00 1.632878e+04 8.214000e+00 1.650311e+04 8.436000e+00 1.666104e+04 8.658000e+00 1.680646e+04 8.880000e+00 1.694109e+04 9.102000e+00 1.706666e+04 9.324000e+00 1.718273e+04 9.546000e+00 1.728802e+04 9.768000e+00 1.738640e+04 9.990000e+00 1.747918e+04 1.021200e+01 1.756634e+04 1.043400e+01 1.764617e+04 1.065600e+01 1.772039e+04 1.087800e+01 1.779331e+04 1.110000e+01 1.785847e+04 1.132200e+01 1.791931e+04 1.154400e+01 1.797843e+04 1.176600e+01 1.803323e+04 1.198800e+01 1.808156e+04 1.221000e+01 1.813291e+04 1.243200e+01 1.817951e+04 1.265400e+01 1.822482e+04 1.287600e+01 1.826236e+04 1.309800e+01 1.830336e+04 1.332000e+01 1.834305e+04 1.354200e+01 1.837671e+04 1.376400e+01 1.841382e+04 1.398600e+01 1.844187e+04 1.420800e+01 1.847035e+04 1.443000e+01 1.849969e+04 1.465200e+01 1.852946e+04 1.487400e+01 1.855493e+04 1.509600e+01 1.857995e+04 1.531800e+01 1.860455e+04 1.554000e+01 1.862742e+04 1.576200e+01 1.865158e+04 1.598400e+01 1.867402e+04 1.620600e+01 1.869344e+04 1.642800e+01 1.871156e+04 1.665000e+01 1.873098e+04 1.687200e+01 1.874695e+04 1.709400e+01 1.876248e+04 1.731600e+01 1.877801e+04 1.753800e+01 1.879441e+04 1.776000e+01 1.880693e+04 1.798200e+01 1.882073e+04 1.820400e+01 1.883066e+04 1.842600e+01 1.884662e+04 1.864800e+01 1.885957e+04 1.887000e+01 1.887165e+04 1.909200e+01 1.888330e+04 1.931400e+01 1.889366e+04 1.953600e+01 1.890531e+04 1.975800e+01 1.891307e+04 1.998000e+01 1.892473e+04 2.020200e+01 1.892990e+04 2.042400e+01 1.894026e+04 2.064600e+01 1.895191e+04 2.086800e+01 1.895709e+04 2.109000e+01 1.896788e+04 2.131200e+01 1.897694e+04 2.153400e+01 1.898643e+04 2.175600e+01 1.899463e+04 2.197800e+01 1.900369e+04 2.220000e+01 1.901232e+04 2.242200e+01 1.902138e+04 2.264400e+01 1.902656e+04 2.286600e+01 1.903476e+04 2.308800e+01 1.904080e+04 2.331000e+01 1.904900e+04 2.353200e+01 1.905677e+04 2.375400e+01 1.906324e+04 2.397600e+01 1.907144e+04 2.419800e+01 1.907921e+04 2.442000e+01 1.908568e+04 2.464200e+01 1.909690e+04 2.486400e+01 1.910682e+04 2.508600e+01 1.910984e+04 2.530800e+01 1.911675e+04 2.553000e+01 1.912538e+04 2.575200e+01 1.913314e+04 2.597400e+01 1.914048e+04 2.619600e+01 1.914825e+04 2.641800e+01 1.915644e+04 2.664000e+01 1.916594e+04 2.686200e+01 1.917198e+04 2.708400e+01 1.917931e+04 2.730600e+01 1.919054e+04 2.752800e+01 1.919528e+04 2.775000e+01 1.920262e+04 2.797200e+01 1.921082e+04 2.819400e+01 1.921902e+04 2.841600e+01 1.923282e+04 2.863800e+01 1.923584e+04 2.886000e+01 1.924145e+04 2.908200e+01 1.924663e+04 2.930400e+01 1.925612e+04 2.952600e+01 1.926087e+04 2.974800e+01 1.926864e+04 2.997000e+01 1.927468e+04 3.019200e+01 1.928244e+04 3.041400e+01 1.928892e+04 3.063600e+01 1.929410e+04 3.085800e+01 1.930100e+04 3.108000e+01 1.930704e+04 3.130200e+01 1.930920e+04 3.152400e+01 1.931567e+04 3.174600e+01 1.931524e+04 3.196800e+01 1.932387e+04 3.219000e+01 1.932862e+04 3.241200e+01 1.933509e+04 3.263400e+01 1.933768e+04 3.285600e+01 1.933940e+04 3.307800e+01 1.934372e+04 3.330000e+01 1.934760e+04 3.352200e+01 1.935321e+04 3.374400e+01 1.935408e+04 3.396600e+01 1.936184e+04 3.418800e+01 1.936486e+04 3.441000e+01 1.937090e+04 3.463200e+01 1.937694e+04 3.485400e+01 1.937953e+04 3.507600e+01 1.938169e+04 3.529800e+01 1.938860e+04 3.552000e+01 1.938989e+04 3.574200e+01 1.939464e+04 3.596400e+01 1.940284e+04 3.618600e+01 1.940888e+04 3.640800e+01 1.941276e+04 3.663000e+01 1.941621e+04 3.685200e+01 1.941880e+04 3.707400e+01 1.942614e+04 3.729600e+01 1.943132e+04 3.751800e+01 1.943649e+04 3.774000e+01 1.943865e+04 3.796200e+01 1.944340e+04 3.818400e+01 1.945073e+04 3.840600e+01 1.945764e+04 3.862800e+01 1.946195e+04 3.885000e+01 1.946411e+04 3.907200e+01 1.947015e+04 3.929400e+01 1.947403e+04 3.951600e+01 1.948094e+04 3.973800e+01 1.948698e+04 3.996000e+01 1.949302e+04 4.018200e+01 1.950165e+04 4.040400e+01 1.951028e+04 4.062600e+01 1.951589e+04 4.084800e+01 1.952452e+04 4.107000e+01 1.953488e+04 4.129200e+01 1.954523e+04 4.151400e+01 1.955429e+04 4.173600e+01 1.956681e+04 4.195800e+01 1.957414e+04 4.218000e+01 1.957803e+04 4.240200e+01 1.958493e+04 4.262400e+01 1.959572e+04 4.284600e+01 1.960263e+04 4.306800e+01 1.960737e+04 4.329000e+01 1.961687e+04 4.351200e+01 1.961773e+04 4.373400e+01 1.962593e+04 4.395600e+01 1.963283e+04 4.417800e+01 1.963628e+04 4.440000e+01 1.964318e+04 4.462200e+01 1.964923e+04 4.484400e+01 1.965225e+04 4.506600e+01 1.965441e+04 4.528800e+01 1.965915e+04 4.551000e+01 1.966821e+04 4.573200e+01 1.966908e+04 4.595400e+01 1.967382e+04 4.617600e+01 1.967900e+04 4.639800e+01 1.967900e+04 4.662000e+01 1.968116e+04 4.684200e+01 1.967814e+04 4.706400e+01 1.968461e+04 4.728600e+01 1.968634e+04 4.750800e+01 1.968806e+04 4.773000e+01 1.969195e+04 4.795200e+01 1.969583e+04 4.817400e+01 1.969410e+04 4.839600e+01 1.969410e+04 4.861800e+01 1.969238e+04 4.884000e+01 1.968979e+04 4.906200e+01 1.969065e+04 4.928400e+01 1.969324e+04 4.950600e+01 1.969367e+04 4.972800e+01 1.969496e+04 4.995000e+01 1.969799e+04 5.017200e+01 1.969842e+04 5.039400e+01 1.969367e+04 5.061600e+01 1.969367e+04 5.083800e+01 1.969971e+04 5.106000e+01 1.969756e+04 5.128200e+01 1.969496e+04 5.150400e+01 1.969195e+04 5.172600e+01 1.969281e+04 5.194800e+01 1.968893e+04 5.217000e+01 1.968849e+04 5.239200e+01 1.968332e+04 5.261400e+01 1.968677e+04 5.283600e+01 1.968763e+04 5.305800e+01 1.968634e+04 5.328000e+01 1.968547e+04 5.350200e+01 1.968375e+04 5.372400e+01 1.968159e+04 5.394600e+01 1.967771e+04 5.416800e+01 1.967555e+04 5.439000e+01 1.967425e+04 5.461200e+01 1.967253e+04 5.483400e+01 1.967469e+04 5.505600e+01 1.967339e+04 5.527800e+01 1.966951e+04 5.550000e+01 1.966605e+04 5.572200e+01 1.966433e+04 5.594400e+01 1.966045e+04 5.616600e+01 1.966260e+04 5.638800e+01 1.965915e+04 5.661000e+01 1.965311e+04 5.683200e+01 1.965527e+04 5.705400e+01 1.965354e+04 5.727600e+01 1.965311e+04 5.749800e+01 1.965095e+04 5.772000e+01 1.965182e+04 5.794200e+01 1.965138e+04 5.816400e+01 1.964793e+04 5.838600e+01 1.964491e+04 5.860800e+01 1.964491e+04 5.883000e+01 1.964578e+04 5.905200e+01 1.964448e+04 5.927400e+01 1.964275e+04 5.949600e+01 1.963973e+04 5.971800e+01 1.963499e+04 5.994000e+01 1.963585e+04 6.016200e+01 1.963499e+04 6.038400e+01 1.963240e+04 6.060600e+01 1.962894e+04 6.082800e+01 1.962549e+04 6.105000e+01 1.962679e+04 6.127200e+01 1.962506e+04 6.149400e+01 1.962506e+04 6.171600e+01 1.962247e+04 6.193800e+01 1.961859e+04 6.216000e+01 1.961773e+04 6.238200e+01 1.961384e+04 6.260400e+01 1.960910e+04 6.282600e+01 1.960953e+04 6.304800e+01 1.960953e+04 6.327000e+01 1.961082e+04 6.349200e+01 1.939593e+04 6.371400e+01 1.808329e+04 6.393600e+01 1.648067e+04 6.415800e+01 1.494105e+04 6.438000e+01 1.355117e+04 6.460200e+01 1.230972e+04 6.482400e+01 1.121412e+04 6.504600e+01 1.024841e+04 6.526800e+01 9.393591e+03 6.549000e+01 8.633274e+03 6.571200e+01 7.974796e+03 6.593400e+01 7.371547e+03 6.615600e+01 6.828281e+03 6.637800e+01 6.337226e+03 6.660000e+01 5.897517e+03 6.682200e+01 5.498806e+03 6.704400e+01 5.136339e+03 6.726600e+01 4.805375e+03 6.748800e+01 4.499868e+03 6.771000e+01 4.221112e+03 6.793200e+01 3.974292e+03 6.815400e+01 3.739982e+03 6.837600e+01 3.519914e+03 6.859800e+01 3.321852e+03 6.882000e+01 3.133715e+03 6.904200e+01 2.964995e+03 6.926400e+01 2.801454e+03 6.948600e+01 2.652152e+03 6.970800e+01 2.512776e+03 6.993000e+01 2.378577e+03 7.015200e+01 2.253440e+03 7.037400e+01 2.136501e+03 7.059600e+01 2.028624e+03 7.081800e+01 1.928946e+03 7.104000e+01 1.832720e+03 7.126200e+01 1.743398e+03 7.148400e+01 1.657097e+03 7.170600e+01 1.577699e+03 7.192800e+01 1.499596e+03 7.215000e+01 1.425377e+03 7.237200e+01 1.355473e+03 7.259400e+01 1.289884e+03 7.281600e+01 1.225589e+03 7.303800e+01 1.168198e+03 7.326000e+01 1.109514e+03 7.348200e+01 1.056438e+03 7.370400e+01 1.004657e+03 7.392600e+01 9.558970e+02 7.414800e+01 9.075680e+02 7.437000e+01 8.670066e+02 7.459200e+01 8.273077e+02 7.481400e+01 7.858830e+02 7.503600e+01 7.453212e+02 7.525800e+01 7.095064e+02 7.548000e+01 6.741226e+02 7.570200e+01 6.357186e+02 7.592400e+01 6.046499e+02 7.614600e+01 5.714239e+02 7.636800e+01 5.416497e+02 7.659000e+01 5.136017e+02 7.681200e+01 4.842593e+02 7.703400e+01 4.588006e+02 7.725600e+01 4.294578e+02 7.747800e+01 4.044306e+02 7.770000e+01 3.837180e+02 7.792200e+01 3.595537e+02 7.814400e+01 3.336634e+02 7.836600e+01 3.133824e+02 7.858800e+01 2.931016e+02 7.881000e+01 2.710948e+02 7.903200e+01 2.525400e+02 7.925400e+01 2.374372e+02 7.947600e+01 2.188824e+02 7.969800e+01 2.029166e+02 7.992000e+01 1.878138e+02 8.014200e+01 1.705536e+02 8.036400e+01 1.524302e+02 8.058600e+01 1.360330e+02 8.080800e+01 1.248138e+02 8.103000e+01 1.114371e+02 8.125200e+01 9.547126e+01 8.147400e+01 8.468358e+01 8.169600e+01 7.346440e+01 8.191800e+01 6.353974e+01 8.214000e+01 5.102603e+01 8.236200e+01 3.980684e+01 8.258400e+01 3.074517e+01 8.280600e+01 2.082051e+01 8.302800e+01 9.601328e+00 8.325000e+01 -7.548738e-01 8.347200e+01 -1.067953e+01 8.369400e+01 -1.801516e+01 8.391600e+01 -2.837134e+01 8.413800e+01 -3.786450e+01 8.436000e+01 -4.822067e+01 8.458200e+01 -5.383027e+01 8.480400e+01 -5.900836e+01 8.502600e+01 -6.893303e+01 8.524800e+01 -7.756317e+01 8.547000e+01 -8.446729e+01 8.569200e+01 -9.180291e+01 8.591400e+01 -9.870705e+01 8.613600e+01 -1.051797e+02 8.635800e+01 -1.146728e+02 8.658000e+01 -1.220084e+02 8.680200e+01 -1.315016e+02 8.702400e+01 -1.366797e+02 8.724600e+01 -1.444468e+02 8.746800e+01 -1.504879e+02 8.769000e+01 -1.586866e+02 8.791200e+01 -1.582551e+02 8.813400e+01 -1.647277e+02 8.835600e+01 -1.668852e+02 8.857800e+01 -1.729263e+02 8.880000e+01 -1.776729e+02 8.902200e+01 -1.863030e+02 8.924400e+01 -1.875975e+02 8.946600e+01 -1.914811e+02 8.968800e+01 -1.919126e+02 8.991000e+01 -1.970907e+02 9.013200e+01 -1.979537e+02 9.035400e+01 -2.074469e+02 9.057600e+01 -2.070154e+02 9.079800e+01 -2.065839e+02 9.102000e+01 -2.096044e+02 9.124200e+01 -2.165085e+02 9.146400e+01 -2.186661e+02 9.168600e+01 -2.234127e+02 9.190800e+01 -2.242757e+02 9.213000e+01 -2.311798e+02 9.235200e+01 -2.311798e+02 9.257400e+01 -2.307483e+02 9.279600e+01 -2.324743e+02 9.301800e+01 -2.354949e+02 9.324000e+01 -2.367894e+02 9.346200e+01 -2.428305e+02 9.368400e+01 -2.428305e+02 9.390600e+01 -2.480086e+02 9.412800e+01 -2.484401e+02 9.435000e+01 -2.497346e+02 9.457200e+01 -2.514606e+02 9.479400e+01 -2.540497e+02 9.501600e+01 -2.583647e+02 9.523800e+01 -2.618168e+02 9.546000e+01 -2.639743e+02 9.568200e+01 -2.652689e+02 9.590400e+01 -2.652689e+02 9.612600e+01 -2.682894e+02 9.634800e+01 -2.687209e+02 9.657000e+01 -2.682894e+02 9.679200e+01 -2.730360e+02 9.701400e+01 -2.738990e+02 9.723600e+01 -2.743305e+02 9.745800e+01 -2.726045e+02 9.768000e+01 -2.743305e+02 9.790200e+01 -2.756250e+02 9.812400e+01 -2.786456e+02 9.834600e+01 -2.790771e+02 9.856800e+01 -2.829607e+02 9.879000e+01 -2.808031e+02 9.901200e+01 -2.833922e+02 9.923400e+01 -2.842552e+02 9.945600e+01 -2.902963e+02 9.967800e+01 -2.907278e+02 9.990000e+01 -2.907278e+02 1.001220e+02 -2.924538e+02 1.003440e+02 -2.937483e+02 1.005660e+02 -2.933169e+02 1.007880e+02 -2.937483e+02 1.010100e+02 -2.937483e+02 1.012320e+02 -2.928854e+02 1.014540e+02 -2.937483e+02 1.016760e+02 -2.941798e+02 1.018980e+02 -2.946114e+02 1.021200e+02 -2.954744e+02 1.023420e+02 -2.967689e+02 1.025640e+02 -2.950429e+02 1.027860e+02 -2.967689e+02 1.030080e+02 -2.937483e+02 1.032300e+02 -2.993580e+02 1.034520e+02 -2.980634e+02 1.036740e+02 -3.015155e+02 1.038960e+02 -2.980634e+02 1.041180e+02 -3.002209e+02 1.043400e+02 -3.019470e+02 1.045620e+02 -3.015155e+02 1.047840e+02 -3.023785e+02 1.050060e+02 -3.032415e+02 1.052280e+02 -3.028100e+02 1.054500e+02 -3.036730e+02 1.056720e+02 -3.023785e+02 1.058940e+02 -3.079881e+02 1.061160e+02 -3.088511e+02 1.063380e+02 -3.097141e+02 1.065600e+02 -3.097141e+02 1.067820e+02 -3.084196e+02 1.070040e+02 -3.088511e+02 1.072260e+02 -3.105772e+02 1.074480e+02 -3.105772e+02 1.076700e+02 -3.110087e+02 1.078920e+02 -3.118717e+02 1.081140e+02 -3.105772e+02 1.083360e+02 -3.092826e+02 1.085580e+02 -3.118717e+02 1.087800e+02 -3.183443e+02 1.090020e+02 -3.187758e+02 1.092240e+02 -3.183443e+02 1.094460e+02 -3.183443e+02 1.096680e+02 -3.209333e+02 1.098900e+02 -3.209333e+02 1.101120e+02 -3.209333e+02 1.103340e+02 -3.213648e+02 1.105560e+02 -3.209333e+02 1.107780e+02 -3.209333e+02

Note: i don´t use an equation!