<div dir="ltr"><span style="color:rgb(0,0,0);font-family:Verdana,Arial,Helvetica,sans-serif;font-size:13px;background-color:rgb(232,232,232)">Hi,</span><br style="color:rgb(0,0,0);font-family:Verdana,Arial,Helvetica,sans-serif;font-size:13px;background-color:rgb(232,232,232)">
<br style="color:rgb(0,0,0);font-family:Verdana,Arial,Helvetica,sans-serif;font-size:13px;background-color:rgb(232,232,232)"><span style="color:rgb(0,0,0);font-family:Verdana,Arial,Helvetica,sans-serif;font-size:13px;background-color:rgb(232,232,232)">I have a problem with something a priori easy to calculate but in which I really don't succeed to do...</span><br style="color:rgb(0,0,0);font-family:Verdana,Arial,Helvetica,sans-serif;font-size:13px;background-color:rgb(232,232,232)">
<br style="color:rgb(0,0,0);font-family:Verdana,Arial,Helvetica,sans-serif;font-size:13px;background-color:rgb(232,232,232)"><span style="color:rgb(0,0,0);font-family:Verdana,Arial,Helvetica,sans-serif;font-size:13px;background-color:rgb(232,232,232)">I want to calculate a heat flux in a flat plate (with a thickness) and so I calculate the gradient of the temperature (with GradientOfUnstucturedDataSet). In then take the component of the gradient which is normal to the face I want to have the heat flux.</span><br style="color:rgb(0,0,0);font-family:Verdana,Arial,Helvetica,sans-serif;font-size:13px;background-color:rgb(232,232,232)">
<br style="color:rgb(0,0,0);font-family:Verdana,Arial,Helvetica,sans-serif;font-size:13px;background-color:rgb(232,232,232)"><span style="color:rgb(0,0,0);font-family:Verdana,Arial,Helvetica,sans-serif;font-size:13px;background-color:rgb(232,232,232)">In the solid, the values given are good (non zero) and equal to the theoretical values, ok...</span><br style="color:rgb(0,0,0);font-family:Verdana,Arial,Helvetica,sans-serif;font-size:13px;background-color:rgb(232,232,232)">
<br style="color:rgb(0,0,0);font-family:Verdana,Arial,Helvetica,sans-serif;font-size:13px;background-color:rgb(232,232,232)"><span style="color:rgb(0,0,0);font-family:Verdana,Arial,Helvetica,sans-serif;font-size:13px;background-color:rgb(232,232,232)">But when I want to show the normal component of gradient on a boundary face by using ExtractBlock and then ExtractSurface, the values of the gradient are 0 everywhere... But in the volume it is still non zero !</span><br style="color:rgb(0,0,0);font-family:Verdana,Arial,Helvetica,sans-serif;font-size:13px;background-color:rgb(232,232,232)">
<br style="color:rgb(0,0,0);font-family:Verdana,Arial,Helvetica,sans-serif;font-size:13px;background-color:rgb(232,232,232)"><span style="color:rgb(0,0,0);font-family:Verdana,Arial,Helvetica,sans-serif;font-size:13px;background-color:rgb(232,232,232)">Here are pictures showing the problem. In the first image, I plot the temperature on a flat plate (with thickness) and I calculate the gradient. I have compared to the theorical values and it is okay.</span><br style="color:rgb(0,0,0);font-family:Verdana,Arial,Helvetica,sans-serif;font-size:13px;background-color:rgb(232,232,232)">
<br style="color:rgb(0,0,0);font-family:Verdana,Arial,Helvetica,sans-serif;font-size:13px;background-color:rgb(232,232,232)"><span style="color:rgb(0,0,0);font-family:Verdana,Arial,Helvetica,sans-serif;font-size:13px;background-color:rgb(232,232,232)">In the second image, I wanted to plot the value of the gradient in a boundary face of the flat plate but I have 0 everywhere...(which is however calculated in the volume... I have also tried to project the values by using "PointDataToCellData" and "Cell centers" but it doesn't work...</span><br style="color:rgb(0,0,0);font-family:Verdana,Arial,Helvetica,sans-serif;font-size:13px;background-color:rgb(232,232,232)">
<br style="color:rgb(0,0,0);font-family:Verdana,Arial,Helvetica,sans-serif;font-size:13px;background-color:rgb(232,232,232)"><span style="color:rgb(0,0,0);font-family:Verdana,Arial,Helvetica,sans-serif;font-size:13px;background-color:rgb(232,232,232)">Is it a bug ?</span><br style="color:rgb(0,0,0);font-family:Verdana,Arial,Helvetica,sans-serif;font-size:13px;background-color:rgb(232,232,232)">
<span style="color:rgb(0,0,0);font-family:Verdana,Arial,Helvetica,sans-serif;font-size:13px;background-color:rgb(232,232,232)">I'm using Paraview 4.0 on ubuntu 12.10.</span><br></div>