Hello,

I'm trying to write a code using SIMPLE on staggered cartesian grids. The books I read mention that u,v,p each are solved on their control volume.

However, all the examples are given on uniform grids. What if the grid are non-uniform?

If the p nodes are defined on the center of its control volume, is it correct to say that the u nodes will be on the left, right faces of the p control volume?

In that case, is the left,right faces of the u control volume on the same location as the p nodes? But if that's the case, u will not be in the center of its own control volume.

Or the p nodes do not coincide with the left, right faces of the u control volume and u is at the center of its own control volume.

Which one is correct? Or can both be used? Is there any preferred choice? Thank you.

the type of scheme you apply is important. and you have to use weighted interpolation.

for a 1d problem let's say, two adjacent p control volumes will have lengths delta_x_1 and delta_x_2. the u control volume will thus have length 1/2(delta_x_1 + delta_x_2). is that the confusion? in the program have one delta_x array and subsequently when the delta_x of p cv is required, use that starightway. when the delta_x of the u cv is required, go by the algebra as above. remember delta_x_1/delta_x_2 ratio (larger/smaller) should not exeed 1.2 or so, if delta_x_1 is larger.