Stretched Grids
 

Hi everyone,

I had this doubt in the stretched grid topic.
we have the two planes namely
a) physical plane
b) computational plane

horizontal spacing is same in both the planes ie. x=episilon
but the vertical spacing in physical plane is a variable, it increases.
according to the j.d.andreson book n=ln(y+1)

where n is the uniform vertical spacing in the computational plane
when we solve the above equation we get
del(y)=e^n * del(n)

consider an example where the values for y are 1,3,6,10,15
with reference to these values of 'y' the values of n thus obtained doesn't satisfy the relation that del(n) is const. ie. the grid is equally spaced.

can anyone explain me where im going wrong..!