Minor addition.

git-svn-id: https://svn.dealii.org/trunk@24382 0785d39b-7218-0410-832d-ea1e28bc413d

diff --git a/deal.II/examples/step-32/doc/intro.dox b/deal.II/examples/step-32/doc/intro.dox
index 2212c3855d36c53dc4965e151234df09e07382f5..2ebf075a0967dca10567f59691fe7ec87aabbebe 100644 (file)
--- a/deal.II/examples/step-32/doc/intro.dox
+++ b/deal.II/examples/step-32/doc/intro.dox
@@ -91,7 +91,9 @@ with which the Stokes equations would read:
 This is exactly the form we used in step-31, and it was
 appropriate to do so because all changes in the fluid flow are only
 driven by the dynamic pressure that results from temperature
-differences.
+differences. (In other words: Any contribution to the right hand side
+that results from taking the gradient of a scalar field have no effect
+on the velocity field.)
 
 On the other hand, we will here use the form of the Stokes equations
 that considers the total pressure instead: