reg vol mesh
 

hai guyz i am havin a problem in meshing a design for the last 2 weeks .If anybody have any idea how to mesh please reply me soon . my main problem is, i designed a "hot water circuit" of a power plant to see the heat flow charecteristics from combustion to walls and from walls to the water in the pipes .i made 2 volumes 1 for water flow in the pipes 2nd for the solid walls .now i have 2 volumes and try to mesh both individually i didnt get any problem while i am meshing the 1st volume(i.e for water flow )but for the second one when iam tryin to mesh .it is meshing all the faces with out any errors but it is escaping(crashing) while it is going to take intialisation .its is showing (Initialisation Failed perturb boundary nodes,try again , check the skewness of faces where there are small gaps )is the message on transcript i am getting sometimes .i dont know reason whats the problem behind this .I tried with different intervals but it didnt worked out .I have a little doubt on the thickness of the tubes(solid walls), they are only about 4 mm thick in mydesign . I am willing to know about the mesh regarding a volume of very small thickness,I want to know if there is any relation between the dimensions of volume and meshing .If any body have any idea please reply me as soon as possible.