Thanks for those hints folks, I shall look for a copy of that book Aerbabe recommends - although with a 1st September date that may be optimistic.
Yes - it's a transfer viva. The university in question (and my supervisor) have a slightly odd approach of submitting a transfer thesis which is about 80% of the total work, then submit the final thesis about 6 months later.
I probably have a slight advantage in that a fair chunk of the in-use published material in the field has my name on it anyway. One thing that troubles me slightly, and I don't know if anybody else has been there, is that whilst most of the work is experimental and virtually all of my analysis is nondimensionalised longhand calculation - virtually all of the published work by my assessors is CFD related. I confess to a mild paranoia about the risk of spending several hours defending the fact that I didn't do the whole lot by computer modelling.
G