have a look here, page 47 :
https://www.aia.rwth-aachen.de/vlueb.../Vorlesung.pdf
Well, i acually found the corresponding study:
https://d-nb.info/1071469363/34
That looks like an analytical solution of a rotational symmetric problem which does not seem to be a good approach on a velomobile (but a good one for a submarine).