Rao in the late 1950's devised a simple geometric approximation to an
'ideal' bell nozzle. He called it the 'Thrust Optimised Parabolic (TOP)
nozzle' because he used a skewed parabola as the bell.
I've looked for ages for a mathematical description of that skewed
parabola, then a guy on GitHub said "You realise that in Europe we call
that skewed parabola a quadratic Bezier curve."
He's right, it is a quadratic Bezier, and Wikipedia (correctly) gives the
simple formula for its construction.
I've written this up as a paper on the Aspire website:
www.aspirespace.org.uk/technical_papers.html
Rick the Rocketeer
