About Beale Number

Beale Number, Bn is defined a next formula.

Bn = Ls / P V N

[Ls is a shaft power (Watt), P is a mean gas pressure (bar), V is swept volume of a expansion piston (cm3), and N is an engine speed (Hz).]

Most of high performance Stirling engines are said that Beale Number become 0.015. Then the shaft power of the Stirling engine is able to be given a next formula.

Ls = 0.015 P V N

I can calculate the shaft power easily using the above formula when I set P, V and N. But Bn=0.015 is used when I calculate a shaft power of high performance Stirling engines. I use Bn=0.011 for my model Stirling engines. It is caused by my experience and feeling.

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