Propeller Cavitation Number - Inception

Cavitation number σ_n at a given depth and rpm compared to the empirical inception threshold - the first check before Burrill / Keller chart assessment.

CavitationPropellerInception

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This calculator requires JavaScript to compute its result. The formula, symbols, and regulatory sources are shown in the Formula section below.

Formula, assumptions, and limits

\sigma_n = \frac{p_a + \rho g h - p_v}{\tfrac{1}{2} \rho V_t^2}

Symbol	Meaning	Unit
$p_a$	Atmospheric pressure	Pa
$h$	Shaft depth	m
$p_v$	Water vapour pressure @ T	Pa
$V_t$	Tip speed	m/s

Source: Burrill L.C. - RINA 1943; Keller J. - 1966

In short

Cavitation number \u03c3_n at a given depth and rpm compared to the empirical inception threshold - the first check before Burrill / Keller chart assessment.

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