Zel'dovich number

The Zel'dovich number is a dimensionless number which provides a quantitative value for the activation energy of a chemical reaction which appears in the Arrhenius exponent, named after the Russian scientist Yakov Borisovich Zel'dovich.

It is defined as

where

In terms of heat release parameter ${\displaystyle \alpha }$, it is given by

For typical combustion phenomena, the value for Zel'dovich number lies in the range ${\displaystyle \beta \sim 8-20}$.

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