Expansierratio

Expansierratio is not a term with a single, universally accepted definition in published technical literature. It appears to be a compound formed from “expansion” and “ratio” and is occasionally encountered as a nonstandard label or identifier in texts, datasets, or software documentation. Because there is no consensus on its meaning, the precise interpretation of expansierratio depends on context; in many cases it is intended as a variant of expansion ratio.

In thermodynamics and fluid mechanics, expansion ratio typically refers to the ratio of a system’s final volume to its initial volume during expansion (ER = V_final / V_initial). In nozzles and turbines, expansion ratio can also describe the geometric ratio of exit area to throat area, which governs the expansion of the working fluid. In internal combustion engines, the term expansion ratio is used to describe how much the gas expands during the power stroke, often related to, but distinct from, the compression ratio.

Because expansierratio is not standardized, researchers and practitioners should verify its meaning from the specific source. If used as a variable name, expansierratio may denote a ratio of expanded to unexpanded quantities in a calculation or simulation, but definitions will vary by software and study.

See also: expansion ratio, compression ratio, nozzle expansion, turbine expansion, thermodynamics, fluid mechanics.