Specific volume of the superheated steam:

It is volume occupied by unit mass of superheated steam corresponding to given pressure of superheated steam generation. Superheated steam acts like a perfect gas. Therefore the law

is applicable to superheated steam. Let

v_g  = specific volume of dry saturated steam corresponding to given pressure of steam generation is m³ /kg.

T_S  = absolute saturation temperature corresponding to given pressure of steam generation.

T_sup  = absolute temperature of the superheated steam

P = pressure of steam generation

V_sup  = the required specific volume of superheated steam. Then, in above formula,