Answer to Question #310243 in Mechanical Engineering for jul

Question

28. Compute the specific volume of an air-vapor mixture in cubic meters pre kilogram of dry air when the following conditions prevail : t = 45oC, w = 0.015 kg/kg, and Pt = 100 kPa.

Answer 1

W = 0.622p_s /(p_t - p_s)

0.015 = 0.622p_s /(100 - p_s)

p_s = 2.355 kPa

p_a = p_t - p_s = 100 - 2.355 = 97.465 kPa

V_a = RT_a / p_a = (0.287)(45+237) / 97.465 = 0.83 m³/kg