Temperature separation and friction losses in vortex tube

The process of energy separation and friction losses in a vortex tube is studied in detail. The hot and cold exit air temperatures were measured. Experiments have been conducted at inlet pressure of 3.5, 5, 7.5 and 9 bar, at inlet temperature of 292.15 and 298.15 K and at cold air mass ratio from 0 to1. The results demonstrate that the hot air temperature reaches its maximum value at a cold air mass ratio of nearly 0.82, while the minimum value of cold air temperature is found at a cold air mass ratio of 0.3. Based on energy and mass balances as well as on the definition of internal energy and on experimental results a new model for the determination of hot and cold exit gas temperature has been developed. The model includes the relevant primary parameters and predicts the experimental results as well as the data published in the literature sufficiently accurate for engineering purposes.A cross-section area m³ - D diameter of the pipe m - F model parameter - f friction factor - L length of the tube m - m mass flow rate kg/s - y cold air mass ratio - P static pressure Pa - T temperature K - t thickness of the orifice m - R gas constant J/kg K - v velocity of fluid m/s - density of the fluid kg/m³ - friction factor for pipe - friction factor for orifice and tee junction - 1 inlet of compressed gas - 2 exit of hot gas - 3 exit of cold gas - atm atmospheric pressure - c cold exit gas - f friction - h hot exit gas - o orifice plate - T tee junction