The Optimum Theoretical Design of Ranque-Hilsch Vortex Tube by using a Technique of Multiple Attribute Decision Making

The vortex tube is one of the devices used in refrigeration and air conditioning. This device is characterized by many features, including ease of manufacture, low cost, no need of maintenance, and does not produce any harmful waste for the environment, also rather it is one of the applications of environmentally friendly renewable energies. The Ranque _Hilsch vortex tube is used in medical purposes, the airplane cabins, cooling or heating of gases, and gases component separation. In present research, a theoretical and numerical study has been prepared to predict the expected temperature of the vortex tube according to the following variables: inlet pressure range (1.5-6.0 bar), the length-to-diameter ratio is 10, 13, 16 and19, and the ratio of mass cold air to the interior air is 0.2, 0.4, 0.6, and 0.8. Also, the multi-attribute decision-making technique (MADM) was used to rearrange the results that were studied according to the importance of parameters and available data. According to Weighted Sum Method (WSM) and Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) the optimize choice at L/d = 13 with temperature drop 69.6 °C, pressure 6 bar, cold mass fraction µ = 0.2 and COP = 0.09127, by Weighted Product Method (WPM) the results showed that the optimum choice at L/d = 13 with temperature drop 62.6 °C, pressure 6 bar, cold mass fraction µ = 0.4 and COP = 0.16312