Numerical CFD analysis and experimental investigation of the geometric performance parameter influences on the counter-flow Ranque-Hilsch vortex tube (C-RHVT) by using optimized turbulence model

Abstract

This research article demonstrates how using different turbulence models may affect the temperature detachment (the temperature diminution of cold air (∆Tc = Ti − Tc)) inside straight counter-flow Ranque-Hilsch Vortex Tube (RHVT). The code is utilized to find the optimized turbulence model for energy separation by comparison with the experimental data of the setup. To obtain the results with a minimum error, various turbulence models have been investigated in steady state and transient time-dependence modes. Results show that RNG k-e turbulence model has the best correspondence with the obtained experimental data from the setup; therefore, by using a RNG k-e turbulence model with respect to Finite Volume Method (FVM), all the computations have been carried out. Moreover, some geometric parameters are focused on the length of hot tube and number of nozzle intakes within divergent and convergent hot-tube. Numerical results present that there is an optimum angle for obtaining the highest refrigeration performance, and 2ο divergence is the optimal candidate under our numerical analysis conditions. Length of hot tube which exceeds a critical length has slight effect on the refrigeration capacity. The critical length is L = 166 mm in our study. Temperature reduction sensitivity can be reduced by increasing number of nozzles and maximum temperature reduction can be obtained.