摘要

In the present study, an attempt is made to evaluate the effect of certain geometrical parameters on cooling performance of Ranque-Hilsch vortex tube (RHVT). Number of intakes in nozzle "n", cold orifice diameter "d(c)" and inlet pressure "P-i" are selected as influencing parameters at different levels n = 1, 2, 3; d(c) = 7, 9, 11 mm and P-i = 2, 2.5, 3 bar. The experiments are conducted based on three factors, two levels and central composite face centered design (CCF) with full factorial. The results are analyzed according to the principle of Response Surface Methodology (RSM). The equation to the response surface is developed using the design of experiments features of the commercial software package MINITAB-16. The goodness of fit of the regression model is examined using the Analysis of Variance (ANOVA) and the F-ratio test. The values of R-2 and R-2(adj.) are close to 100% which shows a very high correlation between the observed and predicted values. Results show sensitivity value of Delta T-c,T-max respect to n is negative (partial derivative Re/partial derivative A < 0). It means that increasing in n cause decreasing in Delta T-c,T-max and for low orifice diameter it has significant effect. The cold orifice diameter has more effect on Delta T-c,T-max. Its sensitivity value is 65.8% and 51.1% more than n and P-i, respectively. It is shown that for d*(c) < 0.5, (d*(c) = d(c)/D), increasing d*(c) causes the cold air temperature difference to increase and for d*(c) > 0.5, increasing d*(c) tends the cold air temperature difference to decrease.

  • 出版日期2014-6

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