ISSN Online: 2688-7231
ISBN Online: 978-1-56700-478-6
Proceedings of the 24th National and 2nd International ISHMT-ASTFE Heat and Mass Transfer Conference (IHMTC-2017)
A COMBINED HEAT AND MASS TRANSFER MODEL FOR THE RANQUE HILSCH VORTEX TUBE
Abstract
The aim of the present work is to introduce a new mathematical model that can predict the heat and mass transfer in a counter current Ranque Hilsch Vortex Tube (RHVT). RHVTs are widely used for spot cooling or heating and also found its use in mass separation applications. The physical behaviour of the flow inside the RHVT is not yet fully understood due to several complex and intriguing phenomenon encompassing the fields of fluid dynamics, mass transfer, heat transfer and thermodynamics. Experimental investigation of heat and mass transfer phenomenon in a RHVT is presented in previous publications by Chatterjee et. al. [1, 2]. A tangential
injection of a compressed gas mixture into the vortex chamber
of the RHVT results in a vortex motion within the tube, and two
streams (cold and hot) are withdrawn at opposite end of the
RHVT. Thermal as well as species separation is observed
between these two outlet streams. The present theoretical
model requires inlet conditions of the gas mixture and cold
outlet to inlet flow ratio. It can predict thermal gradient in hot and cold streams and concentration gradient of both enriched and depleted streams along the length of the RHVT. The well established Chilton Colburn analogy is used within its
applicable range to determine the mass transfer coefficient
based on the heat transfer coefficient. The heat transfer
coefficient is calculated using Seider-Tate correlation. In this work air as a binary mixture of Oxygen and Nitrogen has been considered as the working fluid.