Experimental and numerical analysis of solar air heater accoutered with modified conical vortex generators in a staggered fashion

摘要

Introducing flow turbulators in the duct of a solar air heater has proved to be one of the most effective ways to improve the energy utilization efficiency of the device. In the present investigation, solar air heater accoutered with altered conical vortex generators in a staggered arrangement is analysed for different relative pitch ratio (2.67-15) and relative height ratio (0.17-0.34). The performance is evalu-ated for an appropriate range of Reynolds number (3500-1600 0), using the latest computational tool, ANSYS FLUENT 19.2. The numerical results are validated experimentally using a fabricated experimental set up similar to the numerical model. Overall evaluation criteria is employed to achieve an ideal geometrical parameter for the considered range of Reynolds number. Empirical correlations for perfor-mance indices, Nusselt number and friction factor as functions of considered geometrical and operational parameters are developed. Employment of modified conical vortex generators in a staggered arrange-ment resulted in a 257% enhancement in thermal performance. Highest thermohydraulic performance parameter of 2.04 is achieved. (c) 2021 Elsevier Ltd. All rights reserved.