Abstract:

                     Objective-This study presents the numerical computation on laminar convection heat transfer in a rectangular channel with Longitudinal Vortex Generator. The use of longitudinal vortex generators in the form of wings and winglets to enhance the heat transfer in the plate heat exchangers is well known. The present study evaluates the potential of a single rectangular winglet and a rectangular winglet pair for heat transfer enhancement in a rectangular channel flow. By providing an obstacle in the form of a single rectangular winglet or rectangular winglet pair which obstructs the primary flow a difference in pressure between the front side and back side is created. This pressure difference drives a secondary flow in a plane transverse to the primary flow. This has the effect of churning the main flow and thus leads to a higher heat transfer rate.

Design / Methodology/ Approach- The comparison of a rectangular channel mounted with single rectangular winglet, a winglet pair and plain rectangular channel at Re=200 is done. The performance of the design is evaluated for a rectangular winglet pair with varying height and in the Reynolds number range of 200 to 500 for an angle of attack β = 28.7º. The level of heat transfer augmentation is quantified in terms of the Nusselt number and the bulk temperature. The fundamental governing equations for incompressible three dimensional laminar flow are considered and Modified MAC Algorithm is used to obtain the numerical solution of the governing equations. While the vortex generator creates a secondary flow it does add to the resistance to the primary flow i.e., a price is to be paid for the heat transfer enhancement in the form of a higher pumping power required to force the fluid across the vortex generator.

Findings- This is evaluated to ensure that the increase in pumping power is moderate. The purpose of heat transfer enhancement techniques is to reduce the size of the heat exchanger for a given heat transfer load. The channel with a winglet pair is more effective as comparison to the single winglet. The heat transfer increases with the increase of the winglet height. The heat transfer increases with the increase in Reynolds number

Scope for further work-The computation has been done assuming the flow regime to be laminar in plate heat exchangers. But in some special application involving high velocity of fluid, the flow regime can become turbulent. Therefore, the present study can be extended for the turbulent flows. Using an appropriate turbulence model, the performance of the purposed design can be computed for high Reynolds number. This study can also be extended for the finite thickness of the winglet pair.

Originality/Value- The paper includes practical examples of organizations following different Professor Strategies and also includes literature review about leadership and talent management, which promotes unique and interesting contributions in research.

Keywords: Numerical Computation , Laminar Convection,  Heat Transfer,  Winglet