Numerical study of Fluid Flow and Heat Transfer Characteristics due to Air Jet Impingement in Food Cooling Process

Abstract

When the temperature of the impinging fluid differs from that of the impingement surface, impingement cooling is extensively used to achieve high heat transfer rates. The surface heat transfer coefficient in impact cooling depends on several impact parameters, namely the design of the nozzle, the geometry of the object to be cooled, the exit distance of the beam from the object body, jet speed, and jet limit. Jet impingement is frequently used in a number of industrial settings to achieve high local heat transfer coefficients. This present work is about the air impingement cooling of hemispherical foodstuff, and it was done using ANSYS Fluent and computational fluid dynamics (CFD). As a Turbulence model, SST k-ω was employed. Several fluid flow regions were presented. Local Nusselt number distributions over the heated object's surface were studied for different Reynolds numbers (23,000–100,000), jet-to-cylinder distances (2–8), and surface curvature (0.57–1.14). The Nusselt number of stagnations increases as the Reynolds number increases, but reduces as the surface curvature increases and h/d has very little significance.