Study of Convective Laminar Flow in Jets

Abstract

Laminar steady forced convective jet flow is, theoretically, investigated. This is important for cooling of electronic equipment and many other industrial applications. Jets with circular cross-section and with slot cross section are studied.

The two dimensional laminar free and impinging jets are studied. For slot jet, the case of presence of cross flow is also investigated. The target wall is taken as flat plate of constant wall temperature. The two dimensional governing equations of convective flow consist of continuity, momentum and energy equations in cylinderical and cartesian coordinates for the case of circular and slot jet; respectively. The flow is asstm1ed to be steady and laminar with constant properties. Moreover, uniform velocity and temperature profiles at the jet exit are assumed. These flow describing equations are written in din1ensionless form by introducing appropriate dimensionless independent and dependant variables.

The din1ensionless form of governmg equations are sol ved nU111erically using fmite difference technique. According to this technique, the partial differential form of goveming equations are transformed to sets of linear algebraic equations. Since the flow is symmetrical with respect to the jet axis, the solution of the governing equation is canied out for the half of the flow domain, except the case of presence of cross flow.

The systems of algebraic equations are sol ved using Gauss-Siedel iteration method. A computer program in FORTRAN POWER STATION language is developed to perform the numerical solution.