Entrainment Effects on Impingement Heat Transfer: Part I—Measurements of Heated Jet Velocity and Temperature Distributions and Recovery Temperatures on Target Surface

Abstract

Experiments were conducted to characterize a heated turbulent air jet discharged from a square-edged orifice having length to diameter equal to unity. Reported are measurements of mean axial velocity and total temperature in the jet as well as recovery temperatures on a flat surface normal to the jet axis. A simple theoretical model, which predicts distributions of recovery temperature consistent with the test data, is given.

Asymmetric entrainment effect on the local surface temperature of a flat plate heated by an obliquely impinging two-dimensional jet

“…The centerline velocity V c is decreases substantially after z/D h $ 1.5, following a classical trend of (z/D h ) À1/2 . The axial variation of the centerline velocity along the z-axis suggests that the potential core lies within 2D h , which is typical of two-dimensional orifices [12].…”

Local heat transfer due to several configurations of circular air jets impinging on a flat plate with and without semi-confinement

“…Other researchers used the adiabatic temperature as a reference to calculate heat transfer coefficients. So, in the case of a single jet, Hollworth and Wilson [5] noticed that for H/D 5, profiles of dimensionless adiabatic temperature did not depend on Reynolds number and jet-to-plate spacing. With the same apparatus, Hollworth and Gero [6] concluded that if adiabatic temperature is taken as the reference temperature, Nusselt number values are independent from (T j − T ∞ ).…”

Invisibly at Risk: Low-Income Students in a Middle- and Upper-Class World

“…Results of crossflow on streamwise resolved Nusselt numbers were comparable to that of Chance (1974), kercher andTabakoff (1970). Hollworth and Wilson (1984) [11] conducted experiments to characterize a heated turbulent air jet discharged from a square-edged orifice having length to diameter equal to unity. A theoretical model was developed to show the distributions of recovery temperature with the test data.…”