Heat transfer from arrays of impinging jets with large jettojet spacing
Abstract
Local and average convective heat transfer coefficients were measured for arrays of widely spaced impinging air jets and correlated in terms of system geometry, air flow, and fluid properties. The configurations were square arrays of circular turbulent jets (spaced from 1025 diameters apart) incident upon a flat isothermal target surface. Independent parameters were varied over ranges generally corresponding to gas turbine cooling applications. Local heat transfer coefficients were influenced by interference from neighboring jets only when the target plate and the jet orifice plate were less than five jet diameters apart. Average heat transfer coefficients were nearly equal for all the arrays tested as long as the coolant flow per unit area of target surface was held constant. In fact, there was a tendency for the more widely spaced configurations to produce slightly higher average heat transfer under such conditions.
 Publication:

ASME Journal of Heat Transfer
 Pub Date:
 May 1978
 Bibcode:
 1978ATJHT.100..352H
 Keywords:

 Air Cooling;
 Convective Heat Transfer;
 Heat Transfer Coefficients;
 Jet Impingement;
 Turbulent Jets;
 Arrays;
 Gas Turbines;
 Spacing;
 Surface Temperature;
 Temperature Distribution;
 Fluid Mechanics and Heat Transfer