Heat transfer characteristics between clusters of air jet and heated blocks simulating an electronics packaging were studied experimentally. The purpose of this work was to investigate heat transfer coefficients for single-phase jets impinging normally against a isothermally heated block. Air jets were issued from the orifice plate and impinged perpendicularly on the top surface of the blocks. The spent air was discharged to the upper exit in a single direction along the vertical channel formed by the nozzle plate and the plate mounted with the heated blocks. The parameters in this study were average jet Reynolds number (Re), several types of nozzle plate, and nozzle-to-plate spacing (Z/D), and input power (Q).
In the experimental study, attentions were focused on the relations among jet Reynolds number, heat transfer coefficient, the nozzle-to-plate spacing (Z/D) changing the jet Reynolds number and temperature distributions, and Nusselt number varying the nozzle plates. It was found that air impingement input power 23 Watt per chip would satisfy the cooling performance required in the electronic system below commercial operating temperature(75°C).