Investigation of single phase and boiling jet impingement heat transfer

The need for high-heat flux convective cooling of electronic components has generated considerable research efforts toward the development of enhanced cooling schemes. One scheme that shows a potential for meeting these requirements is jet impingement cooling. Heat transfer coefficients for systems of this type can exceed 1 W/cm;Cooling by jet impingement has been a subject of sustained empirical and numerical research for decades. Although many fluids have been investigated, there is a need for further research with other candidate fluids because the performance is dependent not only on the jet characteristics, but the fluid-surface characteristics as well.;The first objective of this effort was to determine the single phase and boiling jet impingement heat transfer characteristics of Freon 22 using a conventional guarded test section. These data were successfully compared to those obtained using a wafer scale integrated test section made at Alabama Microelectronics Science and Technology Center, Auburn University.;Comparing the results of this research with past literature led to identification of six major findings: (a) A guarded isothermal heat transfer surface with a maximum heat loss of less than 5% in single phase jet impingement and less than 3% when boiling occurs at the face was developed and used. (b) In single phase jet impingement for the jet diameters of 0.5 to 2 mm, the average Nusselt number has a higher dependence on Reynolds number than has been reported by other investigators. (c) The fully developed nucleate boiling curve for Freon 22 is independent of velocity and jet diameter for single and multiple jets. A best line fit (power curve) for the data was also developed that is valid for wall superheats from 6 to 20...