Phase-Change Cooling for Operational (Weapons)

"Spray cooling is a very effective convective heat transfer method. Although it is known that spray cooling performance is highly fluid dependent, and decays rapidly with increasing surface area, the relationships still are not well understood.Perversely, the most precipitous decline in cooling capability seems to occur in the region of the most commercial, long-term interest: digital electronic devices in ranging from a few to several millimeters in size. Moving out to larger areas of currentDoD interest, such as laser combiners of several centimeters per side, the further reduction in cooling performance would appear to be comparatively minor. The ability to investigate these relationships for a variety of cooling requirements, with aminimum of experimentation for each special case, would be of great value. The proposed effort will result in a software utility with which to determine the optimum fluid, surface characteristics and operating parameters required for spray cooling of veryhigh heat fluxes over small to large surface areas. Out of emerging necessity, spray cooling is rapidly gaining the attention of electronics OEMs. Electronic systems in the near future will contain many different components, such as power devices,microprocessors, graphics processors and even memory that will require advanced cooling techniques in varying degrees. The ability to quickly predict accurate detailed operating parameters, fluid choice