Experimental study of heat transfer enhancement of inserted LED lamp by the closed-cell aluminum-foam ceiling

This work systematically studied the heat transfer characteristics of the porous green building materials. The base materials of these porous green building materials were closed-cell aluminum foams. When the LED lamp is inserted into this porous material, the porous materials may enhance the heat transfer capacity of the heat sink of LED lamp due to their high thermal conductivity. Total four kinds of test heat sinks were employed: (1) Model A—the copper-alloy powder and composite-graphite heat sink with the annular aluminum-alloy conductive base; (2) Model B—the aluminum-alloy powder and composite-graphite heat sink with the annular aluminum-alloy conductive base; (3) Model C—the composite-graphite heat sink with the annular aluminum-alloy conductive base and copper-foam fins; and (4) Model D—the aluminum-alloy heat sink of the Philips LED lamp (Model no.: MASTER LED PAR38 MV). The results showed that the height of the present ceiling's upper space was not the sensitive parameter for heat transfer. Therefore, lower ceiling's upper space is suitable for installing. Among various heat sinks, Model D heat sink had the lowest total thermal resistance. The thermal resistance of the Model D heat sink inserting into the closed-cell aluminum-foam ceiling was only about 0.34 times of that inserting into the wooden ceiling. The other three heat sinks had the similar thermal resistances. The thermal resistances of those three heat sinks inserting into the closed-cell aluminum-foam ceiling were only about 0.33–0.39 times of those inserting into the wooden ceiling. This work demonstrates that the closed-cell aluminum-foam ceiling did help in the cooling of LED lamp.