โ Scribed by H.B. Awbi; A. Hatton
No coin nor oath required. For personal study only.
In most building thermal load calculations natural convective heat transfer is assumed for internal room surfaces. When mechanical ลฝ . ventilation is used, the natural convective heat transfer coefficient CHTC will underestimate the convective heat transfer from the room surface. In this paper, measured local and surface-mean convective heat transfer data are presented for convection from a heated surface partially covered by an air jet. Experiments were conducted in a small office-sized, well-insulated environmental chamber with heating plates fixed to the internal surfaces. A fan box with an adjustable nozzle was placed at one end of the surfaces within the chamber to create the convective flow. Cooling was provided at one wall to represent a heat sink. Equations are presented for predicting mixed convection heat transfer as a combination of natural and forced convection for walls, floor and ceiling. When the jet acted on a heated surface the measured CHTC was greater than the equivalent natural convection CHTC, although the increase for the ceiling was much greater than for the floor or wall.
๐ SIMILAR VOLUMES