Published 8 issues per year
ISSN Print: 1065-5131
ISSN Online: 1563-5074
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Experimental Study of Heat Transfer in a Short Slot Duct with High Deflection of Inlet Flow Velocity from the Duct Axis
ABSTRACT
When a heated duct is one of the output ducts in the construction of a distributing header, specific conditions of heat transfer are generated as a result of interaction between the header flow (streaming flow) and the output duct flow. In this work, slot-type ducts were studied. An important feature of the investigation is the use of both a smooth output duct and ducts with heat transfer enhancement reliefs (5 specimens). Thus, interaction between the streaming flow turbulence and self-turbulence in a duct can be studied more carefully. The evolution of the average perimeter heat transfer along the duct is investigated for various situations mentioned. The corresponding results were obtained. If the velocity of the streaming flow is of the same order of magnitude as that of the flowing-out one or higher substantial heat-transfer enhancement is observed for the smooth output duct. When the wide sides of the duct were extended by a special relief, the scale of the streaming flow effect was decreased. The greater the surface extension, the less was the streaming flow effect. On triple enhancement of the duct heat transfer the streaming flow effect practically disappeared.