Buoyancy eects on heat transfer and temperature pro®les in horizontal pipe ̄ow of drag-reducing ̄uids
نویسندگان
چکیده
We have studied the extent to which buoyancy eects in horizontal pipe ̄ows of drag-reducing viscoelastic ̄uids cause distortions to both laminar and turbulent temperature pro®les. In the case of laminar ̄ows, these distortions may lead to variations in Nusselt numbers that are larger than those seen for Newtonian pipe ̄ows under similar conditions. In the case of turbulent drag-reducing ̄ows, the eects of buoyancy can also be large and may in turn result in large errors in estimated Nusselt numbers if not properly accounted for. These errors are quanti®ed and recommendations are made on how to reduce them. 7 2000 Elsevier Science Ltd. All rights reserved.
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