Convective heat transfer in an axisymmetric confined jet
Abstract
An axisymmetric confined jet is a jet issued coaxially into a cocurrent stream flowing in a circular duct. When the central jet/cocurrent stream momentum ratio is much less than unity, a recirculating flow appears near the wall at some location after the central jet nozzle. The present paper deals with convective heat transfer in a confined heat, with particular attention to the recirculating flow region. Experimental data are presented and their characteristic features are discussed. Augmentation of heat transfer in and after the recirculating flow region of a confined jet is demonstrated. The Craya-Curtet number is found to be the similitude parameter not only for the flow but also for the convective heat transfer in the confined jet. Empirical formulas are presented for the peak Nusselt number and peak position. It is also suggested that maximum heat transfer can occur in the recirculation flow region. The experiments with the smallest duct revealed an additional size effect that cannot be explained by the variation of the Craya-Curtet number.
- Publication:
-
Studies in Heat Transfer: A Festschrift for E. R. G. Eckert
- Pub Date:
- 1979
- Bibcode:
- 1979stht.book..103K
- Keywords:
-
- Axisymmetric Flow;
- Convective Heat Transfer;
- Ducted Flow;
- Jet Flow;
- Nozzle Flow;
- Flow Distribution;
- Nusselt Number;
- Size (Dimensions);
- Test Equipment;
- Wall Flow;
- Fluid Mechanics and Heat Transfer