Turbulent heat transfer characteristics and pressure drop in swirling flow at upstream and downstream of an abrupt expansion |
| |
Authors: | A E Zohir |
| |
Institution: | (1) Mechanical Engineering Deparment, Tabbin Institute for Metallurgical Studies, Cairo, Egypt |
| |
Abstract: | This investigation is aimed at studying the heat transfer characteristics and pressure drop for turbulent airflow in a sudden
expansion pipe equipped with propeller swirl generator. The investigation is performed for the Reynolds number ranging from
10,000 to 41,000 under a uniform heat flux condition. The experiments are conducted for three locations for the propeller
fan upstream the sudden expansion and three locations downstream the sudden expansion (N = 5 blades and blade angle of 45°). The influences of using a freely rotating propeller on heat transfer enhancement and
pressure drop are reported. The experimental results indicate that inserting the propeller downstream of the tube provides
considerable improvement of the heat transfer rate higher than inserting the propeller upstream the tube. The increase in
pressure drop resulting from using the propeller upstream is found to be higher than the downstream swirler. The maximum performance
enhancement for the downstream swirler is about 326% while it is about 213% for upstream one. Correlations for relative mean
Nusselt number and enhancement performance are presented for different fan locations and different Reynolds numbers. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|