Share

The effects of micro-structured surfaces on multi-nozzle spray cooling.

Author(s) : HOU Y., TAO Y., HUAI X.

Type of article: Article

Summary

Experiments were conducted to investigate heat transfer characteristics of spray cooling with eight nozzles for micro-structured surfaces included cubic pin fins and straight pin fins of different sizes. Liquid volume flow rate ranged from 2.46 × 10-2 m3/s/m2 to 3.91 × 10-2 m3/s/m2 and the corresponded inlet pressures changed from 0.28 MPa to 0.6 MPa by keeping the inlet water temperature between 20.4°C and 24.31°C. And the input power of heat block varied from 180 W to 1080 W. The results show that the heat transfer performances of straight fins2 and straight fins3 are the best in single phase zone, but the cubic pin fins is better in two phase zone. Notably, the critical point between single phase zone and two phase zone shifts to left with the increasing of liquid volume flow rate. Moreover, with the liquid volume flow rate increasing, the heat transfer coefficient increases as well, but straight fins1 and polished surface are not sensitive to this change. For a deeper analysis of the heat transfer enhancement, a dimensionless number (DM) is created to characterize heat transfer performance of different microstructures in single phase heat transfer. We verified the dimensionless number using experimental results in this study and previous literature. Furthermore, the micro-structured surfaces have negligible effects on temperature distribution except for cubic pin fins.

Details


Links


See other articles in this issue (15)
See the source

Indexing