FREE AND CONFINED JETS AT LOW REYNOLDS-NUMBERS

被引：17

作者：

KOLLERMILOJEVIC, D ^{[1
]}

SCHNEIDER, W ^{[1
]}

机构：

[1] TECH UNIV VIENNA,INST STROMUNGSLEHRE & WARMEUBERTRAGUNG,A-1040 VIENNA,AUSTRIA

来源：

FLUID DYNAMICS RESEARCH | 1993年 / 12卷 / 06期

基金：

美国国家科学基金会;

关键词：

D O I：

10.1016/0169-5983(93)90033-7

中图分类号：

O3 [力学];

学科分类号：

08 ; 0801 ;

摘要：

Free jets, and jets with tubular confinements, are investigated in the jet Reynolds number regime 80 less than or equal to Re-i less than or equal to 1000 being of interest for micro-jet pumps, among other applications. For issuing the jets, conventional (single-hole) nozzles as well as dual-hole nozzles of a particular design are used. Both flow visualization and LDA measurement indicate that, in agreement with previous findings, the jets issuing from conventional nozzles remain laminar up to large distances from the orifice. Thus there is but little entrainment of ambient fluid, and the performance of conventional nozzles in micro-jet pumps is rather poor. The dual-hole nozzles, on the other hand, are found to enforce transition to turbulent how near the orifices. As a result, the entrainment rate is considerably increased, and the performance of jet pumps is improved when the dual-hole nozzles are applied. The experimental data are found to be in fair agreement with predictions based on mass and momentum balances.

引用

页码：307 / 322

页数：16

共 21 条

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