Pitot pressure measurements in a supersonic steam jet

Al-Doori, Ghassan and Buttsworth, David R. (2014) Pitot pressure measurements in a supersonic steam jet. Experimental Thermal and Fluid Science, 58. pp. 56-61. ISSN 0894-1777

Abstract

Ejectors produce a pumping effect based on high speed jet entrainment but data on the development of mixing in steam ejectors with condensation effects is not available. In the present work, the mixing region generated downstream of an axisymmetric supersonic steam ejector nozzle is surveyed using a pitot pressure probe. Steam was delivered to the nozzle at a stagnation temperature of 142°C and at a stagnation pressure of either 270 or 300kPa. The nozzle had an exit diameter of 13.6mm and it produced a flow of steam at approximately 1150m/s, resulting in high compressibility mixing conditions; the convective Mach number was approximately 1.5. Pitot pressure profiles at positions 1, 25, 50, and 70mm downstream of the nozzle exit were obtained within a steam vapour-filled test section at a pressure of approximately 3kPa. The data demonstrates that the jet was slightly over-expanded at these conditions with non-uniformities in the pitot pressure data apparent at the 25mm station. The free shear layer growth rate deduced from the pitot pressure measurements was δ ' ≈ 0.06 ± 0.02 and this value agrees with established empirical results for compressible, planar mixing layers. There are reasonable prospects for the development of reliable engineering models for secondary stream entrainment in ejector applications based on existing correlations for compressible mixing.


Statistics for USQ ePrint 26549
Statistics for this ePrint Item
Item Type: Article (Commonwealth Reporting Category C)
Refereed: Yes
Item Status: Live Archive
Additional Information: © 2014 Elsevier Inc. Permanent restricted access to published version due to publisher copyright policy.
Faculty / Department / School: Current - Faculty of Health, Engineering and Sciences - School of Mechanical and Electrical Engineering
Date Deposited: 14 Jan 2015 04:51
Last Modified: 07 Jul 2016 06:02
Uncontrolled Keywords: mixing; pitot pressure; steam jet
Fields of Research : 09 Engineering > 0904 Chemical Engineering > 090405 Non-automotive Combustion and Fuel Engineering (incl. Alternative/Renewable Fuels)
09 Engineering > 0901 Aerospace Engineering > 090104 Aircraft Performance and Flight Control Systems
09 Engineering > 0901 Aerospace Engineering > 090107 Hypersonic Propulsion and Hypersonic Aerodynamics
Socio-Economic Objective: B Economic Development > 88 Transport > 8803 Aerospace Transport > 880399 Aerospace Transport not elsewhere classified
Identification Number or DOI: 10.1016/j.expthermflusci.2014.05.012
URI: http://eprints.usq.edu.au/id/eprint/26549

Actions (login required)

View Item Archive Repository Staff Only