Abstract
An experimental investigation is conducted to bring out the effects of coolant injector configuration on film cooling effectiveness, film cooled length and film uniformity associated with gaseous and liquid coolants. A series of measurements are performed using hot air as the core gas and gaseous nitrogen and water as the film coolants in a cylindrical test section simulating a thrust chamber. Straight and compound angle injection at two different configurations of 30°–10° and 45°–10° are investigated for the gaseous coolant. Tangential injection at 30° and compound angle injection at 30°–10° are examined for the liquid coolant. The analysis is based on measurements of the film-cooling effectiveness and film uniformity downstream of the injection location at different blowing ratios. Measured results showed that compound angle configuration leads to lower far-field effectiveness and shorter film length compared to tangential injection in the case of liquid film cooling. For similar injector configurations, effectiveness along the stream wise direction showed flat characteristics initially for the liquid coolant, while it was continuously dropping for the gaseous coolant. For liquid coolant, deviations in temperature around the circumference are very low near the injection point, but increases to higher values for regions away from the coolant injection locations. The study brings out the existance of an optimum gaseous film coolant injector configuration for which the effectiveness is maximum.
Similar content being viewed by others
Abbreviations
- D:
-
Pipe diameter (m)
- I:
-
Momentum flux ratio between the coolant and mainstream
- M:
-
Blowing ratio
- Pinj :
-
Coolant injection pressure (bar)
- Tg :
-
Core gas temperature (K)
- x:
-
Axial distance from the coolant injection point (m)
- α:
-
Azimuthal injection angle (°)
- β:
-
Tangential injection angle (°)
- \( \bar{\eta } \) :
-
Circumferentially averaged effectiveness
- \( \bar{\bar{\eta }} \) :
-
Spatially averaged effectiveness
References
Goldstein RJ, Rask RB, Eckert ERG (1966) Film cooling with helium injection into an incompressible air flow. Int J Heat Mass Transf 9:1341–1350
Ligrani PM, Wigle J, Ciriello S, Jackson SW (1994) Film cooling from holes with compound angle orientations: Part 1. Results downstream of two staggered rows of holes with 3d span wise spacing. ASME J Heat Transf 116:341–352
Sen B, Schmidt DL, Bogard DG (1996) Film cooling with compound angle holes: heat transfer. ASME J. Turbomech 118:801–807
Schmidt DL, Sen B, Bogard DG (1996) Film cooling with compound angle holes: adiabatic effectiveness. ASME J Turbomech 118:807–813
Ekkad SV, Zapata D, Han JC (1997) Heat transfer coefficients over a flat surface with air and CO2 injection through compound angle holes using transient liquid crystal image method. ASME J. Turbomech 119:580–587
Lee HW, Park JJ, Lee JS (2002) Flow visualization and film cooling effectiveness measurements around shaped holes with compound angle orientations. Int J Heat Mass Transf 45:142–156
McGrath EL, Leylek JH (1998) Physics of hot flow ingestion in film cooling. ASME Paper No. 98-GT-191
Baheri S, Tabrizi SPA, Jubran BA (2008) Film cooling effectiveness from trenched shaped and compound holes. Heat Mass Transf 44:989–998
Nasir H, Srinath SV, Acharya S (2001) Effect of compound angle injection on flat surface film cooling with large stream wise injection angle. Exp Therm Fluid Sci 25:23–29
Cho HH, Rhee DH, Kim BG (1999) Film cooling effectiveness and heat/mass transfer coefficient measurement around a conical-shaped hole with a compound angle injection. ASME Paper No. 99-GT-38
Bell CM, Hamakawa H, Ligrani PM (2000) Film cooling from shaped holes. ASME J Heat Transf 122:224–232
Brittingham RA, Leylek JH (2000) A detailed analysis of film cooling physics: Part iv-compound-angle injection with shaped holes. ASME J Turbomach 122:133–145
Maiteh BY, Jubran B (1999) Effect of compound angle injection on flat surface film cooling with large stream wise injection angle. Int J Heat Fluid flow 20:158–165
Jubran BA, Al-Hamadi AK, Theodoridis G (1997) Film cooling and heat transfer with air injection through two sets of compound angle holes. Heat Mass Transf 33:93–100
Dittmar J, Schulz A, Wittig S (2003) Assessment of various film-cooling configurations including shaped and compound angle holes based on large-scale experiments. ASME J Turbomach 125:57–64
Taslim ME, Khanicheh A (2005) Film effectiveness downstream of a row of compound angle film holes. ASME J Heat Transf 127:434–440
Hung M, Ding P, Chen P (2009) Effects of injection angle orientation on concave and convex surfaces film cooling. Exp Therm Fluid Sci 33:292–305
Michel B, Gajan P, Strzelecki A, Savary N, Kourta A, Boisson H (2009) Full coverage film cooling using compound angle. C R Mecanique 337:562–572
Sivrioglu M (1991) An analysis of the effects of pressure gradient and streamline curvature on film cooling effectiveness. Heat Mass Transf 26:103–107
Boden RH (1951) Heat transfer in rocket motors and application of film and sweat cooling. ASME Trans 73:385–390
Welsh JWE (1961) Review of results of an early rocket engine film-cooling investigation at the Jet Propulsion laboratory. Technical Report TM-32-58, Jet Propusion Center, California Institute of Technology
Morrell G (1951) Investigation of internal film cooling of a 1000-pound thrust liquid ammonia liquid oxygen rocket. Technical Report, NACA RME51E04
Kinney GR, Abramson AE, Sloop JL (1952) Internal film cooling experiments with 2 and 4 inch smooth surface tubes and gas temperatures to 2000- F in 2 and 4 inch diameter horizontal tubes. Technical Report, NACA report 1087
Abramson AE (1952) Investigation of internal film cooling of exhaust nozzle of a 1000-pound thrust liquid ammonia-liquid oxygen rocket. Technical Report, NACA RME52C26
Knuth EL (1954) The mechanism of film cooling. Dissertation, California Institute of Technology
Warner CF, Emmons DL (1964) Effects of selected gas stream parameters and coolant properties on liquid film cooling. Trans ASME J Heat Transf 1:271–278
Stechman RC, Oberstone J, Howell JC (1969) Design criteria for film cooling for small liquid-propellant rocket engines. J Spacecr Rockets 6:97–102
Kesselring RC, Knight RM, McFarland BL, Gurnitz RN (1972) Boundary cooled rocket engines for space storable proplellants. Technical Report, Rocketdyne Report No. R-8766
Moffat RJ (1985) Describing the uncertainties in experimental results. Exp Therm Fluid Sci 1:3–17
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Shine, S.R., Sunil Kumar, S. & Suresh, B.N. Influence of coolant injector configuration on film cooling effectiveness for gaseous and liquid film coolants. Heat Mass Transfer 48, 849–861 (2012). https://doi.org/10.1007/s00231-011-0936-z
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00231-011-0936-z