An experimental investigation of turbulent slot injection at Mach 6

Parthasarathy, K. R.; Zakkay, V.

doi:10.2514/3.5889

Cited by 71 publications

(14 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Among numerous skin friction/ thermal protection techniques [4,5,6], boundary-layer combustion technique, which use a injection and combustion of flammable gas like hydrogen, attracts worldwide attention because of its excellent skin-friction reduction performance.…”

Section: Introductionmentioning

confidence: 99%

Hydrogen Energy paper 17

2018

Proceeding of 2018 the Fourth International Symposium on Hydrogen Energy, Renewable Energy and Materials

View full text Add to dashboard Cite

Abstract:The improvement of the skin friction/heat transfer prediction theory of compressible turbulent boundary-layer combustion of hydrogen is conducted in this paper. The original theory is improved through two aspects. One is the modification of the relation between surface hydrogen mass fraction and Reynolds number by rebuilding the Kármán momentum integral relation. The other is the change of computational method of Prandtl number by adopting the molecular kinetic theory. The improved theory is used to make prediction of skin friction and heat transfer that are found to be better consistent with experimental results than original theory. In addition, a numerical experiment of boundary-layer combustion is conducted. By comparing the results given by numerical simulation and theoretical prediction, it also found that the improved theory shows better prediction performance than the original theory.

show abstract

Section: Introductionmentioning

confidence: 99%

Hydrogen Energy paper 17

2018

Proceeding of 2018 the Fourth International Symposium on Hydrogen Energy, Renewable Energy and Materials

View full text Add to dashboard Cite

show abstract

“…Repukhov [9] also found that the compressibility effects on film cooling performance were very small over a wide range of test conditions. On the contrary, Dellimore et al [10] and Parthasarathy and Zakkay [11] investigated the compressibility effects on film cooling effectiveness, and they concluded that compressibility effects could be significant once the Mach numbers of the flows were high enough. Although those previous studies uncovered useful information, some of the inconsistencies noted raise concerns, and no consensus has been reached yet regarding the effects of flow compressibility on film cooling performance.…”

mentioning

confidence: 99%

Effects of Flow Compressibility and Density Ratio on Film Cooling Performance

Zhou

Johnson

2017

Journal of Propulsion and Power

View full text Add to dashboard Cite

An experimental investigation was performed to examine the effects of flow compressibility and density ratio of coolant to mainstream flows on the performance of film cooling injected from a row of cylindrical holes over a flat plate. The experimental study was conducted in a transonic wind tunnel. A pressure-sensitive paint technique was used to map the corresponding adiabatic film cooling effectiveness distributions over the surface of interest, based on a mass flux analog to traditional temperature-based cooling effectiveness measurements. It was found that, at the relatively low blowing ratio of M ≤ 0.40, the flow compressibility had almost no effects on the film cooling effectiveness over the surface of interest. At relatively high blowing ratios of M ≥ 0.85, the film cooling effectiveness for the test case with compressible, transonic mainstream flow was found to become marginally better than that with the mainstream being incompressible. Although the density ratio was found to have limited effects on the film cooling performance at relatively low blowing ratios, it was found to affect the film cooling effectiveness substantially at relatively high blowing ratios. A denser coolant flow would result in a better film cooling protection to the surface of interest. Nomenclature

show abstract

“…Based on their results, the flowfield of supersonic film cooling can be divided into three regions: potential/core/mixing region, wall-jet region, and boundary-layer region. When the original researches of supersonic film cooling were conducted, the film gas was mainly injected into the supersonic mainstream at sonic speed, including the experiments of Goldstein et al, 8 Parthasarathy and Zakkay, 9 Cary and Hefner, 10 and Richard and Stollery. 11 Later, the supersonic injection of film coolant into supersonic mainstream were becoming the focuses of the researchers, such as the works of Olsen et al, 12 Bass et al, 13 Hunt et al 14 and Juhany et al 15 Olsen et al 12 analyzed the effects of coolant feeding pressure, slot height, and lip thickness on film cooling.…”

Section: Introductionmentioning

confidence: 99%

Numerical simulation of supersonic film cooling in a rearward-facing slot

Chen

Shen

2017

Advances in Mechanical Engineering

View full text Add to dashboard Cite

Supersonic film cooling tangentially ejected through a half Laval nozzle set in a backward-facing slot was numerically simulated to investigate the structures of flowfield and the mechanisms of heat transfer after the slot. In particular, changes in flowfield near the turning point in the cooling effectiveness curve were studied. The turning point is defined by extrapolation of the cooling effectiveness curve using a power-law relationship. The point corresponds to the streamwise position where the hot mainstream is reaching the wall protected by the film coolant and to the disappearance of the unsmooth transition points in streamwise velocity profiles, where the growth rate of velocity in wall normal direction changes gradually from one state to another. The transition of velocity becomes smooth downstream of the turning point. The unsmooth transition point also exists in other profiles of flow parameters, such as the mole fraction of film gas and the total temperature of the fluid, which are indicators of the mixing extent between the mainstream and film coolants. Moreover, the unsmooth transition point is more evident in the film coolant of nitrogen than that of helium due to the slower drop rate of effectiveness in the current configuration of the supersonic film cooling.

show abstract

An experimental investigation of turbulent slot injection at Mach 6

Cited by 71 publications

References 8 publications

Hydrogen Energy paper 17

Hydrogen Energy paper 17

Effects of Flow Compressibility and Density Ratio on Film Cooling Performance

Numerical simulation of supersonic film cooling in a rearward-facing slot

Contact Info

Product

Resources

About