An experimental investigation of thermal mixing and combustion in supersonic flows

Srikrishnan, A R; Kurian, Job; Sriramulu, V.

doi:10.1016/s0010-2180(96)00084-3

Cited by 15 publications

(6 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Large streamwise vorticity generated by such convoluted nozzle structure was shown to have increased the mixing and entrainment rate greatly. They were particularly useful for applications in supersonic ejectors [4,8] and for improvements in supersonic combustion [9]. However, large stagnation pressure loss due to complex shock structure associated with such nozzles was also reported [8].…”

Section: Introductionmentioning

confidence: 99%

Comparative studies on supersonic free jets from nozzles of complex geometry

Rao

Asano

Saito

2016

Applied Thermal Engineering

View full text Add to dashboard Cite

Experimental and numerical studies are conducted to compare free jets from different supersonic nozzles for mixing enhancement. A conical nozzle of Mach 1.80 is the reference. Three complex nozzles are a beveled nozzle, a nozzle with six chevrons and a six lobed ESTS nozzle [1]. All nozzles have the same throat diameter and designed average exit Mach number. The studies are conducted at NPR=6, using acetone PLIF, centerline pitot pressure measurements and 3D RANS simulations. A novel method of decomposing PLIF images based on intensity histogram and then recomposing after applying selective gains to emphasize the growth of shear layers is discussed. PLIF images are processed to extract the growth rate of jet width which indicates the rate of mixing. The ESTS lobed nozzle shows the highest enhancement of mixing (430%) followed by chevron (222%) and the beveled nozzle with a moderate (138%). The numerical simulations are validated and agree well with experimental results. ESTS lobed nozzle is found to produce widespread streamwise vortices compared to clustered vortices of the chevron nozzle. The mechanism of streamwise vorticity production from ESTS nozzle is clarified for the first time in this study.

show abstract

Section: Introductionmentioning

confidence: 99%

Comparative studies on supersonic free jets from nozzles of complex geometry

Rao

Asano

Saito

2016

Applied Thermal Engineering

View full text Add to dashboard Cite

show abstract

“…The performance of a conventional conical nozzle was found to be much inferior to that of the petal nozzle under identical conditions. M Deepu [9] worked on the topic of "Recent Advances in Experimental and Numerical Analysis of Scramjet Combustor Flow Fields", and his findings are -Increase in jet to free stream momentum flux ratio will result in the increase of jet penetration to free stream for all kinds of jets. Injector orientation plays an important role in the strength of the bow shock, with the shocks created by oblique injector being substantially weak compared to transverse injector.…”

Section: Literature Reviewmentioning

confidence: 99%

CFD Analysis of a Hydrogen Fueled Mixture in Scramjet Combustor with a Strut Injector by Using Fluent Software

Pandey¹,

Sivasakthivel²

2011

IJET

View full text Add to dashboard Cite

In this study, k-ε model has been used to examine supersonic flow in a model scramjet combustor. The configuration used is similar to the DLR (German Aerospace Center) scramjet model and it is consists of a one-sided divergent channel with a wedge-shaped flameholder at the base of which hydrogen is injected. Here, we investigate supersonic cold flow with hydrogen injection. For the purpose of validation, the k-ε results are compared with experimental data for temperature at the bottom wall. In addition, qualitative comparisons are also made between predicted and measured shadowgraph images. The k-ε computations are capable of predicting cold flow simulations well and good.

show abstract

“…A similar approach has been followed in several previous studies on mixing enhancement (e.g. [7,9,10]).…”

Section: Introductionmentioning

confidence: 97%

“…The triangular tab was found to be a better mixing promoter compared with the rectangular tab. Srikrishnan et al [9,10] have reported mixing enhancement studies using lobed nozzles in co-flowing supersonic jet streams. Nastase et al [11], Nastase and Meslem [12,13] and El Hassan and Meslem [14] carried out comprehensive flow visualization and PIV measurements on cross-orifice jets, daisy-shaped orifice jets and lobed jets.…”

Section: Introductionmentioning

confidence: 99%

Mixing enhancement using chevron nozzle: studies on free jets and confined jets

et al. 2018

View full text Add to dashboard Cite

This paper reports an experimental study focused on the impact of chevrons (serrations on the trailing edge of the nozzle) on the mixing process of an incompressible jet issuing from a convergent nozzle. The study also explores enhancement of the mixing performance by a novel approach to geometry modification. Profiles of mean velocity were used to characterize the extent of mixing. For a comparative assessment, studies were carried out with a base line circular nozzle, a conventional chevron nozzle and an improvised tabbed chevron nozzle. Flow visualization studies were carried out for jets issuing from chevron nozzles and the results corroborate well with quantitative measurements. The impact of confinement on mixing of jets issuing from chevron nozzles is also studied. The results show that the proposed geometry modification can significantly improve the rate of mixing in the range of Reynolds numbers considered in the study. In confined jets, presence of chevrons was found to accelerate the process of jet breakdown .

show abstract

An experimental investigation of thermal mixing and combustion in supersonic flows

Cited by 15 publications

References 15 publications

Comparative studies on supersonic free jets from nozzles of complex geometry

Comparative studies on supersonic free jets from nozzles of complex geometry

CFD Analysis of a Hydrogen Fueled Mixture in Scramjet Combustor with a Strut Injector by Using Fluent Software

Mixing enhancement using chevron nozzle: studies on free jets and confined jets

Contact Info

Product

Resources

About