Primary breakup of shear thickening suspension jet by an annular air jet

Abstract This paper deals with an experimental investigation of a novel and simple reverse flow combustor, operated stably with a liquid fuel (ethanol) for heat release intensities ranging from 16 to 25 MW/(m3·atm) with very low NOx and CO emissions. The liquid fuel is injected coaxially with the air jet along the centerline of the combustor. The high velocity air annulus helps in primary breakup of the liquid fuel jet. Air injection along the combustor centerline results in a strong peripheral vortex inside the combustor leading to enhanced product gas recirculation, internal preheating of the reactants, and stabilization of reaction zones. Single-digit NOx emissions were obtained for both coaxial fuel injection (non-premixed) and a premixed–prevaporized (PP) cases for all operating conditions. CO emissions for both the modes were less than 100 ppm (ϕ < 0.75). CH* chemiluminescence images revealed two distinct flame structures for coaxial fuel injection case. A single flame structure for PP case was observed extending from the injector exit to the bottom of the combustor. The instantaneous (spatially averaged) CH* intensity fluctuations were significantly lower for the PP case as compared to the coaxial fuel injection case.

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Significance of Buoyancy, Velocity Index and Thickness of an Upper Horizontal Surface of a Paraboloid of Revolution: The Case of Non-Newtonian Carreau Fluid

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.387.550 ◽

2018 ◽

Vol 387 ◽

pp. 550-561 ◽

Cited By ~ 9

Author(s):

Oluwole Daniel Makinde ◽

M.T. Omojola ◽

B. Mahanthesh ◽

F.I. Alao ◽

K.S. Adegbie ◽

...

Keyword(s):

Fluid Flow ◽

Chemical Engineering ◽

Shear Thickening ◽

Deborah Number ◽

Horizontal Surface ◽

Carreau Fluid ◽

Local Skin ◽

Air Jet ◽

Paraboloid Of Revolution ◽

Thickness Parameter

The problem of fluid flow on air-jet weaving machine (i.e. mechanical engineering and chemical engineering) is deliberated upon in this report using the case of non-Newtonian Carreau fluid flow. In this report, the boundary layer flow of the fluid over an upper horizontal surface of a paraboloid of revolution is presented. The dimensional governing equations were non-dimensionalized, parameterized, solved numerically and discussed. Maximum horizontal velocity is ascertained at smaller values of thickness parameter, a larger value of buoyancy related parameter and the flow is characterized as shear-thickening. Local skin friction coefficient is an increasing and a decreasing property of Deborah number for Shear thinning and Shear-thickening cases of the flow respectively. The velocity of the flow parallel to the surface (uhspr) is a decreasing property of thickness parameter and increasing function of velocity index parameter.

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