Recent progress in flame stabilization technologies for combustion-based micro energy and power systems

Experimental investigation on combustion characteristics of premixed propane/air in a micro-planar heat recirculation combustor

Heat recirculating reactors: Fundamental research and applications

Development of a high-temperature and high-uniformity micro planar combustor for thermophotovoltaics application

IN conjunction with Mr. D. L. Hodge, for some time past I have been studying experimentally the combustion of 2CO+O2 (moist and dry) in a steady high tension direct current discharge, and the experiments have resulted in some new observations which seem to have an important bearing upon the function of steam in the combustion of carbonic oxide. We hope soon to communicate a detailed account of them to the Royal Society; meanwhile, in view of the general interest in the subject, we should like to make the following brief statement of the results.

Flame and Combustion

Effects of heat recirculation on combustion characteristics of n-heptane in micro combustors

Experimental study of n-heptane/air combustion in meso-scale burners with porous media

Cold-flow tests, thermal tests, and numerical simulation were performed to study the thrust-adjustment characteristics, and the thrust-vector-control characteristics, of a fluidic nozzle throat com...

Thrust Control by Fluidic Injection in Solid Rocket Motors

Todiscover thrust-oscillation characteristics in solid rocketmotors, analyticalmodeling andnumerical simulation are carried out by an experimentalmotor in the vonKarman Institute for FluidDynamics. The numericalmethod by means of amesh sensitivity analysis is proposed for validation. Velocity profiles, oscillation frequencies, and pressure amplitudes were obtained by numerical simulations and then compared with the experimental data. Various cases with different inlet temperatures are proposed to investigate the influences of parameters on the oscillation characteristics. The results indicate that it is not a necessary condition for vortex-shedding frequency to approach a certain acoustic frequency when periodic oscillations are generated. Oscillations are more severe if the vortexsheddingphenomenon coupleswithhigh-order acousticmodes.Velocitymagnitude in the combustion chamber is the main factor that influences the vortex-shedding frequency; meanwhile, the pressure amplitude is mostly determined by themeanMach number. Theoretical modeling in conjunction with numerical calculations proves that the ratio of dimensionless thrust amplitude to pressure amplitude is predominantly determined by the throat-to-port-area ratio J, and it varies inversely as J. An integrated formula is presented to describe the relationship between thrust amplitude and pressure amplitude.

Theoretical Modeling and Numerical Study for Thrust- Oscillation Characteristics in Solid Rocket Motors

The purpose of this paper is to investigate the combustion process and its change with time due to solid-fuel regression in a solid-fuel scramjet combustor. The combustion process is simplified in the sequence changing of three regression shapes. The solid fuel uses hydroxyl-terminated polybutadiene with a global one-step reaction mechanism. Numerical simulations based on the shear stress transport k-ω model are confirmed by experiments. The simulation data generally agree with the experimental data published in the literature. For simplification, three typical instants during the combustion process, implying three different internal shapes due to fuel regression, are considered. With the sequence of three regression shapes, the fuel diffusion from a solid-fuel surface becomes more extensive and, furthermore, enhances the global combustion efficiency, which is nearly up to 45% at the outlet of the combustor. The simulation results also reveal that the cavity in the combustor provides a fuel enrichment zon...

Zhijun Wei

Papers

Effects of heat recirculation on combustion characteristics of n-heptane in micro combustors

Experimental study of n-heptane/air combustion in meso-scale burners with porous media

Thrust Control by Fluidic Injection in Solid Rocket Motors

Theoretical Modeling and Numerical Study for Thrust- Oscillation Characteristics in Solid Rocket Motors

Numerical Investigation on Internal Regressing Shapes of Solid-Fuel Scramjet Combustor