A feedback control strategy is applied to enhance the performance of a laboratory-scale pulsed combustor operating near the lower flammability limit. As with many combustion processes, at lean conditions, combustion instabilities develop which result in complex, lowfrequency fluctuations in fuel concentration and lead directly to misfire and flameout. The control strategy exploits the highly no...

The goal of this study was twofold. First, modelling strategies were proposed to characterize the dynamics driving the thermoacoustic instabilities in a swirl-stabilized premixed burner. Secondly, this model was used to synthesize controllers in order to apply active control strategies to suppress this phenomenon. An experimental combustor model based on acoustic properties of the combustion ch...

We have developed a new modeling capability to study the behavior of pulse combustors. Our approach is based on the use of higher-order Godunov methods combined with adaptive strategies to focus computational eeort where it is required and a Cartesian grid formulation for modeling realistic engineering geome-tries. The model computes quasi-one-dimensional, axisymmetric, and fully three-dimensio...

An estimation of the conversion efficiency (e) of fuel sulfur to SO3 and H2SO4, where e=([SO3]+[H2SO4])/[ST] and [ST] is the total sulfur atom concentration in the exhaust at the exit of an aircraft gas-turbine combustor, was derived from measurements by comparison with model results. The major results of the presented CIMS experiments and their interpretation with a model simulation are: (i) T...

prove the dissolution property and oral bioavailability of poorly water-soluble drugs, solid dispersion methods have been extensively used and numerous approaches have been reported such as fusion, solvent evaporation, and spray-drying methods. However, these methods involve various problems. Solid dispersions prepared by fusion usually have the shortcoming of being tacky and unstable, and solv...

Since a large number of physical parameters influence the flame dynamics in a full scale gas turbine combustor, it is virtually impossible to develop physically correlated reduced order models for flame dynamics by directly studying these complex reacting flows. Even the Rijke tube combustor system, though comprising of a simple geometry and a flat flame, shows a strong nonlinear coupling betwe...

Contributions from the combustor to the overall propulsion noise of civilian transport aircraft are starting to become important due to turbofan design trends and expected advances in mitigation of other noise sources. During on-ground, static-engine acoustic tests, combustor noise is generally sub-dominant to other engine noise sources because of the absence of in-flight effects. Consequently,...

The modern gas turbine engine requires innovative cooling techniques to protect its internal components from the harsh operating environment typically seen downstream of the combustor. Much research has been performed on the design of these cooling techniques thus allowing for combustion temperatures higher than the melting point of the parts within the turbine. As turbine inlet temperatures an...

Improving the performance and durability of gas turbine aircraft engines depends highly on achieving a better understanding of the flow interactions between the combustor and turbine sections. The flow exiting the combustor is very complex and it is characterized primarily by elevated turbulence and large variations in temperature and pressure. The heat transfer and aerodynamic losses that occu...

An approach to mesoscale electric power production is presented which relies on a clean and efficient combustor coupled with a free-piston Stirling engine. The design and development of a catalytic combustor is discussed, whose main components are: a multiplexed electrospray to disperse jet propulsion fuel (JP-8), a stack of catalytically coated grids through which fuel conversion and heat rele...