Combustion noise from turbofan engines has become important, as the noise from sources like the fan and jet are reduced. An aligned and un-aligned coherence technique has been developed to determine a threshold level for the coherence and thereby help to separate the coherent combustion noise source from other noise sources measured with far-field microphones. This method is compared with a sta...

A technique for measurement of the stable isotope composition of dissolved organic carbon (DOC) in stream water, using an elemental analyzer (EA) coupled to an isotope ratio mass spectrometer (IRMS), is described. Stream water samples were concentrated by rotary evaporation, acidified to remove dissolved inorganic carbon (DIC), and dried in silver cups prior to analysis. Precision was evaluated...

A novel numerical method has been developed to couple a recent high order accurate fully compressible upwind method with the Conditional Moment Closure combustion model. The governing equations, turbulence modelling and numerical methods are presented in full. The new numerical method is validated against Direct Numerical Simulation (DNS) data for a lean premixed methane slot burner. Although t...

Catalytic combustion is an environmentally benign technology which has recently reached the stage of commercialization. Palladium is the catalyst of choice when considering gas turbines fuelled with natural gas because of its superior activity for methane oxidation. Several fundamental issues are still open and their understanding would result in an improvement of the technology. Hence, the wor...

A discontinuous Galerkin algorithm for the simulation of realistic detonation and supersonic combustion systems is developed. This algorithm enables to consider complex and temperature/mixture-dependent thermodynamic transport properties, detailed and stiff reaction chemistry, and the robust shock-capturing. In order to evaluate all relevant algorithmic aspects, the DG-method is applied to a se...

The transport element method is described and implemented in the simulation of the non-premixed reacting shear layer. The method, a natural extention of the vortex element method, resolves the low Mach number variable density ow and the exothermic reacting eld. The eeect of combustion on the ow is accommodated by incorporating a volumetric expansion velocity component and by modifying the integ...

(Abstract • j Turbulent combustion is ubiquitously used in practical combustion devices. However, even chemically non-reacting turbulent flows are complex phenomena, and chemical reactions make the problem even more complicated. Due to the limitation of the computational costs, conventional numerical methods are impractical in carrying out direct 3D numerical simulations at high Reynolds number...

New high order implicit-explicit Runge-Kutta methods have been developed and implemented into a finite volume code to solve the Navier-Stokes equations for reacting gas mixtures. The resulting nonlinear systems in each stage are solved by Newton’s method. If only the chemistry is treated implicitly, the linear systems in each Newton iteration are simple and solved directly. If in addition certa...

Transported probability density function (PDF) methods are used to account for turbulent fluctuations in composition and temperature in simulations of liquid fuel injection (n-heptane), vaporization, mixing, autoignition, combustion and soot formation for a constant-volume combustion chamber. Both stochastic Lagrangian particle and stochastic Eulerian field methods are used to solve the modeled...