Objective This project aims at comparing pressurized pulverized coal combustion systems with atmospheric and catalytic pulverized coal combustion systems and with other more advanced combustion technologies. The objective is to assess the viability and technical merits of pressurised pulverised coal combustion. This will be achieved with the aid of a calculation method developed and appraised in relation to measurements obtained by laser-based instrumentation. The calculation method will be based on the numerical solution of three dimensional forms of the Navier-Stokes equations and make use of second-order accurate methodology, including the upwind scheme, together with a version of Stone's algorithm. The numerical procedures have been extended to second-order accuracy and are presently being tested. The turbulence model is based on a form of the two-equation approach involving solutions of the equation for turbulence energy and dissipation rate with allowance for streamline curvature and the scalar-flux equations on a turbulent Prandtl number. Special consideration has been given to the representation of the equations of two-phase flow so that Eulerian and Lagrangian approaches are available and are among the most advanced in the world. Combustion is represented by an assumed form of the probability distribution of the scalar with fast reaction of gaseous fuel. Considerable effort has been devoted to the particular features of solid fuels so that the model includes consideration of devolatilisation and the generation of pollutants. The numerical approach will be improved under the proposed research with the introduction of a solution procedures based on curvi-linear coordinates, the incorporation of third-order accurate numerical assumptions, and further improvements to the solution algorithm, as the employment of the Conjugate Gradient method. The physical models can all be improved and, in advance of the accompanying experiments, consideration will be given to higher-order turbulence models, improvements to the combustion model for solid fuel and to the flux-approach to radiation. The experiments described below will be arranged to aid the development of the calculation method and will guide further improvements. The measurement techniques developed for the measurement of particle size and for the temperature of the mantle of burning fluid around the particle will also be used together with laser velocimetry, digitally-compensated thermocouples and standard procedures for the measurement of emissions. The particle-sizing method is comparatively slow and will be speeded up, possibly through the use of digital signal processors (DSP-based processors), which will be developed for this purpose. In addition, the two-colour pyrometry which leads to the temperature of the burning mantle around the coal particles will be used as a means of separating burning from non-burning particles and, therefore, as an aid to the identification of the trajectory and origin of each particle; it will also be further examined to determine the temperature distribution within the mantle. Developments are also planned whereby laser-based techniques, such as for example laser-induced fluorescence from the OH radical, will be used to measure gas temperature so that vector-scalar correlations will also be possible. This spectrum of measured information will considerably enhance the ability to appraise and develop the calculation method. Fields of science engineering and technologyenvironmental engineeringenergy and fuelsfossil energycoalnatural sciencesphysical sciencesclassical mechanicsfluid mechanicsfluid dynamicssocial scienceseconomics and businessbusiness and managementemploymentnatural sciencesphysical sciencesopticslaser physics Programme(s) FP3-JOULE 2 - Specific research and technological development programme (EEC) in the field of non-nuclear energy, 1990-1994 Topic(s) 0201 - Energy production from fossil sources using advanced technologies Call for proposal Data not available Funding Scheme CSC - Cost-sharing contracts Coordinator NATIONAL TECHNICAL UNIVERSITY OF ATHENS EU contribution No data Address Iroon Polytechnioy 5 15780 ATHENS Greece See on map Total cost No data Participants (1) Sort alphabetically Sort by EU Contribution Expand all Collapse all IMPERIAL COLLEGE OF SCIENCE, TECHNOLOGY AND MEDICINE United Kingdom EU contribution No data Address South Kensington Campus LONDON See on map Total cost No data
