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Show 1. INTRODUCTION Preliminary tests of a novel atomization technique for coal water slurry (CWS) using a pulse combustor to atomize the fuel have been carried out successfully. There are several motivating factors for such studies. These include the desire for a simplified method of atomizing liquids, and the improvement in efficiency of power production available by the elimination of a boost compressor in the system, as well as the possibility of improved atomization quality. The primary application envisioned is for use in coal fired gas turbine systems, but other applications include CWS fired boilers and spray drying. The basic concept of pulse atomization is to use a hot pulsating flow from a pulse combustor to accomplish the atomization of a feed stream of CWS, as is shown schematically in Fig. 1. This flow, with its rapid velocity and pressure fluctuations, should provide excellent atomization. Past work related to this concept includes a pulse combustion aerosol generator to disperse insecticide developed by Tenney et al [1]. Lockwood [2] points out that valveless pulse combustors can atomize viscous slurries very effectively, while providing the added benefit of driving off the carrier liquid. These advantages have led to successful commercialization of pulse combustion drying systems for food processing and other applications [3]. In a related concept, Swamyet al [4] have shown that an "acoustic" nozzle can improve the atomization and combustion of heavy fuel oils. Figure 2 shows schematically the improvement in cycle efficiency which can be achieved in a coal fired gas turbine system. The illustration is carried out for an ideal Brayton cycle fired on CWS, so it illustrates a conservative estimate of the possible improvement. Using compressors |