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Two sub‐bituminous coals, a bituminous coal and a reject coal of 55% ash were gasified with steam and air in a 0.31‐m dia. reactor operated in the fluidized and spouted bed modes. Inert beds of 1.1 mm dia. Ottawa sand and 2.1 mm dia. gravel provided stable fluidization and spouting respectively, at superficial velocities in the range 1.3–1.6 m/s. Coals of 1.19–3.36 mm diameter were fed to the gasifier at rates up to 45 kg/h and a range of air/coal ratios. For a given coal, results in the two systems were basically similar, although differences in gas heating value, gas yield and thermal efficiency were noted for some coals.

of the Strouhal number." Morrow and Kline (1971) obtained the following correlation for the Strouhal number, St, for circular cylinders in flow of water St = 0.187 -4.15/Re (50 < Re < 150) which is 7-9% below Roshko's correlation measured in air St = 0.212 -4.5/Re (50 < Re < 150)where both St and the Reynolds number, Re, are based on the cylinder diameter (Roshko, 1953). Klemp and Acrivos (1971) made a flow visualization study of vortex shedding from circular cylinders using air bubbles in oil. Morrow and Kline have noted that there is better agreement between correlations for water and oil than for either liquid with the air correlations of Roshko (1953) or the more recent one of Tritton (1959). Thus, there is a yet unclear distinction between the Strouhal number in liquids and that in air. Unfortunately, these studies ivere not being extended to higher Reynolds numbers to check if the asymptotic value of St = 0.21 for Re > 500 is the same for both air and liquids. The data of Liu, et al. (1970), indicate a lower St in water flow for Re ~7000. To the authors' knowledge there has not been a systematic study of the influence of stream turbulence on the Strouhal number of blunt bodies in liquid flow.