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The laminar boundary layer on a moving continuous flat surface with suction and injection is investigated for cases where the nonzero transverse velocity profile at the surface is such that similar solutions may be obtained. Under these conditions the thermal and concentration boundary layers are investigated for the case of constant temperature and concentration at the flat surface. Numerical solutions of the boundary layer momentum, energy, and diffusion differential equations are presented for a wide range of the injection parameter, f(0), at Prandtl and Schmidt numbers of 1, 10, and 100. Equations for the Nusselt and Sherwood numbers, and the dimensionless heat and mass transfer coefficients are derived. An asymptotic

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Solidsmixing or solids blending is the operation by which two or more solid materials in particulate form are scattered randomly in a mixer among each other by the random movement of the particles. It has long been one of the most widely used industrial, agricultural, and pharmaceutical processes. However, it has been much less developed both theoretically and practically compared to other processes. Therefore, the practice of art often dominates in the operation and design of the mixing equipment and in the assessment of quality of a mixture. The rapid growth of other process industries has made solids mixing a well recognizedbut not yet well developed operation. A considerable amount

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Liquid dispersion in the radial direction was investigated in the riser of a viscous liquid-solid fluidized bed 0.102 m in diameter and 3.5 m in height. Pressure fluctuations in the riser were also measured and analyzed to examine the behavior of fluidized particles. Effects of liquid velocity (0.15-0.45 m=s), solid circulation rate (2-8 kg=m 2 s), particle size (1-3 mm), and liquid viscosity (0.96-38 mPas) on pressure fluctuations and the liquid radial dispersion coefficient were determined. The infinite space model was employed to obtain the radial dispersion coefficient from the radial concentration profiles of the tracer. The pressure fluctuations were analyzed by means of autocorrelation coefficient as well as power spectral density function. The dominant frequency obtained from the autocorrelation coefficient or power spectral density function of pressure fluctuations decreases with increasing liquid viscosity or liquid velocity, but it increases with increasing particle size. The liquid radial dispersion coefficient decreases with increasing liquid velocity or viscosity, but it increases as the solid circulation rate or particle size increases. The liquid radial dispersion coefficient is related closely to the resultant behavior of fluidized particles. The radial dispersion coefficient has been well correlated with operating variables in terms of dimensionless groups.

The rise velocities of bubbles, slugs and pressure waves in a fluidized bed have been measured on-line through the use of pressure transducers coupled with the tested. Effects of the gas flow rate and column diameter on the rise velocities of bubbles and slugs were investigated. The results were correlated with two models developed in this work and were compared with the data obtained by other investigators. L. T. FAN, THO-CHING HOcrosscorrelation technique. Sand and glass beads with different particle sizes were

A mathematical model was developed to describe the gasification of biomass in a fluid-bed reactor. The model was simplified, applied to the gasification of feedlot manwe, and a preliminary attempt was made to compute the gas composition and yields of gas, liquid, and solid products assumlng that the water-gas shift reaction was the only gas-phase reaction. The governing equations were solved by using a soltware Interface. Althu& the predicted and experimental values agreed reasonably well, the comparkon suggested that cracking and reforming reactions involving the volatiis produced during devolatitlzation should be included in the model. An approximate calculation of the gas yields and liquid yields incorporating the thermal cracking reactions of the heavy volatlles compared more favorably with the data.