General correlation for maximum heat transfer to surfaces submerged in gas-fluidized beds

A general correlation is presented for predicting maximum heat transfer coefficient for surfaces submerged in gas-fluidized beds. It has been verified with data for horizontal and vertical cylinders and spheres in beds of a wide variety of particles and gases. The gases include air, cryogens, methane, CO2, ammonia, and R-12. The rage of parameters includes: heat transfer surface diameter 0.05-220 mm, particle diameter 31-15000 µm, pressure 0.026-0.95 MPa, and temperature 13-1028 °C. The 363 data points from 53 sources are predicted with a mean absolute deviation of 16.2%. Several other correlations were also compared to the same data but had much larger deviations.