PHYSICAL PROPERTY AND ROTATIONAL SPEED EFFECTS ON HEAT-TRANSFER IN AXIALLY ROTATING LIQUID PARTICULATE CANNED FOODS

Particle surface temperatures were measured by liquid crystals that allowed unrestricted motion of the monitored particles. Liquid-particle film heat transfer coefficients (h(p)) were considerably higher than published values which were determined with particles attached to thermocouple wires. In general, as a result of the particle motion, hp increased with increasing rotational speed and increasing fluid viscosity. Furthermore, h(p) values were higher for Teflon spheres than for aluminum spheres. Results for the overall (heating medium/container wall/internal liquid) heat transfer coefficients were consistent with published observations.