Heat transfer to a canned corn starch dispersion under intermittent agitation

A thermorheological model for the heating a 3.5% corn starch dispersion (STD) was used together with a finite element based simulation software (FIDAP) to solve the governing mass, momentum and energy transport equations for heating the STD at 121 degreesC in a 303 x 406 axially rotating can. Heat transfer from the hot wall to the inner canned STD improved considerably in intermittent rotation because the boundary layer region was not covered with a thick layer of gelatinized starch. In comparison to the experimental data obtained in a Steritort(TM), the simulated time-temperature profile was conservative and was in reasonable agreement. Further, simulation results showed that increase in the retort temperature results in a higher relative volume average temperature. In contrast, increase in the reel rotational speed in the 5-12 rpm range brought about a reduction in the volume average temperature. (C) 2002 Elsevier Science Ltd. All rights reserved.