Heating characteristics of water containing flat substance with an underlayer plate heated by long-wave infraredradiation and/or hot-air convection are analyzed on a simulated electrical resistance-capacitance network that is equivalentto a given thermal system.
In the previous paper we presented analytical results for the case without underlayer plate S and, instead, with the rearsurface of heated substance
W thermally insulated. The present analysis assumes as before that only the surface of
W isheated and that the substance is heated only by thermal conduction. It also assumes that the irradiated heat flow input, apartfrom the hot-air input, is constant and that
W behaves like pure water.
In addition to the general analysis, two representative cases
W=1mm thick water, and S=10mm thick wood plate or 1mmthick steel plate are considered. Numerical calculations show that the temperature rises of
W during a constant dryingperiod are little affected compared with the previous insulated case, though temperature rises are greatly delayeddue to thermal capacitance and resistance of S and accordingly much more so for the wood plate case.
The theory and the analytical results were checked against published experimental numerical data.
In the previous paper, we defined and introduced evaporation resistor γ
v. Here, for the heating characteristics of
W, theimportance of the parameter, ratio of γ
vto convection heat transfer resistor γ
h is explained. Taking advantage of theparameter, guide lines for designing an infrared system heating water containg substance
W are added and fullyexplained.
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