Comfort temperature: Flawed status in the CIBSE Guide

Abstract

It is shown qualitatively and quantitatively that it is invalid to place the room comfort temperature t_c on the conductance ΣAh ₂ as is done in the model for room heat exchange in the 1986 CIBSE Guide. It is noted that the global value of comfort temperature T_c in a room is a low-conductance combination of the room air and radiant temperature while the temperature index T _i combining these measures in relation to bulk heat transfer is a high conductance construct; T and T _i cannot be represented simultaneously in a thermal circuit. Thus the Guide's use of segments of ΣAh _a and the factors F ₁ and F ₂ in the expression for the room heat Q_t are not logically sustainable.

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References

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