Reducing cooling loads with under roof air cavities.

In the present paper a model for steady-state thermal analysis of ventilated and unventilated light rook is proposed. The aim of the work is tostudy the influence of thermo-physical and geometric parameters of the roof and boundary conditions (solar radiation) on the entering heat flowand the temperature distribution within the roof structure.

A thermal sensation prediction tool for use by the profession.

As part of a recent ASHRAE research project (781-RP), a thermal sensation prediction tool has been developed. This paper introduces the tool, describes the component thermal sensation models, and presents examples of how the tool can be used in practice. Since the main end product of the HVAC industry is the comfort of occupants indoors, tools for predicting occupant thermal response can be an important asset to designers of indoor climate control systems. The software tool presented in this paper incorporates several existing models for predicting occupant comfort.

A simple model for free cooling calculations.

We present a simple model to calculate the energy loss by free cooling at night. The time dependence of the exhaust air and wall surface temperatures is predicted by a simplified dynamic model that couples air flow, heat transfer, and wall temperature. For given ventilation rate the model predicts that the total heat extracted from the building during the night can be maximized by increasing the heat exchanging surface area and the thermal effusivity, of the wall materials. The influence of ventilation rate on the heat removed by freecooling at night is discussed.

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