A Convective and Radiative Flux Sensor for Designing Thermal Comfort Controllers

Abstract

The recent scientific and technological progress in measuring heat flux has promoted new large-sized and short rise time sensors that are convenient for measurement on massive wall surfaces under unsteady-state conditions. The objective of this paper is to show the interest of measuring the energy balance on one of the massive parts of an enclosure to adjust the thermodynamic pro cesses involved in air quality control in a given space. Another objective of the paper is to re-examine the procedure for the design of radiant heating control to show the interest of using radiative flux sensors in a feedback control loop. The radiative flux, which influences the energy balance of the room, provides a phase lead function, which can be used to control low-inertia radiant panels. Such a phase lead or feedforward control is adequate for identifying the effect of quick thermal disturbances on radiant temperature. Since no deviation from the equivalent temperature set point is required, such a feedforward con trol can be theoretically perfect in meeting thermal comfort requirements, depending only on the ability to detect the thermal disturbances from radia tive measurements.

Keywords

Thermal comfort Radiative ambiances Heat flux measurement Feedforward control

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