Valeooscope - Air Conditioning System Thermal comfort loop

6. Thermal comfort

Thermal comfort is achieved when we reach a state of thermal neutrality. We feel neither too warm nor too cold. In physical terms, this state of neutrality means that the thermal flows created by metabolism and the exchanges with the exterior are in equilibrium. air we breathe out g Exchanges of mass, through the evaporation of sweat g Convective exchanges between the skin and the ambient air g Direct solar radiation or radiation reflected by objects g The production of energy (metabolism), part of which is dissipated as heat g Conduction between the inner body and the surface of the skin g Heat exchanges through the lungs, by emitting water vapour and a rise in the temperature of the

Thermal balance Thermal comfort is achieved when the flows of ener- gy to which the human body is exposed are balanced. The heat generated inside the body, which depends on our activity, must offset the energy flows with our environment. Humidity Very humid ambient air (60% and above) is almost saturated with water. Our skin can no longer release all the perspiration and we start to feel hot again. On the other hand, if the humidity of the air is 30%, then 70% of its capacity to store water vapour remains available. Perspiration evaporates more easily, helping to keep the body cool.

These flows correspond to the following mechanisms:

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