Thermal comfort

Skin sensors: cold sensitivity K.s -1 hot sensitivity K.s -1 hypothalamus

Powe balance: S (W.m -2 )power balance M (W.m -2 )metabolism power W (W.m -2 )machanical power

R (W.m -2 )radiation C (W.m -2 )convection K (W.m -2 )conduction E (W.m -2 )evaporation RES (W.m -2 )respiration

Condition:

Metabolismus 1 Met = 58,15 W.m -2 Depended on human activity

Mechanical work For normal situations can be neglected

Evaporation cased by diffusion

p s (Pa)saturated wapor pressure t s p a (Pa)partial pressure of H2O φ (-)relative humidity t a (°C)air temperature Not controlled, typical value 10 W.m -2.

Sweat evaporation Depends on mass flow (g.m -2.s -1 ) from 1m 2 body surface

Respiration RES=L+E RES (W.m -2 ) (W.m -2 ), Typical value W.m -2

Radiation

Heat convection and conduction

Heat Comfort Equation

- Fanger’s equations of thermal comfort

PMV and PPD

An Example: