Experimental investigation of the infiltration heat load during the opening of a refrigerated truck body.

Heat and volume infiltration rates have been measured during the opening of a refrigerated rigid truck body. Experiments were carried out for two inside temperatures of 0 and -20°C and for three outside temperatures of 5, 20 and 40°C. The infiltration dynamics was found to involve two distinct phenomena: (i) a gravitational flow and (ii) a boundary layer flow. The first is a density-driven flow which gives rise to an important heat load peak. This peak is quickly followed by a decay due to the temperature increase into the body. The second phenomenon, occurring up to the closing of the door, was due to the steady-state natural convection over the truck body inner wall.