Experimental and theoretical development of a thermal design tool for radiant domestic stoves. Paper no. IGEC-1-003

A steady-state space radiant heat model and a stove combustion model are developed to simulate the heat exchanges between various surfaces in the room and the stove and stack surfaces, assuming stiochiometric combustion inside the stove and the exhaust gases flow out through the stack by natural convection. The space heat model calculates the fuel consumption, the stove, stack temperatures, and the mass flow rate of exhaust gases, and provides an opportunity to study energy efficiency of stove, while satisfying the constraints of thermal comfort. Fanger (1982) model and a radiation exchange model between various surfaces of the space, the thermal building energy balance, and stove combustion process is applied to determine the mean radiant temperature (MRT) and the extent of thermal comfort as determined by predicted mean vote (PMV). The overall model is validated by performing experiments in a room placed inside controlled outdoor environment. The room is heated using a common domestic stove for rural areas of Lebanon. The measured MRT, the average room temperature, the wall surfaces temperatures agreed within ±7% of values predicted by the numerical model. A parametric study using the developed models reveals that the values of MRT and PMV depend strongly on the position of the radiant stove heater and stack with respect to the cold window and the occupant location. It is shown that it is possible to save up to 15% in fuel consumption of the stove by changing the stove position in the room with respect to the window and to the person, while maintaining the same level of comfort. (author)