Computational analysis of a double-shell solar house

A simplified, one-dimensional formulation is used to study the role of natural circulation in the double-shell solar house. We consider the house as a complex thermosiphon, in which air warmed in a greenhouse travels through a loop formed by double walls around the house. The air carries heat to be stored in the ground for later use and also acts as a buffer between the inner living space and the outdoors. The Boussinesq approximation is considered to be valid for the air between the double walls, and the transient governing equations are integrated until steady state conditions are reached. The shape of the house is achieved in the context of a one-dimensional formulation by changing the direction in which gravity acts relative to the flow direction. The model includes radiation in the form of a source term on the south side of the house, heat loss through all surfaces using appropriate U-values and heat storage in and recovery from the ground and living space itself. The model clearly indicates trends in the way airflow and temperature distributions around the loop are affected by varying each parameter.