InteriorWall represents heat storage within walls. It links a
variable number n of thermal resistances and capacities to a
series connection. n thus defines the spatial discretization of
thermal effects within the wall. All effects are considered as one-dimensional
normal to the wall's surface. This model is thought for interior wall
elements that only serve as heat storage elements. The RC-chain is defined via
a vector of capacities CInt[n] and a vector of resistances
RInt[n].
Resistances and capacities are connected alternately, starting with the first
resistance RInt[1], from heat port_a into the wall.