Model
In order to study the radiator dynamics and to analyze the respective influence on the overall system behaviour, a dynamic radiator model is required. When considering the radiator from an Eulerian perspective, the radiator dynamics can be modelled according to a dynamic heat balance in which the lumped thermal capacitance is assumed to be concentrated in the exhaust temperature node.
Psu is the thermal power supplied to the radiator and equals the net difference between the incoming and leaving heat flows as illustrated in figure below. The heat emission Pemission is described by means of the exponential relationship between the radiator performance and the logarithmic mean temperature difference according to the 2 equations below. The exhaust temperature of the radiator changes according to the supplied thermal power and the heat emission. The exponent nrad in the equation below determines the characteristic of the used end-unit. In case of a radiator it is (1,2 ... 1,34) and a convector (1,25 ... 1,45).
Parameters
By clicking on the end-unit (radiator/convector) the user is able to input the parameters which define the end-unit, see figure below. For plate radiators the KV-value depends on the number of plates, see list below.