Single thermal zone balance solved by Transfer Function Method

We present an algorithm that uses the Z-transform operator to face the problem of heat transmission in a single thermal zone composed by multilayered walls. The method is very flexible and could be adopted to calculate the transfer function coefficients able to simulate the thermal behaviour of a room in free floating. Knowing the transfer function coefficients, it is possible to simulate the dynamic profile of each inner surfaces temperature and furthermore of the inner air temperature. The proposed algorithm is fully described granting maximum clarity. The explicitness of all steps of the calculus make possible the definition of a method that is able to vary all of the calculus parameters such as sampling g period, number of roots, number of poles or number of coefficients. To assess the reliability of the algorithm, we carried out a comparison between simulation data obtained from our method, from Fourier steady-state algorithm and those obtained from TRNSYS.