Movable shade Control Algorithm (&) Optimizing Control Conditions for Cold Seasons in Tehran City

The aim of this study is to prepare a proposed algorithm for computer simulation and determine the proper angle of dynamic exterior shades during the day. The control of the dynamic shade is based on internal temperature. By repeating internal temperature calculations in each time phase, The algorithm compares the results with the defined criterion temperature, and chooses the optimal result. Numerical finite difference is the method used for thermal building’s calculations. In the construction of the zone numerous nodes are placed through each fabric component and the heat balance equation for each node is discrete by Crank-Nicolson method. In order to analyze the performance of the dynamic shade, the obtained results have been compared with the fixed and no shade modes. 21 degrees Celsius was determined as comfort temperature and criteria temperature in the first analysis for controlling the dynamic shade. According to the results obtained from the first analysis, with the goal of receiving more solar radiation and improving the performance of the shade, 23 degrees Celsius was determined as control temperature in the second analysis. Based on the calculations done for a building with south transparent glazing in Tehran, the amount of thermal load for the month of December , for dynamic shade mode with control temperature of 23 degrees Celsius is 33 percent lower than the fixed shade mode. On the other hand, the maximum difference between internal and comfort temperature for dynamic and fixed shade mode is in order 2 and 4 degrees, thus the dynamic shade provides a better comfort condition and lower internal temperature fluctuation.