Automated Optimum Design of Refrigerated Warehouses

The main consideration in the design of refrigerated commercial warehouses, apart from energy required for operation, is the total cost (initial plus operating costs). There is no simple explicit relation between the total cost and the energy required to maintain the desired inside conditions. Qualitatively, one feels that a design involving less initial cost requires larger energy input and hence a higher operating cost. With limited energy resources, it is necessary to conserve energy or use it optimally. A unified approach to find the optimal combination of initial cost and operating cost (energy) is presented in this paper. Since the thickness of insulation is one of the important factors to be considered in reducing the external load and hence the energy requirements, the optimum building envelope and insulation thicknesses are found for a specified volume and location by using the interior penalty function method of optimization. The procedure outlined in this paper can be used for new as well as existing building to fulfill the functional requirements optimally and thus conserve the energy to the greatest possible extent. For the computation of heat gain, the design day, based on the average maximum solar air temperature computed from the hourly meteorological data, is chosen. The resulting computer program is used to find the effect of some of the parameters like wall thickness, type of insulation, orientation of building and economics model on the optimum design.