Many refrigeration facilities operate only for a limited time during the day, and during those limited hours, the amount of cooling energy consumption is very high. In storage systems, the cooling energy required for part or all of the building cooling load is generated and stored during non-peak hours of electricity consumption and non-peak cooling load. One of the devices that are considered in various industries for refrigerating with the aim of reducing energy consumption and costs, is the use of ice bank system. Due to the increasing development of these systems, the discussion of optimization in them and achieving optimal heat transfer is particularly important. In this project, a cooling storage tank with a new design of simulated refrigerant pipe and the freezing process and ice formation in it were investigated. To increase heat transfer during the freezing process, a series of fins were placed on the pipes containing the refrigerant. By considering the volume of the fins consistent, different conditions in terms of number, thickness and diameter of the fins were investigated and among them, the most optimal structure in terms of ice formation time in the tank was obtained. The advantage of this design is the increase of heat transfer level as well as the reduction of computational costs, which is important in optimization studies. Numerical problem solving method was validated with experimental data, the results of which were in good agreement with the laboratory results. The results showed that using a pipe with fins system, freezing process time of coolant was reduced by more than 38% compared to the simple pipe system. By increasing the fins level, freezing process time reduces, but since the total volume of the refrigerant pipe and the fins are constant, the geometric characteristics of the fin must be determined according to the geometric characteristics of the tank and the number of refrigerant pipes. Keywords: Ice storage system, Freezing process, Ice bank, Refrigeration capacity, Air conditioning