Abstarct: With fuel fetching its real prices, we will face sudden rises in fuel and energy costs, necessitating the energy consumption optimization experts to provide solutions so as to reduce the amount of consumption. The main part of the energy consumption in industries goes to boilers; they not only increase the consumption rates but also cause environmental pollutions. To develop more effective boilers there are different ways. One of these ways is to raise the initial temperature of the boiler. To achieve this goal, with the help of a heat exchanger, the heat of the fumes is taken and transferred to the air coming to the boiler. Of the different types of heat exchangers, the shell and tube heat exchangers are the most widely utilized in industry. To improve these types of heat exchangers one may use different kinds of baffles, like helical ones, or use tubes such as oval and swirl tubes or, finally, use the most important and easiest way that is to use fins. One of the significant results of using the above-mentioned ways is to make the size of the heat exchangers smaller, which have some considerable advantages, including the reduction of the manufacturing costs and they being more easily moved. The present thesis, first designs a tube and shell heat exchanger used in an industrial sugar factory, then, attempts to analyze the impact of the newest types of fins, known as sheet fins, on these heat exchangers. The basic advantage of this type of fins lies in their easy manufacturing and replacement. Regarding the main effects of using these fins in exchange heaters, one can refer to a ten-degree temperature rise in the boiler's initial air (air-preheater), compared to an exchanger without fins. Nonetheless, the increase of the exchanger's pressure drop can be considered a drawback in this method. It needs to be noted that in current study, for the first time, the arrangement of the fins has been changed and the impacts of such changes on the function of the exchanger has been analyzed.