# Essay On Heat Transfer

868 Words4 Pages
Introduction Heat transfer is an essential process involved in chemical engineering. This transfer mainly considers the change in temperature as its focus. Most of the processes involved in the industry tackle this type of transfer. To aid engineers and even students in understanding this, heat exchangers were created. Heat exchangers are devices designed to prevent other machines from overheating. And there are several types existing. One characteristic common to most heat exchangers is the transfer of heat from a hot phase to a cold phase with the two phases being separated by a solid boundary (Foust, 1980). The transfer of heat from the hot fluid to the wall or tube surface is attained by convection, through the tube wall by conduction,…show more content…
But this equation is only good for one material. In heat exchangers, the following equation is used: qhot = qcold + qloss where qloss is the heat lost by conduction in the tube walls. This quantity will determine how much heat has been lost during the experiment. Contributing to the value of qloss is the energy that is expected to escape to the outside environment through the shell-side of the exchanger. For an efficient system, qloss should be minimized (Guche, et al., 2016). On analyzing the heat transfer between two elements, another calculation is used and that is q = UAΔTlm where U is the overall heat transfer coefficient. This heat transfer coefficient is a function of the fluid properties and material composition of the heat exchanger. U varies based on the design of the heat exchanger. The variable q is the heat gained or lost by the system which can be calculated by q = mcPΔT. A is the heat transfer surface area. ΔTlm is the log-mean-temperature-difference which can be calculated via