Thermal design guidelines for weight-sensitive problems

Abstract

Consulta en la Biblioteca ETSI Industriales (Riunet)

[EN] There is a problem to solve while dealing with mobile systems powered by electric energy, the total system is heavy because of the combination of thermal and electric engines and the storage system. This research is focused on the minimization of the weight by optimizing the size of some systems and subsystems. An economical analysis and a comparison between both criteria will be conducted. It also includes the study for different travel length insomuch that the weight tendency is different for longer travels; being shared the weight of the system, it becomes less significant and then is the operating cost which become greater. Two different cases are studied. It is determined the ideal diameter of a pipe system for different mass flows, as will be shown, the optimum diameter for minimum weight becomes bigger as the mass flow demanded increases. It is determined that the optimum diameter for minimum price is higher than the one for minimum weight for all diameters. For several days the weight added by the system is lower and even the optimal diameter can change. For another case treated, the size of a HRSG, it is determined that there is a range of heat exchange area between the system saved weight in a 1 day study. Once the travel becomes larger it saved weight for a wider range, so it is convenient to install one as bigger as possible because always increase the save, this tendency only change when a small ΔT inside the HRSG is reached. An economical criteria study of the HRSG shows that there is a reduction of cost for every HRSG size.