Shell and tube recuperator thermal design of supercritical carbon dioxide cycle

Nowadays, due to the limitation of natural resources and the increase in energy demand, the use of modern cycles including the supercritical carbon dioxide cycle with high thermodynamic and economic efficiency is considered for energy production. In this research, the thermal design of the recuperator in two modes of recuperator cycle and split cycle has been done using relationships and hand calculations and compared with the results of HTRI and EDR softwares. In these designs, both large size tubes and microtubes are used. The results show that the number of the tubes of the heat exchanger in recuperator cycle with large size tubes is equal to 1840 with a diameter of 19.05 mm, while the same design with a microtube will be equal to 21815 with a diameter of 6.35 mm. In the split cycle, where the flow of cold fluid in the tube side is 35% of the recuperator cycle, the number of large size tubes is equal to 3267 and the design with microtubes is equal to 11679. Therefore, the design of new heat exchangers with microtubes is presented which is not a usual design procedure in the industry, but for the supercritical carbon dioxide fluid, it is under study and investigation by researchers.