Thermal and hydraulic calculation of a Delta 125 steam generator for a power unit with an AP1000 reactor

Abstract

AP1000 power units have great advantages over VVER-1000 power units which are popular in Ukraine. They are equipped with passive safety systems that significantly reduce the risks of man-made accidents, even under conditions of extreme external influences. In addition, their design provides significant resource savings during construction and operation. The introduction of AP1000 reactors is not only a step towards restoring the country's energy potential, but also a strategic investment in the future. In this context, the thermal-hydraulic calculation of the Delta 125 steam generator, which is a key component of the AP1000 power unit, is extremely relevant and important to justify the feasibility of using such units in the Ukrainian power system. A comparative analysis of vertical and horizontal steam generators is carried out. The Delta 125 steam generator and its basic thermal scheme are described. The following thermal-hydraulic calculation was performed: the heat output of the economizer and evaporator sections, the coolant flow rate, the (t-Q)-diagram of the steam generator, the thickness of the walls of the heat transfer surface pipes and the length of the evaporator section pipes, and the heat transfer coefficient were calculated, the heat transfer surface area of the economizer and evaporator sections, the length and weight of the steam generator pipes, the hydraulic resistance of the first and second circuits, the sufficiency of the steam space for steam separation, the louver separator, the dimensions and weight of the main components of the body were determined. The cost of the steam generator, the estimated costs, and the dependence of the reduced costs on the coolant velocity were calculated.