Development of Technologies on Innovative-Simplified Nuclear Power Plant using High-Efficiency Steam Injectors - System Outline and Endurance Test of Low-Pressure Steam Injectors -

Abstract

A Steam Injector (SI) is a simple, compact and passive pump and also acts as a high-performance direct-contact heater. This provides SI with capability to serve also as a direct-contact feed-water heater that heats up feed-water by using extracted steam from turbine. Our technology development aims to significantly simplify equipment and reduce physical quantities by applying "High-Efficiency SI", which are applicable to a wide range of operation regimes beyond the performance and applicable range of existing SIs and enables unprecedented multistage and parallel operation, to the low-pressure feed-water heaters and Emergency Core Cooling System of nuclear power plants, as well as achieve high inherent safety to prevent severe accidents by keeping the core covered with water (a Severe Accident-Free Concept). This paper describes the results of the endurance and performance tests of low-pressure SIs for feed-water heaters with Jet-deaerator and core injection system.

Scale Model Test and Transient Analysis of Steam Injector Driven Passive Core Injection System for Innovative-Simplified Nuclear Power Plant

“…The innovative-simplified nuclear power plant as shown in Fig.2, consists of a simplified feed-water heating system, a passive core injection system (PCIS) and a passive containment cooling system (6),(9), (10) . Of these systems, the PCIS driven by high-efficiency SIs is a system that, in an accident such as a LOCA (loss of coolant accident), attains discharge pressure higher than the supply steam pressure to inject water into the reactor by operating the SIs using the pool water in the containment vessel as the source of water supply and the steam contained in the reactor as the source of pressurization energy as shown in Fig.3.…”

“…Of these systems, the PCIS driven by high-efficiency SIs is a system that, in an accident such as a LOCA (loss of coolant accident), attains discharge pressure higher than the supply steam pressure to inject water into the reactor by operating the SIs using the pool water in the containment vessel as the source of water supply and the steam contained in the reactor as the source of pressurization energy as shown in Fig.3. The SIs, passive equipment, is used to replace large rotating machines (active equipment) such as pumps and motors, eliminating the failure probabilities of such active equipment (9), (10) .…”

“…In a SI-driven PCIS, redundancy will be provided to ensure that the water and steam supply valves to the SIs open reliably, and when the valves open, the SIs will automatically start to inject water into the core to keep the core covered with water. Thus, the SI enables the development of systems with high inherent safety to save the core from severe accidents (a severe accident-free concept) (9), (10) .…”

“…We determined the target specifications of the SI-driven PCIS as shown in Table 1 (9), (10) . First, steam centered SIs are used for the high-pressure SI-driven PCIS operated at high steam pressures (8 to 2 MPa).…”

Numerical and experimental study of steam‐water two‐phase flow through steam jet pump

“…The SJP has been analyzed for district heating as well as for using as a pump . In the past 20 years, the SJP was studied by a number of researchers . They proposed that the SJP can be used for emergency core cooling and feedwater supply system in advanced nuclear reactors.…”