A reactor measurement-pipe maintenance clamp apparatus includes a first clamp mechanism and a second clamp mechanism. The first clamp mechanism includes clamps to fix the measurement pipe between the clamps, first clamp operation bolts that are allowed to be turned by remote control from above a reactor core, and wedge mechanisms to convert the turning of the clamp operation bolts to displacement of the clamps in a radial direction of the diffuser to generate clamping forces for securing the measurement pipe. The second clamp mechanism includes a support clamp to hold the support, a second clamp operation bolt that is allowed to be turned by remote control from above the reactor core, and a wedge mechanism to convert the turning of the second clamp operation bolt to displacement of the support clamp in a tangential direction of the diffuser to generate clamping force for fixing the support.

A system that measures the temperature distribution of the reactor coolant flowing through the hot leg or cold leg pipes by measuring the speed of sound time delay. This concept uses radiation hardened and temperature tolerant ultrasonic signal drivers based on vacuum micro-electronic technology. The system employs ultrasonic signals propagated through water, and relies on the characteristic that the speed of sound changes as the density and temperature of the water changes. Thus, a measured difference in the speed of sound in water may be directly correlated to a temperature change of the water.

A system that measures the temperature distribution of the reactor coolant flowing through the hot leg or cold leg pipes by measuring the speed of sound time delay. This concept uses radiation hardened and temperature tolerant ultrasonic signal drivers based on vacuum micro-electronic technology. The system employs ultrasonic signals propagated through water, and relies on the characteristic that the speed of sound changes as the density and temperature of the water changes. Thus, a measured difference in the speed of sound in water may be directly correlated to a temperature change of the water.

A system that provides a direct indication of peak fuel rod centerline temperature and peak fuel rod clad temperature than conventionally inferred from the power distribution by directly and continuously measuring the fuel temperatures of the fuel pellets in one or more of the hottest fuel elements in the core. The peak fuel rod clad temperature is then obtained from the maximum measured peak fuel rod centerline temperature in combination with the maximum coolant core exit temperature and the minimum coolant flow rate.

A system that provides a direct indication of peak fuel rod centerline temperature and peak fuel rod clad temperature than conventionally inferred from the power distribution by directly and continuously measuring the fuel temperatures of the fuel pellets in one or more of the hottest fuel elements in the core. The peak fuel rod clad temperature is then obtained from the maximum measured peak fuel rod centerline temperature in combination with the maximum coolant core exit temperature and the minimum coolant flow rate.

A pressurized water reactor includes a primary reactor coolant circuit flown through by a primary reactor coolant during operation, and a chemical and volume control system for the primary reactor coolant. The chemical and volume control system includes, along the direction of flow of the primary reactor coolant, a letdown line, a high-pressure charging pump with a given discharge pressure, and a charging line leading to the primary reactor coolant circuit. The chemical and volume control system further includes a hydrogenation system with a hydrogen supply and a hydrogen feeding line. In order to achieve efficient and fast hydrogen injection into the primary reactor coolant, a high-pressure feeding pump is arranged in the feeding line to provide a gas pressure higher than the discharge pressure of the charging pump. The feeding line discharges into the charging line.

A pressurized water reactor includes a primary reactor coolant circuit flown through by a primary reactor coolant during operation, and a chemical and volume control system for the primary reactor coolant. The chemical and volume control system includes, along the direction of flow of the primary reactor coolant, a letdown line, a high-pressure charging pump with a given discharge pressure, and a charging line leading to the primary reactor coolant circuit. The chemical and volume control system further includes a hydrogenation system with a hydrogen supply and a hydrogen feeding line. In order to achieve efficient and fast hydrogen injection into the primary reactor coolant, a high-pressure feeding pump is arranged in the feeding line to provide a gas pressure higher than the discharge pressure of the charging pump. The feeding line discharges into the charging line.

The present disclosure relates to a narrow slit channel visualization experimental device and method under a six-degree-of-freedom motion condition. The system comprises a six-degree-of-freedom motion simulation platform, a main circulation loop, a cooling water system, an electric heating system and a bubble monitoring system, wherein the main circulation loop is composed of an S-shaped preheater, a three-surface visualization experimental section, a double-pipe condenser, a pressurizing circulating pump, a voltage stabilizer and related equipment, wherein the cooling water system is composed of the double-pipe condenser, a plate heat exchanger, a cooling tower, a cooling fan, a cooling water tank and related equipment, wherein the electric heating system is composed of a direct-current power supply, a low-voltage power controller and a transformer, and wherein the bubble monitoring system is composed of two high-speed cameras, a PIV measuring system and an electric servo module.

The present disclosure relates to a narrow slit channel visualization experimental device and method under a six-degree-of-freedom motion condition. The system comprises a six-degree-of-freedom motion simulation platform, a main circulation loop, a cooling water system, an electric heating system and a bubble monitoring system, wherein the main circulation loop is composed of an S-shaped preheater, a three-surface visualization experimental section, a double-pipe condenser, a pressurizing circulating pump, a voltage stabilizer and related equipment, wherein the cooling water system is composed of the double-pipe condenser, a plate heat exchanger, a cooling tower, a cooling fan, a cooling water tank and related equipment, wherein the electric heating system is composed of a direct-current power supply, a low-voltage power controller and a transformer, and wherein the bubble monitoring system is composed of two high-speed cameras, a PIV measuring system and an electric servo module.

The apparatus includes a flowmeter coupled a surface exposed to a flow channel. The flowmeter monitors a flow of coolant. The flowmeter includes a first temperature sensor that generates first temperature data based on measuring a first temperature of a first flowstream, a heating element coupled to the first temperature sensor where the heating element applies heat to the first temperature sensor through an interface, a second temperature sensor generates second temperature data based on measuring a second temperature of a second flowstream, the second temperature sensor being spaced apart from the heating element, and the second temperature sensor being at least partially insulated from the heating element so the second temperature data generated by the second temperature sensor is independent of heat generated by the heating element. A processor calculates a flowrate of the coolant based on the second temperature data and a temperature of the coolant fluid.