The present disclosure provides a cooling system of an emergency cooling tank, which enables long-term cooling without refilling cooling water, in case of the change in a quantity of heat transferred to the emergency cooling tank according to a lapse of time upon an occurrence of an accident of a nuclear reactor, and a nuclear power plant having the same. The emergency cooling tank cooling system includes an emergency cooling tank configured to store cooling water therein, the cooling water receiving heat, transferred from a nuclear reactor or a containment, when an accident occurs in the nuclear reactor, a heat exchanging device installed to be exposed to an outside of the emergency cooling tank to operate in air, and configured to externally emit heat by way of a heat exchange between fluid in the emergency cooling tank and the air such that the operation of the emergency cooling tank is continued even without refilling the cooling water, and an opening and closing unit installed at an upper portion of the emergency cooling tank to be located higher than a water level of the cooling water, and configured to be open by a flow of the fluid generated by an evaporation of the cooling water, the flow being formed due to a pressure difference from external air at pressure higher than a preset pressure, such that some of the fluid is externally emitted when a heat load exceeding a cooling capacity of the emergency cooling tank is transferred.

Cooling system of emergency cooling tank and nuclear power plant having the same

The invention provides a two-phase flow device for researching the enhancement of the natural circulation capacity of a system. The two-phase flow device consists of a circulating water system, an air bubble generation device, an air supply system and a data acquisition system, wherein the circulating water system mainly comprises an open type water tank, a filter device, a heat exchanger and other relevant pipelines and valves; the air bubble generation device is a core of the device and consists of an external sleeve and a multiporous medium sleeve; the air supply system mainly comprises an air compressor, an air storage tank and a pressure reducing valve; the data acquisition system mainly consists of an integrated data acquisition system, a high-speed camera system, a gas mass flow meter, an electromagnetic flow meter, a pressure sensor and a temperature sensor. The two-phase flow device can effectively solve the problem of disturbance to a natural circulation system due to active air injection and reduce the additional resistance involved into a circulation loop; the device is simple, easy to operate and uniform in foaming; stable bubble flow can be obtained; the two-phase flow device is favorable for scientific design of natural circulation and two-phase flow and engineering design of a passive safety system.

Two-phase flow device for researching enhancement of natural circulation capacity of system

The invention relates to a test system for evaluating the local condensing heat transfer performance of mixed steam. The test system comprises a steam system, a cooling water loop and a data collection system, wherein an air compressor and an air drier of the steam system are connected, air enters a gas mixer together with steam in a boiler after passing through the air drier, and mixed gas enters a test section after being sufficiently mixed in the gas mixer; a water pump of the cooling water loop is used for conveying cooling water to the test section through a flowmeter from a water channel, a cooling water outlet of the test section is connected with an auxiliary cooling device, and the auxiliary cooling device is then connected with the water channel; four valves are arranged at the inlets and outlets of the test section, and are used for controlling the flow rates and pressures of the steam and cooling water respectively. The influence of non-condensable gas on condensation inside a horizontal light pipe can be evaluated by contrasting local condensing heat transfer coefficients.

Test system for evaluating local condensing heat transfer performance of mixed steam

The invention relates to a passive residual heat removal heat exchanger testing device which comprises a heat transfer testing section, a voltage stabilizer, a shield pump, a heater, a circulation pump, a heat exchanger, a high-level water tank, a low-level water tank, a lifting pump, a water supplying pump and a spraying pump, wherein the heat transfer testing section, the voltage stabilizer, the shield pump, and the heater form a main loop system of the testing device; the heat transfer testing section comprises 3 C-shaped heat transfer pipes and a cooling water tank; the voltage stabilizer is connected with an outlet pipeline of the heat transfer testing section and an inlet pipeline of the shield pump; the shield pump is connected with the outlet pipeline of the heat transfer testing section; the flowing amount of a main loop is adjusted by adjusting a valve and a bypass valve in front of the shield pump; the heater is arranged between the shield pump and the heat transfer testing section. According to the device, the forms, sizes and materials of the heat transfer pipes are designed reasonably, so that the stress deformation problem can be reasonably avoided, the water use amount can also be greatly reduced, the heat transfer process can be simulated relatively accurately, and relatively accurate heat transfer data can be obtained.

Passive residual heat removal heat exchanger testing device

The invention aims at providing a passive safety shell cooling system comprising a water tank, an inner evaporator pipe bundle, a steam-water separator and an outer air cooler, wherein the water tank is positioned in an annular cavity formed by an inner-layer concrete safety shell and an outer-layer concrete safety shell; the outer air cooler is positioned between the dome of the inner-layer concrete safety shell and the dome of the outer-layer concrete safety shell; both an inner evaporator and the steam-water separator are positioned inside the inner-layer concrete safety shell; two ends of the inner evaporator are respectively connected with the steam-water separator through two pipes; the steam-water separator is connected with the outer air cooler through a first pipe extending out of the inner-layer concrete safety shell; and the inner evaporator pipe bundle is communicated with the water tank through a second pipe extending out of the inner-layer concrete safety shell. When accidents such as LOCA (Loss Of Coolant Accident) and MSLB (Main Steam Line Break) occur, the passive safety shell cooling system can be used for safely and reliably conducting heat out of the safety shell for a long term, ensuring the temperature inside the safety shell, and guaranteeing that pressure is no more than a limiting design value, thereby maintaining the integrity of the safety shell.

Passive safety shell cooling system

Condensation heat-transfer experiment device capable of realizing coupling of natural circulation and forced circulation

The utility model provides a non-dynamic safety case cooling system comprising a pool, an internal vaporizer pipe truss, a vapor-water separator and an external air cooling device. The pool is arranged in a ring-shaped cavity combined by an inner layer concrete safety case and an outer layer concrete safety case. The external air cooling device is arranged between the domes of the inner layer concrete safety case and the outer layer concrete safety case. An internal vaporizer and the vapor-water separator are arranged in the inner layer concrete safety case. Two ends of the internal vaporizer are respectively connected with the vapor-water separator through two pipes. The vapor-water separator is connected with the external air cooling device through a first pipe extending out of the inner layer concrete safety case. The internal vaporizer pipe truss is communicated with the pool through a second pipe extending out of the inner layer concrete safety case. When accidents such as loss of coolant accident (LOCA) and main steam line burst (MSLB) happen, the non-dynamic safety case cooling system can safely and reliably conduct out heat in the safety case for a long term, ensures that the temperature and pressure in the safety case do not surpass designed limit values, and ensures integrity of the safety case.

Non-dynamic safety case cooling system

The invention aims to provide a passive residual heat exhausting system for a molten salt reactor. The passive residual heat exhausting system comprises a salt discharging pot, heat exchanging elements, a steam pocket and a ventilator, wherein the upper part of each heat exchanging element is located in the steam pocket, the lower part of each heat exchanging element is located in the salt discharging pot, and other parts of each heat exchanging element are located between the steam pocket and the salt discharging pot; each heat exchanging element comprises a heat transferring pipe; each heat transferring pipe is internally provided with a middle sleeve; each middle sleeve comprises an inner wall and an outer wall; a channel for steam to flow through is formed between each inner wall and the corresponding outer wall; a water inlet pipeline is formed in the inner wall of each middle sleeve, a water inlet is formed in the top of each water inlet pipeline, and the bottom end of each water inlet pipeline is disconnected and is communicated with the corresponding channel; the ventilator is internally provided with an air cooler; an air cooler inlet is formed in the end part of the air cooler and a fin pipe is arranged in the middle of the air cooler; the steam pocket is communicated with the air cooler inlet. According to the passive residual heat exhausting system for the molten salt reactor provided by the invention, the passive working capability of the system is improved, the problems of high fault rate and the like caused by the design of an active system are solved, and therefore, the safety of the residual heat exhausting system for the molten salt reactor is improved.

Passive residual heat exhausting system for molten salt reactor

The invention provides an experimental device for condensation heat-exchange of steam containing multi-component non-condensable gases. The experimental device comprises a steam supply system, an air supply system, a supply system of other gases, a cooling water system and a condensation experiment body, wherein the condensation experiment body comprises a shell and an experimental pipe arranged in the shell; the upper part and the lower part of the shell are respectively provided with an upper gas inlet pipe and a lower gas inlet pipe; an upper gas inlet valve and a lower gas inlet valve are respectively mounted on the upper gas inlet pipe and the lower gas inlet pipe; a main pipeline, which is formed after the upper gas inlet pipe and the lower gas inlet pipe are connected in parallel, is connected with the steam supply system, the air supply system and the supply system of other gases; the bottom of the shell is connected with a condensate tank; the steam is condensed in the condensation experiment body, and then the condensate flows down into the condensate tank from the bottom of the shell and is drained through a drain valve; and the upper end and the lower end of the experimental pipe are connected with the cooling water system. According to the experimental device for condensation heat-exchange of steam containing multi-component non-condensable gases, external condensation heat-exchange experiments of vertical single pipes and pipe bundles in various sizes and structural forms can be performed, thereby studying effect mechanisms of stem flow direction, non-condensable gas layers and other factors on condensation heat-exchange.

Ding Ming

Papers

Condensation heat-transfer experiment device capable of realizing coupling of natural circulation and forced circulation

Non-dynamic safety case cooling system

Passive residual heat exhausting system for molten salt reactor

Two-phase flow device for researching enhancement of natural circulation capacity of system

Experimental device for condensation heat-exchange of steam containing multi-component non-condensable gases