HU186211B - Passive protecting apparatus for broken down outflow openning of heat carrier of atomic power station with water cooled reactor - Google Patents

Abstract

In order to guarantee the safety of a nuclear power plant having a water-cooled nuclear reactor in the event of accidental escape of the heat carrier, a passive protective system is provided in which the hermetic chambers of the primary coolant circuit are connected to a condensation system with bubble passage, which is connected in turn to a hermetic monolithic chamber. The condensation system consists of tubes immersed at different depths from the water surface of a water chamber and each fitted with a flat nozzle. These flat nozzles are embraced in each case by a channel with a converger and diffuser, the channel having a flat cross-section. The hermetic chamber can have a variable volume, for which purpose it is provided with a water seal and a movable cover. In this case, its volume increases even under minimum increase in pressure, and this makes it possible to dimension for substantially smaller design pressures. The different tube lengths and the design of the immersed tube ends with flat nozzles provide the preconditions that some of the tubes will be operated under stationary conditions even in the case of a relatively low throughput of the steam/air mixture. <IMAGE>

Description

BACKGROUND OF THE INVENTION The present invention relates to a passive protective device for a defective outlet of a water-cooled nuclear reactor of a nuclear reactor.

A defective outlet for a passive shielding device for a water-cooled nuclear reactor heat carrier having a hermetically sealed space in the primary circuit is connected to a Barbotage condensation system consisting of tubes of the same length immersed in cold water.

A disadvantage of the known apparatus is that the large cross-section of the steam-water stream entering the water space through the pipes and the large radius of the steam-air-water mixture thus formed result in large bubbles which are subjected to strong loads through condensation.

Because of the large bubbles, for maximum condensation of the vapor-air mixture vapor component, the mouthpieces have to be inserted deep into the water space, which results in a larger pipe length, which in turn results in increased flow resistances of the condenser. In addition, the non-stationary vapor-air price. it creates vapor condensation in the tubes themselves, which is accompanied by the suction of water from the water space. At a subsequent pressure rise, which is caused by a decrease in the condensation surface, the sucked water column is pushed back into the water column. These processes also cause significant dynamic loads in the equipment, expressed in non-stationary vibrations.

It is an object of the present invention to provide a passive shielding device for a defective spill opening of a water-cooled nuclear reactor nuclear power plant, the condensation contact surface of which has been enlarged and which allows for effective mixing of the vapor-air mixture with water stream L: making better use of its ethical energy.

According to the present invention, this object is solved by the condensation system consisting of tubes submerged at different depths relative to the water mirror, each outlet being provided with an outlet nozzle 1 at its lower end surrounded by a flat channel provided with a configurator and diffuser. In addition, the hermetic monolithic space for receiving air and other non-condensable gases is formed with a variable volume provided it has a movable lid and a water seal.

Advantages of the invention:

Provides effective mixing of the steam-air mixture with water in the water space with significantly increased condensation surface and minimal hydraulic losses. The apparatus allows the depth of the dip mouths to be immersed in the water space and thereby significantly reduce the pipe length and thus reduce the flow resistance of the condensation system. The structure also ensures that the dynamic loading of the equipment components is not too high even when the inlet steam-air mixture is not stationary. The variable volume of air and other non-condensable gas receiving space provided by the movable lid and the water seal makes it possible to scale this space to a much lower pressure.

DETAILED DESCRIPTION OF THE DRAWINGS The invention will be described in more detail with reference to the drawings, which illustrate an exemplary embodiment of the apparatus of the invention.

Figure 1 is a schematic sectional view of the apparatus.

Figure 2 is a schematic cross-sectional view of a pipe mouth opening into a water space.

The apparatus comprises a hermetically sealed space 1 in which a primary circular flow is separated from the pipe 3 by a heat-insulated damper 2. The pipeline 3 is connected to a collector 4, which in turn is connected to a Barbotage system. The condensation system consists of tubes 5 immersed in different depths relative to the water mirror. Each tube assembly is provided with a l'.pos 6 nozzles surrounded by a flat channel 7 with age diffuser and diffuser. The pipes 5 are submerged in the water channel 8. The water space 8 is connected by a non-return valve 9 to a hermetic monolithic space 10. The volume of the space 10 can be varied by the watertight seal 11 and the movable lid 12 in hard ebony.

The equipment works as follows. If the primary cycle is airtight; The seal is broken due to condensation of the outgoing heat carrier vapor, the pressure in the hermetic space 1 increases, which causes the damper 2 to open and the steam-air mixture to drain into the manifold 4 through the conduit. Throughout the tubes 5 of the tube bundle of tubes of different lengths each having a flat nozzle 6, the steam-air mixture enters the water space 8 while bringing cold water with it and mixing it to form a thin, flat jet. The resulting steam-water-air mixture then passes through a flat channel 7 provided with a configurator and a diffuser. The flat jet generated by the kinetic energy of the vapor-air mixture exiting the flat nozzle 6 flows at an increased rate through the flat channel 7, while requirements for effective condensation of the vapor-air mixture vapor component are met. Due to the different lengths of the tubes 5, it is possible for some of the tubes 5 to operate under steady-state conditions even with relatively low flow rates of the vapor-air mixture. The probability of an unstable (unstable) operation resulting from the absorption of water from the water space into the pipes 5 and subsequent ejection, resulting in significant dynamic loads and vibrations, is thus minimized. As a result of the increase in pressure over the water body 8, the non-return valve 9 opens, through which the wet air and gases fill the hermetic monolithic water space, where they remain until they lose their activity. If the space 10 has a variable cross-section, i.e. it is provided with a water seal 11 and a movable lid 12, its volume increases even if the pressure in the space increases only slightly.

Claims (1)

Patent claims 1. A passive protection device for a defective outlet of a water cooled nuclear fuel reactor nuclear power plant 2186211 having hermetic compartments in which the primary circuit is connected to a Barbotage condensation system, which in turn is connected to a condensation system and a hermetic monolithic 5) characterized in that the tubes (5) are provided with tubes (5) submerged at different depths with respect to the water mirror and with a flat nozzle (6) surrounding the outlet of each tube, which in turn is surrounded by a flat channel (7) with confuser and diffuser, and the hermetic space (10) is designed as a variable volume space. An embodiment of a protective device according to claim 1, characterized in that the hermetic space (10) is formed as a variable volume space by providing a water seal (11) and a movable lid (12).