DE1815047A1 - Method and device for gas bubble separation from the coolant flow of a liquid-cooled nuclear reactor - Google Patents

Description

Serial No. 1523 December 16, 1968

B η / H s'

INTERATOM

Internationale Atomreaktorbau GmbH Bensberg / Cologne

Process and device for gas bubble separation from the coolant flow of a liquid-cooled

Nuclear reactor

The application relates to liquid cooled nuclear reactors in which deducted the heated in the reactor core cooling liquid which serves optionally simultaneously as a moderator, usually for the purpose of heat transfer at the upper end of the reactor core and after the heat release like in, a heat exchanger is again fed to the lower end of the reactor core. During this circulation of the coolant - either through external influences or through the circulation itself - gas bubbles can get into the coolant and be washed away with it.

If these gas bubbles also get into the reactor core, in particular also into the center of the reactor core, and there occupy a certain volume that is actually to be filled by the cooling liquid, this can pose a risk for

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the reactor, n'ird a certain gas bubble volume exceeded, then the nuclear reactor can in a few. Lilliseconds as a result of its excess iteactivity go through in order to prevent this, "should therefore der.Gasblasengehalt of the coolant is kept far below the critical limit or, if possible, at all prevents gas bubbles from reaching the center of the heater core.

This object is achieved with a method for separating in the coolant flow of a liquid-cooled Nuclear reactor entrained gas bubbles and to keep the gas bubbles away from the Iieaktorkern-Zentrum, in which according to the invention that in the lower part of the actuator or tank introduced coolant is guided in a helical downward forced circulation, the current on The lowest point is deflected radially and passed through the center of the Ileaktorkkern, with the gas bubbles above of the coolant flow and drawn off.

According to a further feature of the invention, it is considered particularly advantageous to carry out the method if in the lower part of the Seaktortank underneath the reactor core an annular channel for the coolant is provided, in the inlet nozzle provided with flow guide bodies open out and the channel via guide plates is in communication with a collecting space below, which is connected to the center of the reactor core via an internal chimney flows out.

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BATH ORIGINAL

According to a further feature of the invention is -of the ring-shaped channel separated from an outer chimney opening into the outskirts of the reactor core and attached to the ceiling At least one drainage opening is made in the canal.

The invention will be explained in more detail below with reference to the attached FIGS. 1 and 2. 'is show:

Fig. 1 is a side view of the lower part of the reactor J gate tank in section,

Fig. 2 the section AB according to Fir. \

./ie from Fi?;. 1, an annular channel 1 is provided in the reactor tank below the reactor core in the so-called Unterelenum, which is laterally bounded by the reactor tank 2 and the wall of the inner channel 3. One or more inlaid nozzles 4, which are provided within the canal rait 3trömm £ sleitkör; ..ern 5, open into the canal. The inner chimney 3 is surrounded at a distance by the outer λ chimney 6, which dips into the channel at the lower end and is connected to the edge zones of the reactor core at the upper end. In the lower area, the channel merges into a nursing room 7, which ignites in the inner chimney. A large number of guide plates 6 are arranged between the channel and the inner rabbit. In the ceiling? AbIaSIi ff mim: 1C for the glass bubbles is attached to the canal.

Lie new described above. Arrangement is now working viie follows:

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The coolant flow, which consists of three partial flows in the exemplary embodiment shown, enters the sub-plenum radially and is immediately deflected there by the flow guide body 5 in a tangential direction, namely all partial flows in the same pitch. The flow now runs in the channel 1 on a helical path with a slight slope directed downwards. While quite lances residence time of the coolant acting on the helical path in the channel to the mitgefvhrteir in the coolant flow glass bubbles tb two mutually perpendicular Strengthens, när.lich an upwardly directed buoyancy force and directed towards the axis of symmetry of the reactor tank force.

The force resulting therefrom leads to the majority of the gas cut against the slope opposite the liner vcn where they reach the discharge opening 10, wandering upwards. He reads the gas blowing, the other later out of the flow is eliminated, migrates radially inward from the coolant flow and reaches the outer chimney, which contains the Coolant for the liandzones of the reactor core in which a low gas bubble content of the coolant is not so disadvantageous ϊ / irkun ^ shows how in the center of the header core.

Most of the coolant is in the lower area This channel is directed by the guide plates 8 in the radial direction and fed to the center of the reactor core via the collecting space 7 and the inner chimney 3.

Infoige of the reduction provided according to the invention the flow velocity that is established

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BATH ORIGINAL

Pressure build-up in the diffuser 8 is an additional, repellent force exerted on the gas bubbles.

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Claims (4)

Serial Ur. 1523 December 16, 1968 1- ATE IT TA N'SPRÜCHE 1. Process for separating gas bubbles entrained in the coolant flow of a liquid-cooled nuclear reactor and for keeping the gas bubbles away from the reactor core center, characterized in that the coolant introduced into the lower part of the reactor tank in a helical downward direction Forced circulation, the flow deflected radially at the lowest point and through the center of the reactor core is performed, wherein the gas bubbles collect above the coolant flow and are drawn off. 2. Device for performing the method according to claim 1, characterized in that in the lower part of the reactor tank below the reactor core an annular channel (1) is provided for the coolant, in which is provided with flow guide bodies (5) Inlet port (4) open and that the channel via guide plates (8) with a collecting space below (7) is in connection, which opens into the center of the reactor core via an inner chimney (3). - II 009826/1086 -H- 3. Device according to claim 2, characterized in that of the annular Canal one that opens into the districts of the reactor core outer chimney (6) separated and at least one ^ pale opening (10) on the ceiling (9) of the channel is appropriate. 4. Device according to claim 2, characterized in that a diffuser (3) is arranged in the lower area of the lower lenum, which the flow · from the tangential direction in a radial lighting deflects, and thereby a reduction the o'trüiTiUngsgeschYiinäi. ~ effect. ^ I r. Lars teat It. General Power of Attorney 124, υ? 009826/1086 BATH Blank page