CN111199807B

CN111199807B - Device for inhibiting steam discharge pressure vibration

Info

Publication number: CN111199807B
Application number: CN202010042866.4A
Authority: CN
Inventors: 顾汉洋; 肖瑶; 张伟; 叶亚楠; 胡晨; 俞胜之; 蒋朝飞; 王晓雁; 龚自力; 贾臻
Original assignee: Shanghai Jiaotong University
Current assignee: The 719th Research Institute of China State Shipbuilding Corp.
Priority date: 2020-01-15
Filing date: 2020-01-15
Publication date: 2021-07-02
Anticipated expiration: 2040-01-15
Also published as: CN111199807A

Abstract

The invention discloses a device for inhibiting steam discharge pressure vibration, which comprises a steam discharge pipeline, a pressure-inhibiting pool and foam metal, wherein a discharge hole is formed in the tail end of the steam discharge pipeline, the tail end of the steam discharge pipeline is immersed in the pressure-inhibiting pool, and the foam metal is wrapped on the peripheral side of the tail end of the steam discharge pipeline and covers the discharge hole. According to the device for inhibiting the steam pressure vibration, the foam metal is wrapped at the tail end of the steam discharge pipeline, the steam firstly passes through the foam metal and then enters the pressure inhibition pool to be contacted with the supercooled water in the pressure inhibition pool, and the low-frequency and high-strength pressure vibration generated by direct contact and condensation of the steam and the supercooled water can be effectively absorbed. And the adopted foam metal wrapping mode is a passive safety measure, namely the mode does not depend on external energy supply, and the reactor has effective pressure pulsation inhibiting capability under the condition of whether the reactor is in an accident or not.

Description

Device for inhibiting steam discharge pressure vibration

Technical Field

The invention belongs to the technical field of improvement of pressure discharge systems of reactor type nuclear power stations such as pressurized water reactors, boiling water reactors and the like, and particularly relates to a device for inhibiting steam discharge pressure vibration.

Background

The containment vessel of the land nuclear power station is large in size, when high-temperature and high-pressure gas in the reactor is discharged, the safety of the reactor can be guaranteed by means of the existing containment vessel spraying and safety injection system, and an accident instant pressure peak suppression measure is not needed. In marine conditions, however, it is desirable that the reactor be capable of handling pressure discharges without having a large free space. Meanwhile, in the third generation nuclear power station AP1000, a passive design is adopted, and an Automatic Depressurization System (ADS) plays an important role in ensuring the safety of the reactor.

Under the accident condition, in order to protect the overpressure of a primary circuit system or realize the passive water supplement of a safety injection tank to a reactor core, the water of the primary circuit is directly discharged into an internal replacement water tank (IRWST) after being subjected to certain pressure reduction in a high-temperature high-pressure steam mode. In the process that steam is condensed and absorbed by supercooled water, different pressure oscillation phenomena can be generated according to the mass flow rate of the steam, the aperture of the discharge hole and the temperature of the water tank, pressure pulsation higher than the pressure of a steam source can be generated under specific flow, the frequency of the pressure pulsation is low, the heat bearing capacity of the water tank cannot be enhanced, and a higher requirement is provided for the pressure bearing capacity of the water tank.

In the existing pressure suppression method, a bubbler is often additionally arranged at the tail end of a steam discharge pipeline, and pressure oscillation is suppressed through the structure of the bubbler, so that the pressure suppression method has the limitation that the pressure suppression effect on small flow is not obvious, and the probability of pressure sudden change (chugging phenomenon) of the small flow is higher.

Disclosure of Invention

The invention provides a device for inhibiting the pressure vibration of steam discharge aiming at the technical problems, and the device can effectively inhibit the low-frequency and high-intensity pressure vibration generated by the direct contact and condensation of steam and supercooled water through foam metal.

In order to solve the problems, the technical scheme of the invention is as follows:

the utility model provides a restrain steam discharge pressure vibration's device, includes steam discharging pipeline, suppression pond, foam metal, the discharge hole has been seted up to steam discharging pipeline end, the terminal submergence of steam discharging pipeline is in the suppression pond, the foam metal parcel is in the terminal week side of steam discharging pipeline, and cover the discharge hole.

Preferably, the tail end of the steam discharge pipeline is connected with a bubbler, the bubbler and the suppression pool are immersed in the suppression pool, and the foamed metal is wrapped on the peripheral side of the bubbler.

Preferably, the metal foam is not in direct contact with the steam discharge pipeline or the bubbler, a gap of 6-10mm is left between the metal foam and the steam discharge pipeline or the bubbler, and the remained gap can obviously improve the absorption capacity of the pressure vibration of the metal foam in a low-frequency region.

Preferably, the aperture of the foam metal is 1-10mm, and the foam metal with the aperture of 1-10mm can well absorb low-frequency and high-intensity pressure vibration generated by direct contact and condensation of steam and supercooled water.

Preferably, the foamed metal is wrapped on the periphery of the steam discharge pipeline or the bubbler in multiple layers, the pore diameter of each layer of foamed metal is different, the foamed metal protective layer with the different pore diameters can have vibration damping capacity in a wider frequency domain, and if the pore diameter is too small, the absorption capacity on pressure vibration frequency is greatly reduced.

Preferably, the thickness of the foam metal is 8-12mm, preferably 10mm, the thickness of the foam metal wrapping is within the range of 8-12mm, the pressure vibration frequency generated by the phenomenon of steam direct contact condensation can be well absorbed, and if the thickness is less than 8mm, the pressure vibration frequency absorption capacity is greatly reduced.

Due to the adoption of the technical scheme, compared with the prior art, the invention has the following advantages and positive effects:

according to the device for inhibiting the steam pressure vibration, the foam metal is wrapped at the tail end of the steam discharge pipeline, the steam firstly passes through the foam metal and then enters the pressure inhibition pool to be contacted with the supercooled water in the pressure inhibition pool, and the low-frequency and high-strength pressure vibration generated by direct contact and condensation of the steam and the supercooled water can be effectively absorbed. And the adopted foam metal wrapping mode is a passive safety measure, namely the mode does not depend on external energy supply, and the reactor has effective pressure pulsation inhibiting capability under the condition of whether the reactor is in an accident or not.

The steam pressure suppression device provided by the invention has low requirement on the volume, not only can be applied to a land nuclear power station to reduce the free space volume of a containment vessel, but also can be applied to a safety protection system of a non-land nuclear power station, and provides an effective pressure suppression mode for the non-land nuclear power station.

The steam pressure suppression device provided by the invention can adjust the pore diameter of each layer of foam metal based on different specific conditions to cope with pressure vibration of different frequency bands, can specifically analyze specific conditions, and has wide applicability.

Drawings

FIG. 1 is a schematic cross-sectional view of an apparatus for suppressing steam discharge pressure oscillations in an embodiment of the present invention;

fig. 2 is a spectral distribution diagram of steam underwater jet pressure vibration.

Description of reference numerals: 1-a steam discharge conduit; 2-a suppression pool; 3-a metal foam; 4-a bubbler.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments. Advantages and features of the present invention will become apparent from the following description and from the claims.

Referring to fig. 1, the device for suppressing the pressure vibration of the steam discharge comprises a steam discharge pipeline 1, a pressure suppression pool 2, a foam metal 3 and a bubbler 4, wherein a discharge hole is formed in the tail end of the steam discharge pipeline 1, the tail end of the steam discharge pipeline 1 is connected with the bubbler 4, the foam metal 3 wraps the tail end of the steam discharge pipeline 1 and the periphery of the bubbler 4 and covers the discharge hole, the tail end of the steam discharge and the bubbler 4 are immersed in the pressure suppression pool 2, and supercooled water is contained in the pressure suppression pool 2.

According to the device for inhibiting the steam pressure vibration, the foam metal 3 is wrapped at the tail end of the steam discharge pipeline 1, steam firstly passes through the foam metal 3 and then enters the pressure inhibition pool 2 to be in contact with the supercooled water in the pressure inhibition pool 2, and low-frequency and high-strength pressure vibration generated by direct contact and condensation of the steam and the supercooled water can be effectively absorbed. And the adopted mode of the foam metal 3 is a passive safety measure, namely the mode does not depend on external energy supply, and the reactor has effective pressure pulsation inhibiting capability under the condition of accidents of the reactor.

The steam pressure suppression device provided by the embodiment has low requirement on the volume, can be applied to a land nuclear power station to reduce the free space volume of a containment vessel, can also be applied to a safety protection system of a non-land nuclear power station, and provides an effective pressure suppression mode for the non-land nuclear power station.

In a preferred embodiment, the foam metal 3 is not directly contacted with the steam discharge pipeline 1 or the bubbler 4, a gap of 6-10mm is left between the foam metal 3 and the steam discharge pipeline 1 or the bubbler 4, and the remained gap has the function of increasing the thickness of the sound absorption material approximately, so that the sound absorption spectrum characteristic moves towards the low frequency direction, the sound absorption performance at the low frequency band is improved, and the absorption capacity of the pressure vibration of the foam metal 3 in the low frequency region can be obviously improved.

In the preferred embodiment, the aperture of the foam metal 3 is 1-10mm, and the foam metal 3 with the aperture of 1-10mm can well absorb the low-frequency and high-intensity pressure vibration generated by the direct contact and condensation of steam and supercooled water.

In a preferred embodiment, the metal foam 3 is wrapped on the periphery of the steam discharge pipeline 1 or the bubbler 4 in multiple layers, the pore size of each layer of metal foam 3 is different, the protective layer of the metal foam 3 with the different pore sizes can have damping capacity in a wider frequency domain, and the absorption capacity to pressure vibration frequency is greatly reduced when the pore size is too small.

The steam pressure suppression device provided in the preferred embodiment can adjust the pore size of each layer of the metal foam 3 based on different specific conditions to cope with pressure vibration of different frequency bands, can specifically analyze specific conditions, and has wide applicability.

Fig. 2 is a graph of amplitude versus frequency data of pressure oscillations for a given operating condition, and it can be seen that there are peaks in pressure at 100Hz and 200Hz, i.e., the pressure oscillations are of greater intensity at this frequency. Thus, in this case, it is necessary to install a double layer of metal foam 3 cladding, one layer having a small pore size of about one tenth of a millimeter and one layer having a large pore size of about several millimeters. Different apertures have different absorption performance for different frequencies, and the large-aperture metal foam 3 cladding is selected to be placed inside because the small-frequency amplitude is larger in the figure.

In a preferred embodiment, the thickness of the foam metal 3 is 8-12mm, preferably 10mm, the thickness of the foam metal 3 is 8-12mm, the pressure vibration frequency generated by the phenomenon of direct contact condensation of steam can be well absorbed, and if the thickness is less than 8mm, the pressure vibration frequency absorption capacity is greatly reduced.

The embodiments of the present invention have been described in detail with reference to the accompanying drawings, but the present invention is not limited to the above embodiments. Even if various changes are made to the present invention, it is still within the scope of the present invention if they fall within the scope of the claims of the present invention and their equivalents.

Claims

1. The device for inhibiting the pressure vibration of the steam discharge is characterized by comprising a steam discharge pipeline, a pressure-inhibiting pool and foam metal, wherein the tail end of the steam discharge pipeline is connected with a bubbler, the bubbler and the bubbler are immersed in the pressure-inhibiting pool, and the foam metal is wrapped on the peripheral side of the bubbler;

a gap of 6-10mm is reserved between the foam metal and the bubbler;

the foamed metal is wrapped on the periphery of the bubbler in multiple layers, and the pore diameter of each layer of foamed metal is different.

2. The apparatus for suppressing steam discharge pressure oscillations according to claim 1, characterized in that, said metal foam has a pore size of 1-10 mm.

3. The apparatus for suppressing steam discharge pressure oscillations according to claim 1, characterized in that, said metal foam has a thickness of 8-12 mm.