Method for improving external critical heat flux density of pressure vessel

Abstract

The invention aims to disclose a method for improving the external critical heat flux density of a pressure vessel. Compared with the prior art, the fluid between the outer wall surface of a reactor pressure vessel and a heat preservation layer can be stirred and mixed without depending on external alternating current, so that cold fluid on the side of the heat preservation layer cools the outer wall surface of the pressure vessel, and the steam content on the side of the wall surface is reduced, the CHF value outside the reactor pressure vessel can be greatly improved at the early stage of anaccident; even under the condition that a storage battery is exhausted, the fluid between the heat preservation layer and the wall surface of the pressure vessel can be stirred and mixed by means ofnatural circulation of the fluid in the reactor cavity, the CHF value of the outer wall surface of the pressure vessel is slightly increased, and the purpose of the invention is achieved.

Description

technical field [0001] The invention relates to a method for increasing the external critical heat flux density of a pressure vessel, in particular to a method for increasing the external critical heat flux density of a pressure vessel under a severe accident in a nuclear power plant. Background technique [0002] In-reactor retention of melt (IVR) is currently one of the most promising and important mitigation strategies for severe reactor accidents. The IVR measure is to inject water into the reactor cavity under the condition of an accident in the nuclear power plant, so that the reactor pressure vessel is immersed in water, relying on the boiling of water to cool the pressure vessel wall and maintain the integrity of the pressure vessel. However, the success of IVR measures needs to meet certain conditions, such as the heat flux on the pressure vessel wall must be less than the local critical heat flux (CHF). The ratio of the heat flux on the wall of the pressure vessel...

AI Technical Summary

Problems solved by technology

[0003] The heat flux on the wall of the pressure vessel is acted on the wall by the molten material after the core melts. Its magnitude is related to factors such as the power of the core and the total water content of the core. It is generally difficult to relate to the core system of the normal operation of the reactor Make major design improvements

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