CN105653869A - Three-dimensional transient performance analysis method for supercritical water reactor core - Google Patents

Abstract

The invention discloses a three-dimensional transient performance analysis method for a supercritical water reactor core. The three-dimensional transient performance analysis method comprises the steps that 1, reactor core steady-state calculation is executed, power parameters and thermal engineering parameters are provided, and iterative coupling calculation is executed till reactor core steady-state power parameters and the thermal engineering parameters are constricted; 2, a reactor core initial state and an assembly cross section library are provided; 3, transient calculation is executed, the power parameters and the thermal engineering parameters are provided, iterative coupling calculation is executed till the reactor core steady-state power parameters and the thermal engineering parameters are constricted; 4, fine power distribution of dimension of thermoelement cells is obtained, thermoelement channel analysis is conducted, and finally safety evaluation key parameters are given; 5, whether the safety evaluation key parameters exceed the corresponding transient or accident safety limit or not is judged, feedback between physics and thermal-hydraulic power can be accurately described, precise reactor core three-dimensional power distribution is provided, and the technical effect of the transient process and the accident process of a supercritical water reactor are stimulated truly.

Description

A kind of supercritical water reactor reactor core Three dimensional transient method for analyzing performance

Technical field

The present invention relates to nuclear reactor designs research field, particularly relate to a kind of supercritical water reactor reactor core Three dimensional transient method for analyzing performance.

Background technology

The operating condition of supercritical water reactor (SCWR) is in its thermodynamic critical point (374 DEG C of water, 22.1MPa) more than, system thermal efficiency is high, good economy performance, but simultaneously, compared with conventional water cooled reator, supercritical water reactor operational factor is greatly improved, and core structure and coolant flow process relative complex, bring substantial amounts of core physics, thermal technology-technical barrier such as waterpower and safety analysis, wherein, strong nuclear heat coupled characteristic is one of supercritical water reactor Core Design key technology difficult problem with performance evaluation.

In the heteropathy event of supercritical water reactor, great majority are relevant to control rod action, control rod remarkable action event will cause the distribution distortion of supercritical water reactor core power, along with strong physics and thermal technology-Seepage-stress coupling effect, power changes in distribution will directly affect the maximum clad temperature of supercritical water reactor fuel, and clad temperature not transfinite be the very important Transient safety analysis rule of supercritical water reactor, for power abnormal distribution event, point heap or one-dimensional neutron dynamics model cannot correctly describe the spatial distribution of power, cannot accurately calculate power over time, for ensureing the envelope calculated, it is necessary for introducing substantial amounts of conservative to assume, in addition, supercritical water reactor is owing to inherently possessing strong nuclear heat coupled characteristic, its reactive and power abnormal distribution event transient process is more complicated, and conservative approach is not provided that its real response process, this makes designer be difficult to heteropathy event is carried out deep research and analysis, only the three-dimensional Neutron Time-Space Kinetics of coupling carries out Analysis of Transient with thermal technology-hydraulics, feedback between ability accurate description physics and thermal technology-waterpower, more accurate three-dimensional power distribution is provided, simulate transient process and the accident process of supercritical water reactor truly.

In prior art, for supercritical water reactor power abnormal distribution event, the transient state analyzing method adopted in the world, its neutron dynamics part adopts some heap or one-dimensional model, do not have the three-dimensional power calculation ability of reactor core nuclear heat coupling, it is difficult to truly or accurately simulate such as reactive and power abnormal distribution event transient process.

In sum, present inventor is in realizing the embodiment of the present application in the process of inventive technique scheme, it has been found that above-mentioned technology at least exists following technical problem:

In the prior art, existing supercritical water reactor power distribution transient state analyzing method exists and does not possess the three-dimensional power calculation ability of reactor core nuclear heat coupling, it is difficult to truly or accurately simulate the technical problem of the such as transient process of reactivity and power abnormal distribution event.

Summary of the invention

The invention provides a kind of supercritical water reactor reactor core Three dimensional transient method for analyzing performance, solve the distribution transient state analyzing method existence of existing supercritical water reactor power and do not possess the three-dimensional power calculation ability of reactor core nuclear heat coupling, it is difficult to truly or accurately simulate the technical problem of the such as transient process of reactivity and power abnormal distribution event, achieving can feedback between accurate description physics and thermal technology-waterpower, there is provided more accurate reactor core three-dimensional power to be distributed, simulate the transient process of supercritical water reactor and the technique effect of accident process truly.

For solving above-mentioned technical problem, the embodiment of the present application provides a kind of supercritical water reactor reactor core Three dimensional transient method for analyzing performance, and described method includes:

Step 1: supercritical water reactor reactor core three-dimensional steady state physics-thermal-hydraulic coupling module performs reactor core stable state and calculates, in-core fuel management module provides power parameter to subchannel thermal technology-hydraulic module, subchannel thermal technology-hydraulic module provides thermal parameter to in-core fuel management module, performs iteration coupling and calculates until reactor core steady state power parameter and thermal parameter are restrained;

Step 2: reactor core three-dimensional steady state physics-thermal-hydraulic coupling module provides reactor core original state and assembly cross-section library to supercritical water reactor reactor core Three dimensional transient physics-thermal-hydraulic coupling module;

Step 3: supercritical water reactor reactor core Three dimensional transient physics-thermal-hydraulic coupling module performs transient state and calculates, three-dimensional Neutron Time-Space Kinetics module provides power parameter to subchannel thermal technology-hydraulic module, subchannel thermal technology-hydraulic module provides thermal parameter to three-dimensional Neutron Time-Space Kinetics module, performs iteration coupling and calculates until reactor core transient power parameter and thermal parameter are restrained;

Step 4: in reactor core calculates, hot assembly is carried out power reconstruct and obtains the fine power distribution of hot assembly lattice cell yardstick, carry out hot assembly subchannel analysis again with subchannel thermal technology-hydraulic module, finally provide safety evaluation key parameter;

Step 5: judge whether described safety evaluation key parameter exceedes corresponding transient state or fail-safe limit value, evaluates supercritical water reactor reactor core security performance under transient process.

Further, described safety evaluation key parameter includes: maximum involucrum wall surface temperature, pellet heat content.

Further, reactor core three-dimensional Neutronics calculation uses few group cross-section, few group cross-section adopts the mode of piecewise interpolation to be processed into cross-section library in advance for reactor core three-dimensional neutronics module about the change of thermal parameter and parameter preset, and described parameter preset includes: fuel-assembly burn-up, with or without control rod.

Further, the coupling of described execution iteration calculates until reactor core steady state power parameter and thermal parameter convergence specifically include:

Start;

Read input file, initialization component few group cross-section, reactor core neutron flux;

Carry out subchannel thermal technology's module stable state to calculate;

It is updated cross section;

Carry out three-dimensional neutronics module stable state to calculate;

Carry out subchannel thermal technology's module stable state to calculate;

Judge whether core power distribution restrains, then return step if not and re-start renewal cross section;If then stable state calculates and terminates, enter transient state and calculate.

Further, described supercritical water reactor reactor core Three dimensional transient physics-thermal-hydraulic coupling module execution transient state calculates and specifically includes:

Start transient state to calculate;

Carry out time step renewal, prepare the initial value in n moment;

Carry out subchannel thermal technology's module transient state and calculate a time step;

It is updated cross section;

Carry out three-dimensional Neutron Time-Space Kinetics module transient state and calculate first time step;

Judge whether core power distribution restrains, then return if not and perform time step renewal, prepare the initial value in n moment; If then n=n+1; Judging that whether tn is less than T, wherein, tn was the n-th time step correspondence time, and T is that preassigned transient state calculated to the T moment, performing time step renewal if then returning, preparing the initial value in n moment; Then calculate if not and terminate.

Further, described supercritical water reactor reactor core three-dimensional steady state physics-thermal-hydraulic coupling module performs reactor core stable state and calculates and described supercritical water reactor reactor core Three dimensional transient physics-thermal-hydraulic coupling module execution transient state calculating, all adopts identical space method for solving: second kind boundary condition locking nub green function method. So to ensure the self-consistency of Neutronics calculation in three-dimensional steady state-transient state process of calculation analysis.

Further, the time discrete method that the three-dimensional Neutron Time-Space Kinetics module of described execution reactor core Three dimensional transient physical computing adopts is Euler's method backward. Wherein, Euler's method possesses definitely-stability backward, and is easy to the coupled in series exploitation of program.

The one or more technical schemes provided in the embodiment of the present application, at least have the following technical effect that or advantage:

Include owing to have employed to be designed as supercritical water reactor reactor core Three dimensional transient method for analyzing performance: step 1: supercritical water reactor reactor core three-dimensional steady state physics-thermal-hydraulic coupling module performs reactor core stable state and calculates, in-core fuel management module provides power parameter to subchannel thermal technology-hydraulic module, subchannel thermal technology-hydraulic module provides thermal parameter to in-core fuel management module, performs iteration coupling and calculates until reactor core steady state power parameter and thermal parameter are restrained; Step 2: reactor core three-dimensional steady state physics-thermal-hydraulic coupling module provides reactor core original state and assembly cross-section library to supercritical water reactor reactor core Three dimensional transient physics-thermal-hydraulic coupling module; Step 3: supercritical water reactor reactor core Three dimensional transient physics-thermal-hydraulic coupling module performs transient state and calculates, three-dimensional Neutron Time-Space Kinetics module provides power parameter to subchannel thermal technology-hydraulic module, subchannel thermal technology-hydraulic module provides thermal parameter to three-dimensional Neutron Time-Space Kinetics module, performs iteration coupling and calculates until reactor core transient power parameter and thermal parameter are restrained; Step 4: in reactor core calculates, hot assembly is carried out power reconstruct and obtains the fine power distribution of hot assembly lattice cell yardstick, carry out hot assembly subchannel analysis again with thermal technology's module, finally provide safety evaluation key parameter; Step 5: judge whether described safety evaluation key parameter exceedes corresponding transient state or fail-safe limit value, evaluate the technical scheme of supercritical water reactor reactor core security performance under transient process, namely Analysis of Transient is carried out by the three-dimensional Neutron Time-Space Kinetics of coupling with thermal technology-hydraulics, neutron dynamics part adopts threedimensional model, it is made to possess the three-dimensional power calculation ability of reactor core nuclear heat coupling, it is achieved the technique effect that supercritical water reactor reactor core Three dimensional transient is analyzed; So, efficiently solve the distribution transient state analyzing method existence of existing supercritical water reactor power and do not possess the three-dimensional power calculation ability of reactor core nuclear heat coupling, it is difficult to truly or accurately simulate the technical problem of the such as transient process of reactivity and power abnormal distribution event, achieve by setting up reactor core three-dimensional steady state-transient state physics-thermal-hydraulic coupling calculation process, can feedback between accurate description physics and thermal technology-waterpower, there is provided more accurate reactor core three-dimensional power to be distributed, simulate the transient process of supercritical water reactor and the technique effect of accident process truly.

Further, this method can simulate supercritical water reactor reactor core transient process truly, improves the understanding to supercritical water reactor reactor core transient condition, estimates safety allowance more accurately, improve Core Design and improve heap core performance.

Accompanying drawing explanation

For making the object, technical solutions and advantages of the present invention clearly understand, below in conjunction with embodiment and accompanying drawing, the present invention is described in further detail, and exemplary embodiment and the explanation thereof of the present invention are only used for explaining the present invention, not as a limitation of the invention.

Fig. 1 is supercritical water reactor reactor core three-dimensional steady state-transient state physics-thermal-hydraulic coupling calculation process schematic diagram;

Fig. 2 is supercritical water reactor reactor core Three dimensional transient method for analyzing performance stable state calculation process schematic diagram;

Fig. 3 is the signal of supercritical water reactor reactor core Three dimensional transient method for analyzing performance transient state calculation process;

Fig. 4 is Euler's method instantaneous neutron calculation process schematic diagram backward.

Detailed description of the invention

The invention provides a kind of supercritical water reactor reactor core Three dimensional transient method for analyzing performance, solve the distribution transient state analyzing method existence of existing supercritical water reactor power and do not possess the three-dimensional power calculation ability of reactor core nuclear heat coupling, it is difficult to truly or accurately simulate the technical problem of the such as transient process of reactivity and power abnormal distribution event, achieving can feedback between accurate description physics and thermal technology-waterpower, there is provided more accurate reactor core three-dimensional power to be distributed, simulate the transient process of supercritical water reactor and the technique effect of accident process truly.

Technical scheme in the application enforcement is for solving above-mentioned technical problem. General thought is as follows:

Have employed to be designed as supercritical water reactor reactor core Three dimensional transient method for analyzing performance and include: step 1: supercritical water reactor reactor core three-dimensional steady state physics-thermal-hydraulic coupling module performs reactor core stable state and calculates, in-core fuel management module provides power parameter to subchannel thermal technology-hydraulic module, subchannel thermal technology-hydraulic module provides thermal parameter to in-core fuel management module, performs iteration coupling and calculates until reactor core steady state power parameter and thermal parameter are restrained; Step 2: reactor core three-dimensional steady state physics-thermal-hydraulic coupling module provides reactor core original state and assembly cross-section library to supercritical water reactor reactor core Three dimensional transient physics-thermal-hydraulic coupling module; Step 3: supercritical water reactor reactor core Three dimensional transient physics-thermal-hydraulic coupling module performs transient state and calculates, three-dimensional Neutron Time-Space Kinetics module provides power parameter to subchannel thermal technology-hydraulic module, subchannel thermal technology-hydraulic module provides thermal parameter to three-dimensional Neutron Time-Space Kinetics module, performs iteration coupling and calculates until reactor core transient power parameter and thermal parameter are restrained; Step 4: in reactor core calculates, hot assembly is carried out power reconstruct and obtains the fine power distribution of hot assembly lattice cell yardstick, carry out hot assembly subchannel analysis again with thermal technology's module, finally provide safety evaluation key parameter; Step 5: judge whether described safety evaluation key parameter exceedes corresponding transient state or fail-safe limit value, evaluate the technical scheme of supercritical water reactor reactor core security performance under transient process, namely Analysis of Transient is carried out by the three-dimensional Neutron Time-Space Kinetics of coupling with thermal technology-hydraulics, neutron dynamics part adopts threedimensional model, it is made to possess the three-dimensional power calculation ability of reactor core nuclear heat coupling, it is achieved the technique effect that supercritical water reactor reactor core Three dimensional transient is analyzed; So, efficiently solve the distribution transient state analyzing method existence of existing supercritical water reactor power and do not possess the three-dimensional power calculation ability of reactor core nuclear heat coupling, it is difficult to truly or accurately simulate the technical problem of the such as transient process of reactivity and power abnormal distribution event, achieve by setting up reactor core three-dimensional steady state-transient state physics-thermal-hydraulic coupling calculation process, can feedback between accurate description physics and thermal technology-waterpower, there is provided more accurate reactor core three-dimensional power to be distributed, simulate the transient process of supercritical water reactor and the technique effect of accident process truly.

In order to be better understood from technique scheme, below in conjunction with Figure of description and specific embodiment, technique scheme is described in detail.

Embodiment one:

In embodiment one, it is provided that a kind of supercritical water reactor reactor core Three dimensional transient method for analyzing performance, refer to Fig. 1-Fig. 4, described method includes:

Step 1: supercritical water reactor reactor core three-dimensional steady state physics-thermal-hydraulic coupling module performs reactor core stable state and calculates, in-core fuel management module provides power parameter to subchannel thermal technology-hydraulic module, subchannel thermal technology-hydraulic module provides thermal parameter to in-core fuel management module, performs iteration coupling and calculates until reactor core steady state power parameter and thermal parameter are restrained;

Step 2: reactor core three-dimensional steady state physics-thermal-hydraulic coupling module provides reactor core original state and assembly cross-section library to supercritical water reactor reactor core Three dimensional transient physics-thermal-hydraulic coupling module;

Step 3: supercritical water reactor reactor core Three dimensional transient physics-thermal-hydraulic coupling module performs transient state and calculates, three-dimensional Neutron Time-Space Kinetics module provides power parameter to subchannel thermal technology-hydraulic module, subchannel thermal technology-hydraulic module provides thermal parameter to three-dimensional Neutron Time-Space Kinetics module, performs iteration coupling and calculates until reactor core transient power parameter and thermal parameter are restrained;

Step 4: in reactor core calculates, hot assembly is carried out power reconstruct and obtains the fine power distribution of hot assembly lattice cell yardstick, carry out hot assembly subchannel analysis again with thermal technology's module, finally provide safety evaluation key parameter;

Step 5: judge whether described safety evaluation key parameter exceedes corresponding transient state or fail-safe limit value, evaluates supercritical water reactor reactor core security performance under transient process.

Wherein, in the embodiment of the present application, described safety evaluation key parameter includes but not limited to: maximum involucrum wall surface temperature, pellet heat content.

Wherein, in actual applications, it is 850 DEG C that the safety limit that above-mentioned safety evaluation key parameter is corresponding is respectively as follows: under maximum involucrum wall surface temperature transient condition safety limit, and under accident conditions, safety limit is 1260 DEG C; Under pellet heat content transient condition, safety limit is 170cal/g, and under accident conditions, safety limit is 230cal/g. (under accident conditions, safety criterion requires that occurring without excessive reactor core damages; Under transient condition, safety criterion requires to occur without systematicness fuel rod damage, fuel pellet damages. )

Wherein, in the embodiment of the present application, using few group cross-section in reactor core calculates, few group cross-section adopts the mode of piecewise interpolation to be processed into cross-section library in advance for piling core module about the change of thermal parameter and parameter preset, and described parameter preset includes but not limited to: burnup, with or without control rod.

Wherein, in the embodiment of the present application, the coupling of described execution iteration calculates until reactor core steady state power parameter and thermal parameter convergence specifically include:

Start;

Read input file, initialization component few group cross-section, reactor core neutron flux;

Carry out subchannel thermal technology's module stable state to calculate, according to initial component few group cross-section, reactor core neutron flux, calculate heap in-core moderator-density and coolant density distribution;

It is updated cross section, is distributed according to moderator-density and coolant density, the few group cross-section of interpolation calculation assembly;

Carry out three-dimensional neutronics module stable state to calculate, according to the few group cross-section of new assembly, calculate and obtain assembly average power distribution, update reactor core neutron flux;

Carry out subchannel thermal technology's module stable state to calculate, according to new assembly few group cross-section, reactor core neutron flux, calculate heap in-core moderator-density and coolant density distribution;

Judge whether power distribution restrains, then return step if not and re-start renewal cross section; If then stable state calculates and terminates, enter transient state and calculate.

Wherein, in the embodiment of the present application, described supercritical water reactor reactor core Three dimensional transient physics-thermal-hydraulic coupling module execution transient state calculates and specifically includes:

Start transient state to calculate;

Carry out time step renewal, prepare the initial value in n moment;

Carry out subchannel thermal technology's module transient state and calculate a time step, according to the few group cross-section of initial component, core power distribution, calculate heap in-core moderator-density and coolant density distribution;

It is updated cross section, is distributed according to moderator-density and coolant density, the few group cross-section of interpolation calculation assembly;

Carry out three-dimensional Neutron Time-Space Kinetics module transient state and calculate first time step, according to the few group cross-section of new assembly, calculate and obtain core power distribution;

Judge whether power distribution restrains, then return if not and perform time step renewal, prepare the initial value in n moment; If then n=n+1, it is judged that whether the n-th time step correspondence time tn calculates time T less than preassigned transient state, performing time step renewal if then returning, preparing the initial value in n moment; Then calculate if not and terminate.

Further, described supercritical water reactor reactor core three-dimensional steady state physics-thermal-hydraulic coupling module performs reactor core stable state and calculates and described supercritical water reactor reactor core Three dimensional transient physics-thermal-hydraulic coupling module execution transient state calculating, all adopts identical space method for solving: second kind boundary condition locking nub green function method. So to ensure the self-consistency of Neutronics calculation in three-dimensional steady state-transient state process of calculation analysis.

Second kind boundary condition locking nub green function method solution throughway is as follows:

Three-dimensional Neutron Time-Space Kinetics equation form to be solved is:

$\left\{\begin{array}{c}\frac{1}{v_g}\frac{\∂{\mathrm{\φ}}_g(\stackrel{\→}{r},t)}{\∂t}-\▿\·D_g\▿{\mathrm{\φ}}_g(\stackrel{\→}{r},t)=\underset{g^{\′}\≠g}{\Σ}{\Σ}_{s,g^{\′}\→g}{\mathrm{\φ}}_{g^{\′}}(\stackrel{\→}{r},t)+{\mathrm{\χ}}_g(1-\mathrm{\β})\underset{g^{\′}=1}{\overset{G}{\Σ}}v{\Σ}_{f,g^{\′}}{\mathrm{\φ}}_{g^{\′}}(\stackrel{\→}{r},t)\\ +\underset{i=1}{\overset{ND}{\Σ}}{x}_{g,j}{\mathrm{\λ}}_i{C}_i(\stackrel{\→}{r},t),g=1,\mathrm{...},G\\ \frac{\∂{\mathrm{\φ}}_g(\stackrel{\→}{r},t)}{\∂t}={\mathrm{\β}}_i\underset{g^{\′}=1}{\overset{G}{\Σ}}{\mathrm{v\Σ}}_{f,g^{\′}}{\mathrm{\φ}}_g(\stackrel{\→}{r},t)-{\mathrm{\λ}}_i{C}_i(\stackrel{\→}{r},t),i=1,\mathrm{...},ND\end{array}\right.---\left(1\right)$

Wherein, g characterizes energy group, group can add up to G; v_gCharacterize g group's neutron speed, unit cm s^-1;Characterize g group's neutron flux, unit cm^-2��s^-1; D_gCharacterize g group diffusion coefficient, unit cm; ��_r,gAnd ��_f,gCharacterize g group removal cross-section and fission cross section, �� respectively_{s,g���g}Characterize the g ' group scattering section to g group, unit cm^-1; ��_gCharacterize prompt neutron fission spectrum; �� characterizes fission release neutron population every time; I characterizes delayed-neutron precursor packet, and pioneer's core group adds up to ND; ��_g,iCharacterize i-th group of delayed neutron spectrum share; ��_iCharacterize i-th group of delayed-neutron precursor decay constant, unit s^-1;Characterize i-th group of delayed-neutron precursor concentration, unit cm^-3; ��_iCharacterize i-th group of delayed neutron fraction.

For solving Transient Equations group (1), can remember�� t=t-t₀, y₁=y (t), y₀=y (t₀), wherein t characterizes current moment to be solved, t₀Characterized a upper moment. F (t, y) characterizes the summation that in equation group (1), non-temporal local derviation is several, then equation group (1) can be abbreviated as:

$\frac{\∂y}{\∂t}=f(t,y)---\left(2\right)$

The time discrete of equation adopts A-stably Euler scheme backward, can obtain:

y₁=y₀+��t��f(t,y₁)(3)

Applying Euler scheme backward, pioneer's nuclear concentration equation is discrete is:

Similarly, neutron flux equation is discrete is:

Formula (4), formula (5) being substituted into neutron diffusion equation, obtains formula (6), problem is converted into a stationary source problem:

$-\▿\·D_g\▿{\mathrm{\φ}}_g(\stackrel{\→}{r},t)+{\mathrm{\Σ}}_{r,g}{\mathrm{\φ}}_g(\stackrel{\→}{r},t)=-\frac{1}{v_g}\frac{{\mathrm{\φ}}_g(\stackrel{\→}{r},t)}{\mathrm{\Δ}t}+{\hat{Q}}_g(\stackrel{\→}{r},t)+S_g(\stackrel{\→}{r},t_0)---\left(6\right)$

Stationary source equation (6) adopts the locking nub green function method based on second kind boundary condition to solve, and solution throughway is as follows:

1, introduce second kind boundary condition Green's function and obtain the Integral Solution of the horizontal inclined neutron flux equation of integration;

2, utilize the condition of continuity of the non-homogeneous flux in locking nub interface and stream, obtain the corresponding matrix of interface mean net neutron current;

3, inclined neutron flux, pioneer's nuclear concentration, transverse leakage item all adopt 2 rank Legendre polynomial expansions, adopt Weighted residue method, solve inclined neutron flux expansion coefficient;

4, solve locking nub neutron balance equation and obtain neutron average flux, and then revise inclined neutron flux expansion coefficient.

In locking nub Green's function solution procedure, reactor core is divided into the basic computational ele-ment that several nuclear cross sections are identical, is referred to as locking nub. Using the locking nub minimum unit as spatial spreading, k characterizes locking nub numbering, x, y, and the definition territory of z direction coordinate is:

$x\∈\[-a_x^k,a_x^k\],y\∈\[-a_y^k,a_y^k\],z\∈\[-a_z^k,a_z^k\]---\left(7\right)$

Illustrate for x direction. Along y, z both direction to formula (6) integration in locking nub k, the inclined neutron flux equation in x direction can be obtained:

$-D_g\frac{{\∂}^2}{\∂x^2}{\mathrm{\φ}}_{gx}^k(x,t)+{\mathrm{\Σ}}_{r,g}^k{\mathrm{\φ}}_{gx}^k(x,t)=-\frac{1}{v_g}\frac{{\mathrm{\φ}}_{gx}^k(x,t)}{\mathrm{\Δ}t}+{\hat{Q}}_{gx}^k(x,t)-L_{gx}^k(x,t)+S_{gx}^k(x,t_0)---\left(8\right)$

In formula,Characterize horizontal fluence, source item, fixing source item, transverse leakage item respectively.

Introduce Green's function, then obtain the Integral Solution of inclined neutron flux equation:

$\left\{\begin{array}{c}{\mathrm{\φ}}_{gx}^k(x,t)+\underset{-a_x^k}{\overset{a_x^k}{\∫}}\frac{1}{v_g}\frac{{\mathrm{\φ}}_{gx}^k(x_0,t)}{\mathrm{\Δ}t}{G}_{gx}^k(x,x_0){\mathrm{dx}}_0=\\ \underset{-a_x^k}{\overset{a_x^k}{\∫}}\[{\hat{Q}}_{gx}^k(x_0,t)-L_{gx}^k(x_0,t)+S_{gx}(x_0,t_0)\]G_{gx}^k(x,x_0){\mathrm{dx}}_0\\ -G_{gx}^k(x,a_x^k)J_{gx}^k(a_x^k,t)+G_{gx}^k(x,-a_x^k)J_{gx}^k(-a_x^k,t)\end{array}\right.---\left(9\right)$

In formula,Characterize the Green's function based on second kind boundary condition.

Non-homogeneous flux and clean neutron current are continuous on adjacent locking nub interface. Non-homogeneous flux continuous print expression formula is:

$f_{gx+}^k{\mathrm{\φ}}_{gx}^k(a_x^k,t)=f_{gx-}^{k+1}{\mathrm{\φ}}_{gx}^{k+1}(-a_x^{k+1},t)---\left(10\right)$

Wherein,Characterize g group's discontinuous factor of the positive end points in k locking nub x coordinate direction.Characterize the negative terminal discontinuous factor of x coordinate direction k+1 locking nub.

Formula (9) is substituted into formula (10), utilizes the clean neutron current condition of continuity simultaneously, can obtain:

$\begin{array}{c}{f}_{gx+}^k{T}_{gx}^k{J}_{gx}^{k-1}(a_x^{k-1},t)-\[f_{gx+}^k{R}_{gx}^k+f_{gx-}^{k+1}{R}_{gx}^{k+1}\]J_{gx}^k(a_x^k,t)\\ +f_{gx-}^k{T}_{gx}^k{J}_{gx}^{k-1}(a_x^{k-1},t)=f_{gx-}^{k+1}{\[GQ-\]}_{gx}^{k+1}\left(t\right)-f_{gx+}^k{\[GQ+\]}_{gx}^k\left(t\right)\end{array}---\left(11\right)$

Formula (11) gives the clean neutron current coupled relation on the internal interface of k locking nub x coordinate direction. In outside interface, neutron current condition can be obtained by reactor core boundary condition, and then obtains the clean neutron current response matrix of this row locking nub. For reactor core x direction left margin:

1, by locking nub border reflective symmetry condition, can obtain:

$J_{gx}^1(-a_x^1,t)=0---\left(12\right)$

2, it is 0 condition by incident flow, can obtain:

$J_{gx}^{in,1}(-a_x^1,t)=\frac{1}{4}\left({\mathrm{\φ}}_{gx}^1\right(-a_x^1,t)f_{gx-}^1+2\·J_{gx}^1(-a_x^1,t))=0---\left(13\right)$

Formula (9) is substituted into formula (13), can obtain:

$(R_{gx}^1{f}_{gx-}^1+2)\·J_{gx}^1(-a_x^1,t)-T_{gx}^1\·J_{gx}^1(a_x^1,t)f_{gx-}^1=-2\·{\[GQ-\]}_{gx}^1{f}_{gx-}^1---\left(14\right)$

3, it is 0 condition by border flux, can obtain:

${\mathrm{\φ}}_{gx}^1(-a_x^1,t)f_{gx-}^1=0---\left(15\right)$

Formula (9) is substituted into formula (15), can obtain:

$R_{gx}^1\·J_{gx}^1(-a_x^1,t)f_{gx-}^1-T_{gx}^1\·J_{gx}^1(a_x^1,t)f_{gx-}^1=-2\·{\[GQ-\]}_{gx}^1{f}_{gx-}^1+{\mathrm{\Φ}}_{gx-}^1---\left(16\right)$

4, by 90 �� of rotationally symmetrical conditions, can obtain:

$J_{gx}^1(-a_x^1,t)=-J_{gy}^1(-a_y^1,t)---\left(17\right)$

Above-mentioned boundary condition is applicable to reactor core radially, can by reactor core x direction and y direction locking nub Unified Solution.

Neutron balance equation can pass through in locking nub k, formula (6) volume integral to be obtained:

$\begin{array}{c}({\mathrm{\Σ}}_{r,g}^k+\frac{1}{v_g{\mathrm{\Δt}}_j}){\stackrel{\‾}{\mathrm{\φ}}}_g^k\left(t\right)={\stackrel{\‾}{S}}_g^k\left(t_0\right)+{\stackrel{\‾}{\hat{Q}}}_g^k\left(t\right)\\ -\underset{u=x,y,z}{\mathrm{\Σ}}\frac{1}{2a_u^k}\[J_{gu}^k(a_u^k,t)-J_{gu}^k(-a_u^k,t)\]\end{array}---\left(18\right)$

In formula, u=x, y, z,Characterize locking nub volume-averaged flux, source item, fixing source item respectively.

The equation group of skew integration Flux Distribution, interface net flow, node average flux is constituted based on inclined neutron flux equation Integral Solution formula (9) of Green's function, clean neutron current coupled relation formula (11), neutron balance equation formula (18) based on Nodal method. Characterizing x, y, z coordinate with coordinate u, the one-dimensional abundance such as inclined flux, source, transverse leakage, by 2 rank Legendre polynomial expansions, can obtain:

${\mathrm{\φ}}_{gu}^k(u,t)=\underset{n=1}{\overset{3}{\Σ}}{\mathrm{\φ}}_{gun}^k{p}_{un}^k\left(u\right)$

${\hat{Q}}_{gu}^k(u,t)=\underset{n=1}{\overset{3}{\Σ}}{\hat{Q}}_{gun}^k{p}_{un}^k\left(u\right)---\left(19\right)$

$L_{gu}^k(u,t)=\underset{n=1}{\overset{3}{\Σ}}{L}_{gun}^k{p}_{un}^k\left(u\right)$

In formula:

$p_{u1}^k\left(u\right)=1$

$\begin{array}{cc}{p}_{u2}^k\left(u\right)=u/a_u^k& u\∈\[-a_u^k,a_u^k\]---\end{array}\left(20\right)$

$p_{u3}^k\left(u\right)=\frac{3}{2}{\left(\frac{u}{a_u^k}\right)}^2-\frac{1}{2}$

(19) are substituted into formula (11) to formula (17), net flow response matrix can be obtained. Adopting Weighted residue method, solve inclined neutron flux expansion coefficient, weighting function is as shown in (20) formula. The matrix form that inclined neutron flux solves is:

$\begin{array}{c}\{\[A_u\]+\frac{\[G_{g,u}^{uu,k}\]}{v_g{\mathrm{\Δt}}_j}\}{\underset{\‾}{\mathrm{\φ}}}_{{}^{gu}}^k\left(t\right)=\[G_{gu}^{uu,k}\]\{\widehat{\underset{\‾}{Q}}\left(t\right)-{\underset{\‾}{L}}_{gu}^k\left(t\right)+{\underset{\‾}{S}}_{gu}^k\left(t_0\right)\}\\ -{\underset{\‾}{G}}_{gu}^{+u,k}{J}_{gu}^k(a_u^k,t)+{\underset{\‾}{G}}_{gu}^{-u,k}{J}_{gu}^k(-a_u^k,t)\end{array}---\left(21\right)$

In formula, underscore represents 3 dimensional vectors.Sign expansion coefficient vector. WithIn like manner can obtain.WithCharacterize respectivelyWithLegendre expansion coefficient; [A_u] andBeing 3 �� 3 square formations, its coefficient meets:

${\left({\underset{\‾}{G}}_{gu}^{\±u,k}\right)}_n={\∫}_{-a_u^k}^{a_u^k}{\mathrm{duG}}_{gu}^k(u,\±a_u^k)p_{un}^k\left(u\right)---\left(22\right)$

${\[A_u\]}_{mn}=\underset{-a_u^k}{\overset{a_u^k}{\∫}}{p}_{u,m}^k\left(u\right)p_{u,n}^k\left(u\right)du---\left(23\right)$

${\[G_{gu}^{uu,k}\]}_{mn}=\underset{-a_u^k}{\overset{a_u^k}{\∫}}{p}_{u,m}^k\left(u\right)\underset{-a_u^k}{\overset{a_u^k}{\∫}}{p}_{u,n}^k\left(u_0\right)G_{gu}^k(u,u_0){\mathrm{du}}_{0}du---\left(24\right)$

2 rank approximation methods are adopted to solve the expansion coefficient of transverse leakage item. Assume that transverse leakage n-th-trem relation n formula is all set up in adjacent 3 locking nub, then can be obtained 3 equations by 3 locking nub average transverse leakages, to determine expansion coefficient. Coefficient expressions is:

$L_{gu1}^k={\stackrel{\‾}{L}}_{gu}^k$

$\begin{array}{c}{L}_{gu2}^k=\frac{a_u^k}{2d_u}\[(2a_u^{k-1}+a_u^k)\·(a_u^{k-1}+a_u^k)({\stackrel{\‾}{L}}_{gu}^{k+1}-{\stackrel{\‾}{L}}_{gu}^k)\\ +(a_u^k+a_u^{k+1})\·(a_u^k+2a_u^{k+1})({\stackrel{\‾}{L}}_{gu}^k-{\stackrel{\‾}{L}}_{gu}^{k-1})\]\end{array}---\left(25\right)$

$L_{gu3}^k=\frac{1}{2d_u}{\left(a_u^k\right)}^2\·\[(a_u^{k-1}+a_u^k)({\stackrel{\‾}{L}}_{gu}^{k+1}-{\stackrel{\‾}{L}}_{gu}^k)+(a_u^{k+1}+a_u^k)({\stackrel{\‾}{L}}_{gu}^{k-1}-{\stackrel{\‾}{L}}_{gu}^k)\]$

The average leaked of locking nub can be tried to achieve by clean neutron current:

$\begin{array}{c}{\stackrel{\‾}{L}}_{gu}^k=\frac{1}{2a_u^k}{\∫}_{-a_u^k}^{a_u^k}{L}_{gu}^k(u,t)du\\ =\frac{1}{2a_v^k}\[J_{gv}^k(a_v^k,t)-J_{gv}^k(-a_v^k,t)\]+\frac{1}{2a_w^k}\[J_{gw}^k(a_w^k,t)-J_{gw}^k(-a_w^k,t)\]\end{array}---\left(26\right)$

In formula,Sign average transverse leaks, $d_u=(a_u^{k-1}+a_u^k)(a_u^{k+1}+a_u^k)(a_u^{k-1}+a_u^k+a_u^{k+1}),$ Upper line represents locking nub body meansigma methods.

Net flow response matrix, neutron balance equation formula (18) and inclined Flux Expansion coefficient equation (21) that the fundamental equation solved based on the locking nub Green's function transient state of second kind boundary condition is made up of to formula (17) formula (11) are constituted, and source alternative manner can be adopted to solve.

Further, the time discrete method that the three-dimensional Neutron Time-Space Kinetics module of described execution reactor core Three dimensional transient physical computing adopts is Euler's method backward. Wherein, Euler's method possesses definitely-stability backward, and is easy to the coupled in series exploitation of program.

Wherein, adopt the instantaneous neutron calculation process of Euler's method backward, refer to Fig. 4, particularly as follows: first changed the correlative in a upper moment; It is ready for cross section; Then source item is updated; Then the average net flow in all directions interface is solved successively; Then node average flux and inclined neutron flux coefficient are solved; Then judge whether all group energys meet requirement, if being unsatisfactory for, returning and performing to update source item, if meeting, then judging whether fission source restrains, if not restraining, then return and perform to update source item, if convergence, update pioneer's nuclear concentration; Then subsequent time calculating is carried out.

Below in conjunction with drawings and Examples, the present invention is further detailed explanation.

The invention provides a kind of supercritical water reactor reactor core Three dimensional transient method for analyzing performance, apply the reactor core three-dimensional steady state-transient state physics-thermal-hydraulic coupling calculation process of analysis method of the present invention as shown in Figure 1, apply the stable state calculation process of analysis method of the present invention as shown in Figure 2, apply the transient state calculation process of analysis method of the present invention as shown in Figure 3, Fig. 1, Fig. 2, Fig. 3 simply show the present invention and propose a kind of embodiment of concept, and below in conjunction with Fig. 1, Fig. 2, Fig. 3 and detailed description of the invention, the invention will be further described:

As shown in Figure 1, supercritical water reactor reactor core three-dimensional steady state-transient state physics-thermal-hydraulic coupling calculation process includes (1) SCWR reactor core three-dimensional steady state physics-thermal-hydraulic coupling and calculates, (2) steady-state module transmits to transient state module data, (3) SCWR reactor core Three dimensional transient physics-thermal-hydraulic coupling calculates, (4) hot assembly subchannel thermal technology-water force, (5) five steps of key parameter safety evaluation, wherein, SCWR reactor core three-dimensional steady state physics-thermal-hydraulic coupling calculates (1) and includes in-core fuel management module calculating stable state reactor core and subchannel thermal technology-hydraulic module calculating two parts of stable state reactor core, steady-state module transmits, to transient state module data, the data (2) transmitted and includes initial core state and assembly cross-section library, SCWR reactor core Three dimensional transient physics-thermal-hydraulic coupling calculates (3) and includes three-dimensional Neutron Time-Space Kinetics module calculating transient state reactor core and subchannel thermal technology-hydraulic module calculating two parts of transient state reactor core, hot assembly subchannel thermal technology-water force (4) utilizes thermal technology's module, hot assembly after power is reconstructed carries out subchannel computational analysis, provide maximum involucrum wall surface temperature (MCST), key parameter safety evaluation (5) is by judging whether MCST exceedes corresponding transient state or fail-safe limit value, evaluate supercritical water reactor reactor core security performance under transient process.

As in figure 2 it is shown, in supercritical water reactor reactor core Three dimensional transient method for analyzing performance stable state calculation process, three-dimensional neutronics module and subchannel thermal technology's module carry out reactor core stable state calculating respectively, and perform iteration coupling and calculate until power convergence.

As it is shown on figure 3, in supercritical water reactor reactor core Three dimensional transient method for analyzing performance transient state calculation process, subchannel thermal technology's module and three-dimensional Neutron Time-Space Kinetics module carry out reactor core transient state calculating respectively, and perform iteration coupling and calculate until power convergence.

Above-mentioned supercritical water reactor reactor core Three dimensional transient method for analyzing performance, establish reactor core three-dimensional steady state-transient state physics-thermal-hydraulic coupling calculation process, can feedback between accurate description physics and thermal technology-waterpower, accurate reactor core three-dimensional power is provided to be distributed, it is achieved to simulate the transient process of supercritical water reactor and the purpose of accident process truly.

Give a concrete illustration below and be introduced:

Apply supercritical water reactor reactor core Three dimensional transient of the present invention and analyze method, analyze each transient problem under supercritical water reactor Hot zero power (HZP) and hot full power (HFP) state, to check Three dimensional transient to analyze the suitability of method. Problem reactor core is supercritical water reactor CSR1000 reactor core, reactor core initial power respectively 2300W and 2300MW under HZP and HFP state. Transient problem is bullet rod problem, and bullet rod position is ii flow component position E11. In HZP bullet rod problem, ejecting rod initial position is from being 7.7cm bottom active region, and in 0.1s, bullet is to final position 420cm. In HFP bullet rod problem, ejecting rod initial position is from being 210cm bottom active region, and in 0.1s, bullet is to final position 420cm. The ejecting rod of HZP and HFP problem is worth respectively 683pcm and 293pcm. Described Three dimensional transient is utilized to analyze method, CSR1000 reactor core three-dimensional steady state physics-thermal-hydraulic coupling module is first carried out and performs the calculating of reactor core stable state, in-core fuel management module provides power parameter to subchannel thermal technology-hydraulic module, subchannel thermal technology-hydraulic module provides thermal parameter to in-core fuel management module, performs iteration coupling and calculates until reactor core steady state power parameter and thermal parameter are restrained; Then reactor core three-dimensional steady state physics-thermal-hydraulic coupling module is utilized to provide reactor core original state and assembly cross-section library to reactor core Three dimensional transient physics-thermal-hydraulic coupling module; Then perform CSR1000 reactor core Three dimensional transient physics-thermal-hydraulic coupling module and perform transient state calculating, three-dimensional Neutron Time-Space Kinetics module provides power parameter to subchannel thermal technology-hydraulic module, subchannel thermal technology-hydraulic module provides thermal parameter to three-dimensional Neutron Time-Space Kinetics module, performs iteration coupling and calculates until reactor core transient power parameter and thermal parameter are restrained; Then in reactor core calculates, hot assembly is carried out power reconstruct and obtains the fine power distribution of hot assembly lattice cell yardstick, carry out hot assembly subchannel analysis again with thermal technology's module, finally provide safety evaluation key parameter-maximum involucrum wall surface temperature; Finally judge whether maximum involucrum wall surface temperature exceedes fail-safe limit value, evaluate CSR1000 reactor core security performance under rod ejection transient process. Three dimensional transient analysis is it is shown that the reactor core peak power of HZP bullet rod problem is 0.68NP (rated power 2300MW), and maximum involucrum wall surface temperature is 440 DEG C, lower than safety limit under accident conditions 1260 DEG C; The reactor core peak power of HFP bullet rod problem is 1.74NP, and maximum involucrum wall surface temperature is 1075 DEG C, lower than safety limit under accident conditions 1260 DEG C. The Three dimensional transient analysis of CSR1000 reactor core bullet rod problem being shown, no matter is HFP bullet rod or HZP bullet rod, in accident process, maximum involucrum wall surface temperature peak value is below fail-safe limit value 1260 DEG C, meets safety requirements.

Technical scheme in above-mentioned the embodiment of the present application, at least has the following technical effect that or advantage:

Include owing to have employed to be designed as supercritical water reactor reactor core Three dimensional transient method for analyzing performance: step 1: supercritical water reactor reactor core three-dimensional steady state physics-thermal-hydraulic coupling module performs reactor core stable state and calculates, in-core fuel management module provides power parameter to subchannel thermal technology-hydraulic module, subchannel thermal technology-hydraulic module provides thermal parameter to in-core fuel management module, performs iteration coupling and calculates until reactor core steady state power parameter and thermal parameter are restrained;Step 2: reactor core three-dimensional steady state physics-thermal-hydraulic coupling module provides reactor core original state and assembly cross-section library to supercritical water reactor reactor core Three dimensional transient physics-thermal-hydraulic coupling module; Step 3: supercritical water reactor reactor core Three dimensional transient physics-thermal-hydraulic coupling module performs transient state and calculates, three-dimensional Neutron Time-Space Kinetics module provides power parameter to subchannel thermal technology-hydraulic module, subchannel thermal technology-hydraulic module provides thermal parameter to three-dimensional Neutron Time-Space Kinetics module, performs iteration coupling and calculates until reactor core transient power parameter and thermal parameter are restrained; Step 4: in reactor core calculates, hot assembly is carried out power reconstruct and obtains the fine power distribution of hot assembly lattice cell yardstick, carry out hot assembly subchannel analysis again with thermal technology's module, finally provide safety evaluation key parameter; Step 5: judge whether described safety evaluation key parameter exceedes corresponding transient state or fail-safe limit value, evaluate the technical scheme of supercritical water reactor reactor core security performance under transient process, namely Analysis of Transient is carried out by the three-dimensional Neutron Time-Space Kinetics of coupling with thermal technology-hydraulics, neutron dynamics part adopts threedimensional model, it is made to possess the three-dimensional power calculation ability of reactor core nuclear heat coupling, it is achieved the technique effect that supercritical water reactor reactor core Three dimensional transient is analyzed; So, efficiently solve the distribution transient state analyzing method existence of existing supercritical water reactor power and do not possess the three-dimensional power calculation ability of reactor core nuclear heat coupling, it is difficult to truly or accurately simulate the technical problem of the such as transient process of reactivity and power abnormal distribution event, achieve by setting up reactor core three-dimensional steady state-transient state physics-thermal-hydraulic coupling calculation process, can feedback between accurate description physics and thermal technology-waterpower, there is provided more accurate reactor core three-dimensional power to be distributed, simulate the transient process of supercritical water reactor and the technique effect of accident process truly.

Further, this method can simulate supercritical water reactor reactor core transient process truly, improves the understanding to supercritical water reactor reactor core transient condition, estimates safety allowance more accurately, improve Core Design and improve heap core performance.

Although preferred embodiments of the present invention have been described, but those skilled in the art are once know basic creative concept, then these embodiments can be made other change and amendment. So, claims are intended to be construed to include preferred embodiment and fall into all changes and the amendment of the scope of the invention.

Obviously, the present invention can be carried out various change and modification without deviating from the spirit and scope of the present invention by those skilled in the art. So, if these amendments of the present invention and modification belong within the scope of the claims in the present invention and equivalent technologies thereof, then the present invention is also intended to comprise these change and modification.

Claims (7)

1. a supercritical water reactor reactor core Three dimensional transient method for analyzing performance, it is characterised in that described method includes:

Step 1: supercritical water reactor reactor core three-dimensional steady state physics-thermal-hydraulic coupling module performs reactor core stable state and calculates, in-core fuel management module provides power parameter to subchannel thermal technology-hydraulic module, subchannel thermal technology-hydraulic module provides thermal parameter to in-core fuel management module, performs iteration coupling and calculates until reactor core steady state power parameter and thermal parameter are restrained;

Step 2: reactor core three-dimensional steady state physics-thermal-hydraulic coupling module provides reactor core original state and assembly cross-section library to supercritical water reactor reactor core Three dimensional transient physics-thermal-hydraulic coupling module;

Step 3: supercritical water reactor reactor core Three dimensional transient physics-thermal-hydraulic coupling module performs transient state and calculates, three-dimensional Neutron Time-Space Kinetics module provides power parameter to subchannel thermal technology-hydraulic module, subchannel thermal technology-hydraulic module provides thermal parameter to three-dimensional Neutron Time-Space Kinetics module, performs iteration coupling and calculates until reactor core transient power parameter and thermal parameter are restrained;

Step 4: in reactor core calculates, hot assembly is carried out power reconstruct and obtains the fine power distribution of hot assembly lattice cell yardstick, carry out hot assembly subchannel analysis again with subchannel thermal technology-hydraulic module, finally provide safety evaluation key parameter;

Step 5: judge whether described safety evaluation key parameter exceedes corresponding transient state or fail-safe limit value, evaluates supercritical water reactor reactor core security performance under transient process.

2. method according to claim 1, it is characterised in that described safety evaluation key parameter includes: maximum involucrum wall surface temperature, pellet heat content.

3. method according to claim 1, it is characterized in that, reactor core three-dimensional Neutronics calculation uses few group cross-section, few group cross-section adopts the mode of piecewise interpolation to be processed into cross-section library in advance for reactor core three-dimensional neutronics module about the change of thermal parameter and parameter preset, and described parameter preset includes: fuel-assembly burn-up, with or without control rod.

4. method according to claim 1, it is characterised in that the coupling of described execution iteration calculates until reactor core steady state power parameter and thermal parameter convergence specifically include:

Start;

Read input file, initialization component few group cross-section, reactor core neutron flux;

Carry out subchannel thermal technology's module stable state to calculate;

It is updated cross section;

Carry out three-dimensional neutronics module stable state to calculate;

Carry out subchannel thermal technology's module stable state to calculate;

Judge whether core power distribution restrains, then return step if not and re-start renewal cross section; If then stable state calculates and terminates, enter transient state and calculate.

5. method according to claim 1, it is characterised in that described supercritical water reactor reactor core Three dimensional transient physics-thermal-hydraulic coupling module performs transient state calculating and specifically includes:

Start transient state to calculate;

Carry out time step renewal, prepare the initial value in n moment;

Carry out subchannel thermal technology's module transient state and calculate a time step;

It is updated cross section;

Carry out three-dimensional Neutron Time-Space Kinetics module transient state and calculate first time step;

Judge whether core power distribution restrains, then return if not and perform time step renewal, prepare the initial value in n moment; If then n=n+1; Judging that whether tn is less than T, wherein, tn was the n-th time step correspondence time, and T is that preassigned transient state calculated to the T moment, performing time step renewal if then returning, preparing the initial value in n moment; Then calculate if not and terminate.

6. method according to claim 1, it is characterized in that, described supercritical water reactor reactor core three-dimensional steady state physics-thermal-hydraulic coupling module performs reactor core stable state and calculates and described supercritical water reactor reactor core Three dimensional transient physics-thermal-hydraulic coupling module execution transient state calculating, all adopts identical space method for solving: second kind boundary condition locking nub green function method.

7. method according to claim 1, it is characterised in that the time discrete method that described three-dimensional Neutron Time-Space Kinetics module adopts is: Euler's method backward.