Critical heat flux prediction device, critical heat flux prediction method and safety evaluation system
AssigneeMitsubishi Heavy Industries, Ltd.
InventorTadakatsu Yodo
Life of this patent
Estimating the term…
Abstract
A critical heat flux prediction device, a critical heat flux prediction method, a safety evaluation system, and a core monitoring system using the safety evaluation system can predict critical heat flux in a core of a reactor with a high degree of accuracy by obtaining a correlation plot distribution representing a relation of critical heat flux on a thermal equilibrium quality based on experimental data, approximating a correlation plot distribution through a logistic function that is a model function in which critical heat flux is expressed by a function of a thermal equilibrium quality, and obtaining a critical heat flux correlation of critical heat flux and a thermal equilibrium quality.
Claims2
A real core shape simulation fuel experiment method for acquiring experimental data by a simulation of a real reactor comprising:
- filing an experimental vessel with a coolant;
- arranging a simulation fuel rod so as to be covered with the coolant in the experimental vessel;
- heating the simulation fuel rod;
- measuring, as measurement data, critical heat flux, a surface temperature of a fuel rod, a mass velocity, and a temperature of the coolant, and outputting as output signals, the measurement data and a thermal equilibrium quality determined from the measurement data;
- and
- predicting critical heat flux for the simulation fuel rod, wherein
- the predicting the critical heat flux includes:
- storing the output signals as experimental data into a storage unit;
- reading the experimental data from the storage unit;
- plotting the experimental data so as to obtain a correlation plot distribution;
- loading a logistic function from the storage unit wherein the logistic function is Formula (1):
- q
- ″
- =
- A
- 1
- +
- exp
-
- (
- -
- K
-
- (
- (
- 1
- -
- x
- )
- -
- C
- )
- )
- (
- 1
- )
- where q″ is critical heat flux, x is the thermal equilibrium quality, and A, K, and C are coefficients;
- calculating the coefficients A, K, and C such that the correlation plot distribution Z is approximated by the logistic function;
- obtaining a critical heat flux correlation by inputting the coefficients A, K, and C to the logistic function and obtaining a curve of the critical heat flux correlation;
- comparing the curve of the critical heat flux correlation with the correlation plot distribution;
- outputting, as an output data, the critical heat flux correlation when the curve of the critical heat flux correlation and the correlation plot distribution are within a predetermined allowable range;
- displaying the output critical heat flux correlation on a display unit;
- wherein the thermal equilibrium quality x is expressed as
- x
- =
- h
- g
- -
- h
- Isat
- h
- fg
-
-
- h
- g
- :
- enthalpy
-
-
- of
-
-
- coolant
-
-
- J
-
- /
-
- kg
-
-
- h
- Isat
- :
- enthalpy
-
-
- of
-
-
- saturated
-
-
- water
-
-
- J
-
- /
-
- kg
-
-
- h
- fg
- :
- latent
-
-
- heat
-
-
- J
-
- /
-
- kg
- .
- (
- 2
- )
Dependencies are inferred from the claim text.