Calculation Method and Device for Helium Leakage Rate in the Primary Circuit of a High-Temperature Gas-Cooled Reactor

Abstract

An embodiment of the present disclosure provides a method and device for calculating the helium leakage rate of the primary circuit of a high-temperature gas-cooled reactor. The method includes: determining calculation parameters; calculating the helium density at the inlet of the main helium blower according to the differential pressure of the flowmeter at the inlet elbow of the main helium blower, the volume flow rate at the inlet elbow of the main helium blower, and the dimensions of the inlet elbow of the main helium blower; converting the helium density at the inlet of the main helium blower to the standard density under standard conditions according to the pressure and temperature of the current operating condition; calculating the helium leakage rate of the primary circuit during the calculation period according to the helium density converted to the standard conditions at the initial moment of calculation and the helium density converted to the standard conditions at the end moment of calculation. All calculation parameters are directly read by instruments, and the helium leakage rate of the primary circuit is directly calculated through the change in density, with high calculation accuracy and simplicity; in addition, this calculation method uses the original equipment and measuring points of the high-temperature gas-cooled reactor without additional investment.

Description

Technical Field

[0001] The present disclosure belongs to the technical field of high-temperature reactors, and particularly relates to a method and device for calculating the helium leakage rate of the primary circuit of a high-temperature gas-cooled reactor. Background Art

[0002] The high-temperature gas-cooled reactor uses helium as the primary coolant. Helium is an inert gas with good heat transfer and heat-carrying characteristics. However, its penetration ability is much stronger than that of ordinary gases, and it is very easy to leak outside the primary circuit pressure boundary of the reactor through connecting flanges, etc. Helium leakage can cause radioactive contamination at least, and can lead to loss of cooling and pressure in the high-temperature gas-cooled reactor, resulting in reactivity accidents at worst.

[0003] Currently, during the operation of high-temperature gas-cooled reactors, the helium leakage rate is determined according to the change in the total helium inventory in the relevant systems of the primary circuit at different times. However, in this method, the temperature distribution in each partition of the primary circuit is approximately calculated through a limited number of temperature instruments, and the volume of the relevant part of the primary circuit uses design data, which may have a certain deviation from the actual situation, reducing the accuracy of the calculation method. Summary of the Invention

[0004] The present disclosure aims to solve at least one of the technical problems existing in the prior art, and provides a method and device for calculating the helium leakage rate of the primary circuit of a high-temperature gas-cooled reactor.

[0005] In a first aspect, the present disclosure provides a method for calculating the helium leakage rate of the primary circuit of a high-temperature gas-cooled reactor, the method comprising:

[0006] Determine calculation parameters; wherein, the calculation parameters include: the differential pressure of the elbow flowmeter at the inlet of the main helium blower, the rotational speed of the main helium blower, the inlet pressure of the main helium blower, and the helium temperature at the inlet of the main helium blower;

[0007] Calculate the helium density at the inlet of the main helium blower according to the differential pressure of the elbow flowmeter at the inlet of the main helium blower, the volume flow rate at the inlet of the main helium blower elbow, and the dimensions of the elbow at the inlet of the main helium blower;

[0008] Convert the helium density at the inlet of the main helium blower to the density under standard conditions according to the pressure and temperature of the current operating condition;

[0009] Calculate the helium leakage rate of the primary circuit during the calculation period according to the helium density converted to the standard condition at the initial moment of calculation and the helium density converted to the standard condition at the end moment of calculation.

[0010] In some embodiments, the helium density at the inlet of the main helium blower is calculated according to the following relational expression (1):

[0011]

[0012] Wherein, ρ is the helium density at the inlet of the main helium blower, ΔP is the differential pressure of the elbow flowmeter at the inlet of the main helium blower, Q is the volumetric flow rate of the elbow at the inlet of the main helium blower, C is a function of R and D, R is the center curvature radius of the elbow at the inlet of the main helium blower, and D is the inner diameter of the elbow at the inlet of the main helium blower.

[0013] In some embodiments, the helium density at the inlet of the main helium blower is converted to the density under standard conditions according to the following relational formula (2):

[0014]

[0015] Wherein, ρ N , P N and T N are the helium density, pressure, and temperature under standard conditions respectively; P and T are the helium pressure and temperature under actual conditions respectively.

[0016] In some embodiments, the primary loop helium leakage rate during the calculation period is obtained according to the following relational formulas (3) to (5):

[0017]

[0018] Substituting the relational formula (2) into the relational formula (3), we get:

[0019]

[0020] The main helium blower is a centrifugal blower, and its volumetric flow rate is proportional to the rotational speed. Therefore, the calculation formula for the primary loop leakage rate during the calculation period is finally expressed by the following relational formula (5):

[0021]

[0022] Wherein, L is the primary loop helium leakage rate during the calculation period, ρ1 is the helium density converted to the standard condition at the initial moment of calculation, and ρ2 is the helium density converted to the standard condition at the end moment of calculation;

[0023] ΔP1, P1, T1, Q1, and n1 are the differential pressure of the elbow flowmeter, the inlet pressure of the main helium blower, the inlet temperature of the main helium blower, the volumetric flow rate of the primary loop helium, and the rotational speed of the main helium blower at the initial moment of calculation respectively;

[0024] ΔP2, P2, T2, Q2, and n2 are the differential pressure of the elbow flowmeter, the inlet pressure of the main helium blower, the inlet temperature of the main helium blower, the volumetric flow rate of the primary loop helium, and the rotational speed of the main helium blower at the end moment of calculation respectively.

[0025] In some embodiments, the method further includes: calculating the primary loop helium leakage rate within one day according to the primary loop helium leakage rate during the calculation period.

[0026] In some embodiments, the primary circuit helium leakage rate within one day is calculated according to the following relational expression (6):

[0027]

[0028] where L 天 is the primary circuit helium leakage rate within one day, and α is the ratio of one day's time to the calculation period.

[0029] In a second aspect, the present disclosure provides a calculation device for the primary circuit helium leakage rate of a high-temperature gas-cooled reactor, and the device includes:

[0030] a determination module, configured to determine calculation parameters; wherein, the calculation parameters include: differential pressure of the flowmeter at the inlet elbow of the main helium blower, rotational speed of the main helium blower, inlet pressure of the main helium blower, and inlet helium temperature of the main helium blower;

[0031] a calculation module, configured to calculate the inlet helium density of the main helium blower according to the differential pressure of the flowmeter at the inlet elbow of the main helium blower, the volume flow rate at the inlet elbow of the main helium blower, and the dimensions of the inlet elbow of the main helium blower;

[0032] a conversion module, configured to convert the inlet helium density of the main helium blower into the density under standard conditions according to the pressure and temperature of the current operating condition;

[0033] The calculation module is further configured to calculate the primary circuit helium leakage rate during the calculation period according to the helium density converted to the standard condition at the initial moment of calculation and the helium density converted to the standard condition at the end moment of calculation.

[0034] In some embodiments, the calculation module is configured to calculate the inlet helium density of the main helium blower according to the following relational expression (1):

[0035]

[0036] where ρ is the inlet helium density of the main helium blower, ΔP is the differential pressure of the flowmeter at the inlet elbow of the main helium blower, Q is the volume flow rate at the inlet elbow of the main helium blower, C is a function of R and D, R is the center curvature radius of the inlet elbow of the main helium blower, and D is the inner diameter of the inlet elbow of the main helium blower.

[0037] In some embodiments, the conversion module is configured to convert the inlet helium density of the main helium blower into the density under standard conditions according to the following relational expression (2):

[0038]

[0039] where ρ N , P N and T Nare the helium density, pressure, and temperature under standard conditions, respectively; P and T are the helium pressure and temperature under actual conditions, respectively.

[0040] In some embodiments, the calculation module is further configured to calculate the primary loop helium leakage rate during a calculation period according to the following relational expressions (3) to (5):

[0041]

[0042] Substitute the relational expression (2) into the relational expression (3) to obtain:

[0043]

[0044] The main helium blower is a centrifugal blower, and its volume flow rate is proportional to the rotational speed. Then, the calculation formula for the primary loop leakage rate during the calculation period is finally expressed by the following relational expression (5):

[0045]

[0046] where L is the primary loop helium leakage rate during the calculation period, ρ1 is the helium density converted to the standard condition at the initial moment of calculation, and ρ2 is the helium density converted to the standard condition at the end moment of calculation;

[0047] ΔP1, P1, T1, Q1, and n1 are the differential pressure of the elbow flowmeter, the inlet pressure of the main helium blower, the inlet temperature of the main helium blower, the volume flow rate of the primary loop helium gas, and the rotational speed of the main helium blower at the initial moment of calculation, respectively;

[0048] ΔP2, P2, T2, Q2, and n2 are the differential pressure of the elbow flowmeter, the inlet pressure of the main helium blower, the inlet temperature of the main helium blower, the volume flow rate of the primary loop helium gas, and the rotational speed of the main helium blower at the end moment of calculation, respectively.

[0049] For the calculation method and device of the primary loop helium leakage rate of the high-temperature gas-cooled reactor in the embodiments of the present disclosure, all calculation parameters are directly read by instruments, and the primary loop helium leakage rate is directly calculated through the change in density, with high calculation accuracy and simplicity; in addition, this calculation method uses the original equipment and measuring points of the high-temperature gas-cooled reactor without additional investment. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 is a flowchart of an embodiment of the calculation method of the primary loop helium leakage rate of the high-temperature gas-cooled reactor according to the present disclosure;

[0051] Figure 2 is a schematic structural diagram of an embodiment of the calculation device of the primary loop helium leakage rate of the high-temperature gas-cooled reactor according to the present disclosure. DETAILED DESCRIPTION

[0052] To enable those skilled in the art to better understand the technical solutions of the present disclosure, the present disclosure will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0053] The present disclosure provides a method for calculating the helium leakage rate of the primary circuit of a high-temperature gas-cooled reactor. Figure 1 Shown is a flow 100 of an embodiment of the method for calculating the helium leakage rate of the primary circuit of a high-temperature gas-cooled reactor according to the present disclosure. The flow 100 includes the following specific steps:

[0054] Step 110, determine calculation parameters; wherein, the calculation parameters include: the differential pressure of the elbow flowmeter at the inlet of the main helium blower, the rotational speed of the main helium blower, the inlet pressure of the main helium blower, and the helium temperature at the inlet of the main helium blower.

[0055] Specifically, in this step, parameters such as the differential pressure ΔP of the elbow flowmeter at the inlet of the main helium blower, the rotational speed n of the main helium blower, the inlet pressure P of the main helium blower, and the helium temperature T at the inlet of the main helium blower are selected for subsequent calculation of the helium leakage rate of the primary circuit. In this step, the acquisition of these parameters can all be directly obtained through instrument measurement. For example, the above-mentioned parameters can be respectively obtained through a flowmeter, a rotational speed sensor, a pressure sensor, and a temperature sensor provided on the main helium blower.

[0056] Step 120, calculate the helium density at the inlet of the main helium blower according to the differential pressure of the elbow flowmeter at the inlet of the main helium blower, the volume flow at the inlet of the main helium blower elbow, and the dimensions of the elbow at the inlet of the main helium blower.

[0057] Specifically, in this step, the flow measurement formula of the elbow flowmeter at the inlet of the main helium blower is as follows formula (1):

[0058]

[0059] In the formula, Q is the volume flow, C is a function of R and D, R is the radius of curvature of the elbow center, D is the inner diameter of the elbow, ΔP is the differential pressure of the elbow flowmeter at the inlet of the main helium blower, and ρ is the helium density.

[0060] According to the above formula (1), the calculation formula for the helium density at the inlet of the main helium blower can be obtained as follows formula (2):

[0061]

[0062] For the main helium blower, R and D are determined values, so C is a fixed value. Therefore, the parameters affecting the helium density are ΔP and Q.

[0063] Step 130, convert the helium density at the inlet of the main helium blower to the density under standard conditions according to the pressure and temperature of the current operating condition.

[0064] Specifically, in this step, the helium density at the inlet of the main helium blower is converted to the density under standard conditions according to the following formula (3):

[0065]

[0066] In the formula, ρ N , P N , T N are respectively the helium density, pressure, and temperature under standard conditions. ρ, P, T, and ΔP are respectively the helium density, pressure, temperature, and differential pressure of the elbow flowmeter under actual conditions.

[0067] Step 140: Calculate the primary loop helium leakage rate during the calculation period based on the helium density converted to the standard condition at the initial moment of calculation and the helium density converted to the standard condition at the end moment of calculation.

[0068] Specifically, in this step, determine the calculation reference formula for the primary loop helium leakage rate. Under the same working conditions, i.e., standard conditions, compare the change in helium density during the calculation period to obtain the helium leakage rate. The formula is as follows (4):

[0069]

[0070] In the formula, L is the primary loop helium leakage rate during the calculation period. ρ1 is the helium density converted to the standard condition at the initial moment of calculation, and ρ2 is the helium density converted to the standard condition at the end moment of calculation.

[0071] Furthermore, substitute the above formula (3) into formula (4) to obtain the calculation formula for the primary loop leakage rate, as follows (5):

[0072]

[0073] The main helium blower is a centrifugal blower, and its volume flow rate is proportional to the rotational speed. Then, the calculation formula for the primary loop leakage rate during the calculation period can finally be expressed by the following formula (6):

[0074]

[0075] In the formula, ΔP1, P1, T1, Q1, and n1 are respectively the differential pressure of the elbow flowmeter, the inlet pressure of the main helium blower, the inlet temperature of the main helium blower, the volume flow rate of helium in the primary loop, and the rotational speed of the main helium blower at the initial moment of calculation. ΔP2, P2, T2, Q2, and n2 are respectively the differential pressure of the elbow flowmeter, the inlet pressure of the main helium blower, the inlet temperature of the main helium blower, the volume flow rate of helium in the primary loop, and the rotational speed of the main helium blower at the end moment of calculation.

[0076] The calculation method for the primary circuit helium leakage rate of the high-temperature gas-cooled reactor in this embodiment has all calculation parameters directly read by instruments, and directly calculates the primary circuit helium leakage rate through the change in density, with high calculation accuracy, simplicity and feasibility; in addition, this calculation method uses the original equipment and measuring points of the high-temperature gas-cooled reactor without additional investment.

[0077] In some embodiments, such as Figure 1 shown, the method further includes: Step 150, calculating the primary circuit helium leakage rate within one day based on the primary circuit helium leakage rate within the calculation period.

[0078] In some embodiments, the primary circuit helium leakage rate within one day is calculated according to the following relational expression (7):

[0079]

[0080] wherein, L 天 is the primary circuit helium leakage rate within one day, and α is the ratio of one day's time to the calculation period.

[0081] As Figure 2 shown, the present disclosure also provides a calculation device 200 for the primary circuit helium leakage rate of a high-temperature gas-cooled reactor. This device 200 is applicable to the calculation method described above. For specific details, reference can be made to the relevant descriptions above and will not be elaborated here. The device 200 includes:

[0082] A determination module 210, configured to determine calculation parameters; wherein, the calculation parameters include: the differential pressure of the flowmeter at the inlet elbow of the main helium blower, the rotational speed of the main helium blower, the inlet pressure of the main helium blower, and the inlet helium temperature of the main helium blower.

[0083] A calculation module 220, configured to calculate the inlet helium density of the main helium blower according to the differential pressure of the flowmeter at the inlet elbow of the main helium blower, the volumetric flow rate at the inlet elbow of the main helium blower, and the dimensions of the inlet elbow of the main helium blower.

[0084] A conversion module 230, configured to convert the inlet helium density of the main helium blower into the density under standard conditions according to the pressure and temperature of the current operating condition.

[0085] The calculation module 220 is further configured to calculate the primary circuit helium leakage rate within the calculation period according to the helium density converted to the standard condition at the initial moment of calculation and the helium density converted to the standard condition at the end moment of calculation.

[0086] The calculation device for the primary circuit helium leakage rate of the high-temperature gas-cooled reactor in this embodiment has all calculation parameters directly read by instruments, and directly calculates the primary circuit helium leakage rate through the change in density, with high calculation accuracy, simplicity and feasibility; in addition, this calculation method uses the original equipment and measuring points of the high-temperature gas-cooled reactor without additional investment.

[0087] It is understood that the above embodiments are merely exemplary embodiments adopted to illustrate the principles of the present disclosure. However, the present disclosure is not limited thereto. For those of ordinary skill in the art, various modifications and improvements can be made without departing from the spirit and essence of the present disclosure, and these modifications and improvements are also regarded as the protection scope of the present disclosure.

Claims

1. A calculation method for the helium leakage rate of the primary circuit of a high-temperature gas-cooled reactor, characterized in that, The method includes: Determining calculation parameters; wherein, the calculation parameters include: the differential pressure of the main helium blower inlet elbow flowmeter, the rotational speed of the main helium blower, the inlet pressure of the main helium blower, and the inlet helium temperature of the main helium blower; Calculating the inlet helium density of the main helium blower based on the differential pressure of the main helium blower inlet elbow flowmeter, the inlet elbow volume flow rate of the main helium blower, and the dimensions of the main helium blower inlet elbow; Converting the inlet helium density of the main helium blower to the density under standard conditions according to the pressure and temperature of the current operating condition; Calculating the primary circuit helium leakage rate during the calculation period based on the helium density converted to standard conditions at the initial moment of calculation and the helium density converted to standard conditions at the end moment of calculation; 2. The method according to claim 1, wherein Calculating the inlet helium density of the main helium blower according to the following relational expression (1): where ρ is the inlet helium density of the main helium blower, ΔP is the differential pressure of the main helium blower inlet elbow flowmeter, Q is the inlet elbow volume flow rate of the main helium blower, C is a function of R and D, R is the center curvature radius of the main helium blower inlet elbow, and D is the inner diameter of the main helium blower inlet elbow.

3. The method according to claim 2, wherein Converting the inlet helium density of the main helium blower to the density under standard conditions according to the following relational expression (2): Among them, ρ N , P N and T N are the helium density, pressure, and temperature under standard conditions, respectively; P and T are the helium pressure and temperature under actual conditions, respectively.

4. The method according to claim 3, wherein Obtaining the primary circuit helium leakage rate during the calculation period according to the following relational expressions (3) to (5): Substituting the relational expression (2) into the relational expression (3), we get: The main helium blower is a centrifugal blower, and its volume flow rate is proportional to the rotational speed. Then, the calculation formula for the primary circuit leakage rate during the calculation period is finally expressed by the following relational expression (5): where L is the primary circuit helium leakage rate during the calculation period, ρ1 is the helium density converted to standard conditions at the initial moment of calculation, and ρ2 is the helium density converted to standard conditions at the end moment of calculation; ΔP1, P1, T1, Q1, and n1 are respectively the differential pressure of the elbow flowmeter, the inlet pressure of the main helium blower, the inlet temperature of the main helium blower, the volume flow rate of the primary circuit helium, and the rotational speed of the main helium blower at the initial moment of calculation; ΔP2, P2, T2, Q2, and n2 are respectively the differential pressure of the elbow flowmeter, the inlet pressure of the main helium blower, the inlet temperature of the main helium blower, the volume flow rate of the primary circuit helium, and the rotational speed of the main helium blower at the end moment of calculation.

5. The method according to claim 4, wherein The method further includes: calculating the primary circuit helium leakage rate within one day according to the primary circuit helium leakage rate during the calculation period.

6. The method according to claim 5, characterized in that, Calculating the primary circuit helium leakage rate within one day according to the following relational expression (6): Among them, L 天 is the primary circuit helium leakage rate within one day, and α is the ratio of one day's time to the said calculation period.

7. A calculation device for the helium leakage rate of the primary circuit of a high-temperature gas-cooled reactor, characterized in that, The device includes: A determination module for determining calculation parameters; wherein, the calculation parameters include: the differential pressure of the main helium blower inlet elbow flowmeter, the rotational speed of the main helium blower, the inlet pressure of the main helium blower, and the inlet helium temperature of the main helium blower; A calculation module for calculating the inlet helium density of the main helium blower based on the differential pressure of the main helium blower inlet elbow flowmeter, the inlet elbow volume flow rate of the main helium blower, and the dimensions of the main helium blower inlet elbow; A conversion module for converting the inlet helium density of the main helium blower to the density under standard conditions according to the pressure and temperature of the current operating condition; The calculation module is further configured to calculate the primary loop helium leakage rate during the calculation period according to the helium density converted to the standard working condition at the initial moment of calculation and the helium density converted to the standard working condition at the end moment of calculation.

8. The device according to claim 7, wherein The calculation module is configured to calculate the helium density at the inlet of the main helium blower according to the following relational expression (1): where ρ is the helium density at the inlet of the main helium blower, ΔP is the differential pressure of the elbow flowmeter at the inlet of the main helium blower, Q is the volume flow rate of the elbow at the inlet of the main helium blower, C is a function of R and D, R is the central curvature radius of the elbow at the inlet of the main helium blower, and D is the inner diameter of the elbow at the inlet of the main helium blower.

9. The device according to claim 8, characterized in that, The conversion module is configured to convert the helium density at the inlet of the main helium blower to the density under the standard working condition according to the following relational expression (2): where ρ N , P N and T N are the density, pressure, and temperature of helium under standard conditions, respectively; P and T are the pressure and temperature of helium under actual conditions, respectively.

10. The device according to claim 9, characterized in that, The calculation module is further configured to calculate the primary loop helium leakage rate during the calculation period according to the following relational expressions (3) to (5): Substituting the relational expression (2) into the relational expression (3), we get: The main helium blower is a centrifugal blower, and its volume flow rate is proportional to the rotational speed. Therefore, the calculation formula for the primary loop leakage rate during the calculation period is finally expressed by the following relational expression (5): where L is the primary loop helium leakage rate during the calculation period, ρ1 is the helium density converted to the standard working condition at the initial moment of calculation, and ρ2 is the helium density converted to the standard working condition at the end moment of calculation; ΔP1, P1, T1, Q1, and n1 are the differential pressure of the elbow flowmeter, the inlet pressure of the main helium blower, the inlet temperature of the main helium blower, the volume flow rate of the primary loop helium, and the rotational speed of the main helium blower at the initial moment of calculation, respectively; ΔP2, P2, T2, Q2, and n2 are the differential pressure of the elbow flowmeter, the inlet pressure of the main helium blower, the inlet temperature of the main helium blower, the volume flow rate of the primary loop helium, and the rotational speed of the main helium blower at the end moment of calculation, respectively.

Images