CN-122016169-A - Small-aperture leakage working condition simulation and risk assessment device in fuel cabin of gas turbine

CN122016169ACN 122016169 ACN122016169 ACN 122016169ACN-122016169-A

Abstract

The invention relates to the technical field of safety monitoring and risk assessment of gas turbines, in particular to a device for simulating and assessing the small-aperture leakage working condition in a fuel cabin of a gas turbine. The technical scheme includes that the fuel tank three-dimensional model building system comprises a model building module, a transient simulation module, a diffusion characteristic identification module, a multi-time assessment module and a risk level judgment module, wherein the model building module is used for building a fuel tank three-dimensional model and setting a small-aperture leakage source, the transient simulation module is used for acquiring fuel gas quality score distribution in a fuel gas leakage diffusion process, the diffusion characteristic identification module is used for identifying high-speed jet flow, top enrichment and wall surface diffusion characteristics, the multi-time assessment module is used for comparing fuel gas quality scores at different positions with alarm thresholds, and the risk level judgment module is used for outputting corresponding risk levels based on comparison results. The invention realizes the rapid simulation and risk classification evaluation of the gas small-aperture leakage working condition in the fuel cabin, and provides basis for safety monitoring and protection.

Inventors

PU HONGWEI
WANG WENYI
XU XIANG
LU LUN
ZHU ZIMING
JIANG KAI

Assignees

华能南京燃机发电有限公司

Dates

Publication Date: 20260512
Application Date: 20260205

Claims (9)

1. The utility model provides a gas turbine fuel cabin internal aperture leaks operating mode simulation and risk assessment device which characterized in that includes: the model construction module is used for constructing a three-dimensional space model of the fuel cabin of the gas turbine, and arranging a small-aperture gas leakage source facing the top of the fuel cabin in the space model; The transient simulation module is used for carrying out transient numerical simulation on the diffusion process after gas leakage to obtain gas mass fraction distribution along the preset X direction and Y direction in the fuel cabin at different moments; The diffusion characteristic recognition module is used for recognizing diffusion characteristics of the gas which is diffused along the periphery of the inner wall of the fuel cabin after being leaked to form high-speed jet flow and be sprayed to the top of the fuel cabin based on the mass fraction distribution of the gas; The multi-moment evaluation module is used for comparing the gas mass fractions at different space positions in the fuel cabin with an alarm threshold value at the moments at least comprising 2.5s, 5s, 7.5s and 50 s; And the risk level judging module is used for outputting the risk level of gas leakage in the fuel cabin according to the comparison result of the multi-time evaluation module.
2. The small-aperture leakage working condition simulation and risk assessment device in a gas turbine fuel cabin is characterized in that the model construction module comprises a fuel cabin geometric modeling unit and a leakage source parameter setting unit, wherein the leakage source parameter setting unit is used for setting the leakage aperture to be small and the leakage direction to be vertical upwards, and a three-dimensional space model constructed by the fuel cabin geometric modeling unit comprises a blowing pipeline outlet and inlet and a shutter which are communicated with the outside.
3. The small-aperture leakage working condition simulation and risk assessment device in a gas turbine fuel cabin according to claim 1 is characterized in that the transient simulation module comprises a time step control unit and a multi-time data acquisition unit, wherein the time step control unit is used for controlling the simulation time step to be not more than 0.1s so as to capture rapid jet flow dynamics at the initial stage of leakage, and the multi-time data acquisition unit is used for extracting a plurality of gas quality fractional fields corresponding to the moments and particularly acquiring distribution data in the X direction and the Y direction.
4. The small-aperture leakage working condition simulation and risk assessment device in a gas turbine fuel cabin is characterized in that the diffusion characteristic recognition module comprises a jet recognition unit, a top enrichment recognition unit and a wall diffusion recognition unit, wherein the top enrichment recognition unit is used for recognizing that the mass fraction of gas in a region right above a leakage port is larger than the maximum value of a high alarm threshold value of 0.022 at the early stage of leakage, the wall diffusion recognition unit is used for recognizing that the gas firstly diffuses transversely along the top wall and then diffuses downwards along the side wall, and recognizing that the gas diffuses outwards from the cabin through an outlet and an inlet of a purge pipe in the diffusion process, and the maximum value of the high alarm threshold value of 0.022 is obtained based on the conversion of the lower limit of gas explosion.
5. The small-aperture leakage condition simulation and risk assessment apparatus in a gas turbine fuel compartment of claim 1, wherein the multi-time assessment module is configured to perform space-time comparison logic comprising: in the case of 2.5s, judging whether the mass fraction of the fuel gas in the X direction and the Y direction at the top of the fuel tank is larger than the minimum value of the low alarm threshold value by 0.0022, in the case of 5s, judging whether the mass fraction of the fuel gas in the area below the left side of the fuel tank in the Y direction reaches 0.0022, judging whether the fuel gas in the X direction diffuses from the outlet to the inlet of the purging pipeline to the outside of the tank, after 7.5s, judging whether the mass fraction of the fuel gas in the rest area in the fuel tank is larger than 0.0022 except the areas close to the two sides of the louver, in the case of 50s, judging whether the mass fraction of the fuel gas in the most area in the fuel tank reaches the minimum value of the high alarm threshold value by 0.011, and judging whether the top area reaches or exceeds the maximum value of the high alarm threshold value by 0.022.
6. The small-aperture leakage working condition simulation and risk assessment device in a fuel tank of a gas turbine according to claim 1 is characterized in that the risk level judging module comprises a threshold value converting unit and a grading judging unit, wherein the threshold value converting unit is used for converting a lower limit of gas explosion into a corresponding mass fraction threshold value, the grading judging unit is used for generating safety, low alarm, high alarm and extremely high risk level according to a section where the mass fraction is located, and the grading judging unit is further used for comprehensively judging the overall risk level by combining the proportion of a gas diffusion range and the concentration of a key position.
7. The device for simulating and evaluating the leakage condition of the small aperture in the fuel compartment of the gas turbine according to claim 6, wherein the quality score threshold comprises a minimum value of 0.0022 corresponding to a low alarm threshold, a minimum value of 0.011 corresponding to a high alarm threshold and a maximum value of 0.022 corresponding to a high alarm threshold, and wherein the extremely high risk level judging condition comprises that the concentration of the top area exceeds 0.022 and the diffusion range covers most of the area in the compartment.
8. The device for simulating and evaluating the small-aperture leakage condition in the fuel tank of the gas turbine according to claim 1, wherein the risk level judging module is used for outputting a risk level result and a corresponding spatial distribution diagram, and the device further comprises a report generating module used for automatically generating a numerical simulation report containing the comparison result of the multi-moment evaluating module, the identification result of the diffusion characteristic identifying module and the final risk level judgment.
9. The device for simulating and evaluating the small-aperture leakage condition in the fuel tank of the gas turbine according to claim 1, further comprising a trend prediction module for predicting the distribution of the mass fraction of the fuel gas and the trend of the change of the risk level in the fuel tank at a specified future time based on the time series data acquired by the transient simulation module.

Description

Small-aperture leakage working condition simulation and risk assessment device in fuel cabin of gas turbine Technical Field The invention relates to the technical field of safety monitoring and risk assessment of gas turbines, in particular to a device for simulating and assessing the small-aperture leakage working condition in a fuel cabin of a gas turbine. Background Gas turbines are widely used in electrical, energy and industrial power systems, with their fuel supply systems typically disposed within a closed or semi-closed fuel cell. The fuel cabin is internally integrated with structures such as a fuel gas pipeline, a valve, a joint, a blowing pipeline, a shutter and the like, so that once fuel gas leakage occurs, flammable gas is easily accumulated in a limited space, and a large explosion risk exists. The existing gas turbine fuel tank safety assessment means mainly comprise leakage detection, concentration monitoring, risk level judgment based on experience and the like. The gas leakage diffusion process is partially researched and analyzed through a numerical simulation means, and the simulation precision of the small-aperture leakage working condition is insufficient for large-aperture leakage, the result display is only performed for a single moment or an integral concentration field, the system identification and the structural analysis of the gas diffusion characteristics under different spatial positions and different time nodes are lacked, the reasonable simulation time step is not controlled, the high-speed jet flow dynamics in the early stage of the small-aperture leakage is difficult to capture, and the transient simulation precision is insufficient. Meanwhile, the existing simulation analysis method is usually focused on outputting a gas concentration distribution cloud chart, lacks a mechanism for automatically comparing a simulation result with an alarm threshold value, and also lacks automatic recognition capability for key diffusion behaviors such as high-speed jet formation, top enrichment, wall surface diffusion, external channel leakage and the like, so that a risk grade evaluation result which can be directly used for engineering decision is difficult to form. In addition, in the prior art, the judgment of the gas leakage risk is mostly based on single-point concentration or a single threshold value, the diffusion range proportion of the gas in the fuel cabin, the concentration of a critical dangerous area and the evolution trend of the change with time are not comprehensively considered, and the dynamic characteristic of the development of the risk in the fuel cabin with time under the small-aperture leakage working condition is difficult to truly reflect. Therefore, the device for simulating the small-aperture leakage working condition in the fuel cabin of the gas turbine and evaluating the risk is provided for solving the existing problems. Disclosure of Invention The invention aims to solve the problems in the background art and provides a small-aperture leakage working condition simulation and risk assessment device in a fuel cabin of a gas turbine. In order to achieve the purpose, the invention provides the following technical scheme that the small-aperture leakage working condition simulation and risk assessment device in the fuel cabin of the gas turbine comprises the following steps: the model construction module is used for constructing a three-dimensional space model of the fuel cabin of the gas turbine, and arranging a small-aperture gas leakage source facing the top of the fuel cabin in the space model; The transient simulation module is used for carrying out transient numerical simulation on the diffusion process after gas leakage to obtain gas mass fraction distribution along the preset X direction and Y direction in the fuel cabin at different moments; The diffusion characteristic recognition module is used for recognizing diffusion characteristics of the gas which is diffused along the periphery of the inner wall of the fuel cabin after being leaked to form high-speed jet flow and be sprayed to the top of the fuel cabin based on the mass fraction distribution of the gas; The multi-moment evaluation module is used for comparing the gas mass fractions at different space positions in the fuel cabin with an alarm threshold value at the moments at least comprising 2.5s, 5s, 7.5s and 50 s; And the risk level judging module is used for outputting the risk level of gas leakage in the fuel cabin according to the comparison result of the multi-time evaluation module. Further, the model building module comprises a fuel tank geometric modeling unit and a leakage source parameter setting unit, wherein the leakage source parameter setting unit is used for setting the leakage aperture to be small and the leakage direction to be vertical upwards, and the three-dimensional space model built by the fuel tank geometric modeling unit comprises a blowing pipeline outlet and inlet and