CN-122016916-A - Method for evaluating overall performance attenuation of thermal energy storage system

CN122016916ACN 122016916 ACN122016916 ACN 122016916ACN-122016916-A

Abstract

The invention provides a method for evaluating the overall performance attenuation of a thermal energy storage system, which belongs to the technical field of thermal energy storage systems, and the method comprises the steps of arranging a distributed optical fiber temperature sensor in a heat storage medium, establishing a multidimensional temperature measurement system by combining infrared thermal imaging equipment, continuously acquiring temperature data by utilizing a dynamic sliding time window to form a space-time temperature data matrix, the thermal field reconstruction optimization model of the multi-layer encoding and decoding architecture is combined with an attention mechanism and an information bottleneck principle to realize high-precision reconstruction of an internal complete three-dimensional temperature field, dynamic performance parameters such as instantaneous heat storage efficiency, temperature uniformity coefficient, heat loss rate and the like are calculated based on a reconstruction result, and finally, comprehensive performance attenuation evaluation indexes are formed to realize accurate judgment of the system state, so that the technical problem that the performance attenuation evaluation precision is insufficient due to the fact that the internal complete three-dimensional temperature field of the thermal energy storage system is difficult to reconstruct accurately is solved.

Inventors

WANG ZEZHONG
ZHANG LEI
ZHANG CHENXI
ZHU CHANG
WEI FEI
BAI DINGRONG

Assignees

鄂尔多斯实验室
清华大学

Dates

Publication Date: 20260512
Application Date: 20251208

Claims (10)

1. A thermal energy storage system integral performance attenuation assessment method is characterized in that distributed optical fiber temperature sensors are respectively arranged in a heat storage medium of a thermal energy storage system along the radial direction and the axial direction, infrared thermal imaging equipment is installed on the outer surface of a heat storage container and used for surface temperature field measurement, a dynamic sliding time window is established, temperature data of the distributed optical fiber temperature sensors and the infrared thermal imaging equipment are continuously collected through the dynamic sliding time window to form a space-time temperature data matrix, the space-time temperature data matrix is processed through a thermal field reconstruction optimization model, integral three-dimensional temperature field distribution in the heat storage system is reconstructed through a numerical inversion algorithm to obtain a temperature field reconstruction result, dynamic performance parameters of the heat storage system including instantaneous heat storage efficiency, temperature uniformity coefficients and heat loss rate are calculated based on the temperature field reconstruction result, a performance attenuation curve is constructed by the dynamic performance parameters and the heat storage system operation time, performance attenuation model parameters are updated in real time through an online parameter identification method, a clustering analysis recognition mode is adopted to recognize the data aggregation distribution mode of the dynamic performance parameters, when the clustering analysis recognizes the dynamic performance parameter data aggregation distribution mode, automatic classification and organization of the dynamic performance parameters are achieved through clustering center estimation and boundary determination, a multi-performance parameter reconstruction algorithm is established, and an integral performance coefficient thermal energy storage coefficient integral performance attenuation rate is assessed, and integral performance coefficient thermal energy storage coefficient integral performance coefficient attenuation coefficient is assessed.
2. The method for evaluating the overall performance attenuation of a thermal energy storage system according to claim 1, wherein the distributed optical fiber temperature sensor is arranged at a pitch of 0.1 to 0.3 times the characteristic size of the heat storage container, the distributed optical fiber temperature sensor is a temperature measuring device based on the raman scattering principle, and the temperature distribution along the optical fiber path is measured by the back scattering intensity variation of the optical signal in the optical fiber.
3. The method of claim 2, wherein the thermal storage container characteristic dimension is a major geometry of the thermal storage container, including a maximum of diameter, height or length, and the dynamic sliding time window has a time length of 1.5 to 3 times a thermal response time constant of the thermal storage system.
4. A thermal energy storage system overall performance decay assessment method according to claim 3 and wherein said dynamic sliding time window is a time series data processing technique, continuous monitoring and analysis of system dynamics is achieved by continuous movement of a fixed length time window on a time axis, and the thermal response time constant of the thermal storage system is the characteristic time required for the thermal storage system to reach steady state from receiving thermal input.
5. The method of claim 4, wherein the space-time temperature data matrix is a three-dimensional data structure formed by arranging temperature measurement data according to spatial position and time sequence, the thermal field reconstruction optimization model is a temperature field reconstruction algorithm based on sparse representation theory and variation optimization, and the complete temperature field is reconstructed from the limited point data by minimizing a weighted sum of reconstruction errors and regularization terms.
6. The method for evaluating the overall performance attenuation of a thermal energy storage system according to claim 5, wherein the numerical inversion algorithm is a calculation method for observing the internal state of the data inversion system, the internal temperature distribution is obtained by solving a heat transfer inverse problem in the temperature field reconstruction, and the temperature field reconstruction result is the internal complete three-dimensional temperature field distribution data of the thermal energy storage system obtained by the numerical inversion algorithm.
7. The method of claim 6, wherein the instantaneous heat storage efficiency is a ratio of heat storage capacity to input heat, the temperature uniformity coefficient is a ratio of standard deviation of a temperature field to average temperature, and the heat loss rate is a ratio of heat loss to total heat storage capacity.
8. The method for evaluating the overall performance decay of a thermal energy storage system according to claim 7, wherein the performance decay curve is a functional relation describing a law of variation of dynamic performance parameters with time, the on-line parameter identification method is an adaptive algorithm for estimating model parameters of the system in real time, and the model parameters are dynamically updated by a recursive least square method or a Kalman filtering technology.
9. The method of claim 8, wherein the efficiency is improved by a centralized processing mode when the degree of dispersion of the instantaneous heat storage efficiency data is less than a threshold value of the concentration requirement of 0.05, and the complexity is dealt with by a distributed processing strategy when the degree of dispersion of the temperature uniformity coefficient data is greater than 0.15.
10. The method for evaluating the overall performance degradation of a thermal energy storage system according to claim 9, wherein the centralized processing mode refers to a unified processing strategy adopted when the degree of data dispersion is small, processing precision and efficiency are improved through centralized computing resources, and the distributed processing strategy refers to a distributed processing method adopted when the data complexity is high, and computing tasks are distributed to a plurality of processing units to be executed in parallel.

Description

Method for evaluating overall performance attenuation of thermal energy storage system Technical Field The invention belongs to the technical field of heat energy storage systems, and particularly relates to a method for evaluating overall performance attenuation of a heat energy storage system. Background The thermal energy storage system is used as a key technology in the field of new energy, the performance evaluation of the thermal energy storage system mainly depends on a traditional temperature measurement method, temperature data are acquired by arranging a temperature sensor on the surface or a limited position of a heat storage container, and the heat storage efficiency and the heat loss characteristic of the system are calculated and analyzed by combining numerical simulation. The traditional method is widely applied to scenes such as solar thermal power stations, industrial waste heat recovery systems, district heating systems and the like, and the running state of the system is estimated by monitoring the temperature change of key positions. However, the traditional temperature measurement method is limited by the number of measuring points and the spatial distribution, only the temperature information of a local area of the heat storage system can be obtained, and the internal complex heat transfer process and the temperature field distribution characteristics are difficult to comprehensively reflect, so that a large deviation exists in performance evaluation based on limited measuring point data. In the prior art, due to the lack of an effective internal complete temperature field reconstruction method, the real three-dimensional temperature distribution in the heat storage system cannot be accurately obtained, so that the accuracy and reliability of performance attenuation evaluation are insufficient. That is, in the prior art, there is a technical problem that the accuracy of performance attenuation assessment is insufficient due to the fact that a complete three-dimensional temperature field inside a thermal energy storage system is difficult to reconstruct accurately. Disclosure of Invention In view of the above, the invention provides a method for evaluating the overall performance attenuation of a thermal energy storage system, which can solve the technical problem that the accuracy of evaluating the performance attenuation is insufficient due to the fact that the complete three-dimensional temperature field inside the thermal energy storage system is difficult to reconstruct accurately in the prior art. The invention provides a method for evaluating the overall performance attenuation of a thermal energy storage system, which is realized by respectively arranging distributed optical fiber temperature sensors in a heat storage medium of the thermal energy storage system along the radial direction and the axial direction, simultaneously installing infrared thermal imaging equipment on the outer surface of a heat storage container for surface temperature field measurement, establishing a dynamic sliding time window, continuously collecting temperature data of the distributed optical fiber temperature sensors and the infrared thermal imaging equipment through the dynamic sliding time window to form a space-time temperature data matrix, processing the space-time temperature data matrix by utilizing a thermal field reconstruction optimization model, reconstructing the integral three-dimensional temperature field distribution in the heat storage system by utilizing a numerical inversion algorithm to obtain a temperature field reconstruction result, calculating dynamic performance parameters of the heat storage system, including instantaneous heat storage efficiency, a temperature uniformity coefficient and a heat loss rate, constructing a performance attenuation curve by utilizing the temperature field reconstruction result and the heat storage system operation time, updating the performance attenuation model parameters in real time by utilizing an online parameter identification method, adopting a clustering analysis to identify a data aggregation distribution mode of the dynamic performance parameters, realizing automatic classification of the dynamic performance parameters by utilizing a clustering center estimation and a determination algorithm when the clustering analysis identifies the dynamic performance parameter data aggregation distribution mode, and establishing a multi-mode thermal storage efficiency, and evaluating the overall performance coefficient attenuation coefficient of the thermal energy storage system. The arrangement space of the distributed optical fiber temperature sensors is 0.1 to 0.3 times of the characteristic size of the heat storage container, the distributed optical fiber temperature sensors are temperature measuring devices based on the Raman scattering principle, and the temperature distribution along the optical fiber path is measured through the back scatter