| 摘要: |
| 本文建立了水冷压缩式CO2水合物直接接触蓄冷系统的仿真模型，模拟研究了不同充注压力（3.5、3.6、3.7、3.8 MPa）下蓄冷系统的降温曲线和总蓄冷量。研究发现，降温曲线的模拟结果与实验结果的相对误差依次为4.02%、4.43%、3.38%、1.89%，总蓄冷量的模拟结果与实验结果的相对误差依次为0.82%、3.41%、1.45%、1.81%，所有相对误差均小于5%，说明模型具有较好的预测能力。为了提高实验系统蓄冷性能，采用模型进行系统优化，结果表明：冷却水流量由65 mL/s增至100 mL/s时，系统预冷时间由22.5 min减至20.8 min，系统COP先增加后减少。冷却水流量为95 mL/s时，系统COP最大；冷却水温度由22 ℃升至30 ℃时，系统预冷时间由16.1 min增至21.9 min，系统COP由1.77降至1.53；当充注压力由3.5 MPa升至5.0 MPa时，排气压力由5.4 MPa升至12.1 MPa。当充注压力为5.0 MPa时，排气压力为12.1 MPa，超过压缩机警戒压力，所以低于5.0 MPa的充注压力较为安全。 |
| 关键词: CO2水合物 压缩式制冷循环 蓄冷系统 模拟 优化 |
| DOI： |
| 投稿时间：2022-02-18 修订日期：2022-05-25
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| 基金项目:国家自然科学基金（50806050）资助项目。 |
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| Simulation of Vapor Compression CO2 Hydrate Direct Contact Cold Thermal Energy Storage System |
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Duan Hankun, Xie Yingming, Yang Wenyu, Xie Meiping, Liu Daoping, Dou Binlin, Yang Liang
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| (Shanghai Key Laboratory of Multiphase Flow and Heat Transfer in Power Engineering, School of Energy and Power Engineering, University of Shanghai for Science and Technology) |
| Abstract: |
| In this study, a simulation model of a water-cooled direct contact cold thermal energy storage system using compressed CO2 hydrate was established, and the charging characteristics and total cold thermal energy storage capacity of the cold thermal energy storage system under charging pressures of 3.5 MPa, 3.6 MPa, 3.7 MPa, and 3.8 MPa were simulated. The results show that the relative errors between the simulation and experimental results of the cooling curve are 4.02%, 4.43%, 3.38%, and 1.89%, and those of the total cold thermal energy storage capacity are 0.82%, 3.41%, 1.45%, and 1.81% for the four charging pressures, respectively. All the relative errors are less than 5%; thus, the model has a good prediction ability. The model is used to optimize the system to improve its cold storage performance: when the cooling water flow rate increased from 65 mL/s to 100 mL/s, the pre-cooling time of the system decreased from 22.5 min to 20.8 min, and the COP of the system first increased and subsequently decreased. When the cooling water flow was 95 mL/s, the system COP reached maximum. When the cooling water temperature increased from 22 °C to 30 °C, the pre-cooling time of the system increased from 16.1 min to 21.9 min, and the COP of the system decreased from 1.77 to 1.53. When the charging pressure increased from 3.5 MPa to 5.0 MPa, the discharge pressure increased from 5.4 MPa to 12.1 MPa. When the charging pressure was 5.0 MPa, the discharge pressure was 12.1 MPa, which exceeded the maximum operating pressure of the compressor. Therefore, the charging pressure should be lower than 5.0 MPa for the sake of safety. |
| Key words: CO2 hydrate compression refrigeration cycle cold thermal energy storage system simulation optimization |
