Numerical simulation of extrusion swell effect of solid propellant slurryWu, Yue; Wang, Meng
doi: 10.1117/12.3044442pmid: N/A
Aiming at the viscoelastic flow of solid propellant slurry, the extrusion swelling effect under the FENE-P constitutive model was studied based on the CFD Polyflow simulation software, which provided a new idea for solving the free-surface flow problem of viscoelastic fluid. The results show that the closer the slurry fluid is to the wall, the smaller the velocity; In the process of simulated extrusion, the pressure gradually decreases along the flow direction of the slurry, and suddenly disappears to zero at the outlet of the die due to the constraint of the model wall on the slurry; Extrusion swelling ratio increases with the increase of relaxation time.
Application of solid waste treatment and resource utilization in tertiary oil recovery in environmental engineeringLiu, Bao
doi: 10.1117/12.3044798pmid: N/A
In this paper, thermogravimetric IR analysis was performed for the pyrolysis and oil-bearing sludge of two solid wastes generated from tertiary oil recovery. The characteristics of combustion, parameters of combustion, synergistic effect of combustion, combustion characteristics of each component, dynamic parameters of combustion and deposition characteristics of gas phase products were studied. It is found that the combustion of residual oil and grease sludge after distillation can be divided into three different combustion stages. The burning property of the residual oil is improved after adding the sludge. In the pyrolysis process, the mixed combustion of residual oil and sludge has an obvious synergistic effect. Under different fuel conditions, there are both promoting and restricting effects between residual oil and oily sludge.
Simulation study of phosphorus remediation using lanthanum chloride-modified fly ash and Mg-O modified biochar at the sediment water interfaceJi, Minghao; Men, Zhigao; Zhang, Jihua; Tian, Ao; Wang, Jiayi; Sun, Xiaoyu; Yang, Chengnian; Cheng, Shuailong; Wang, Yijie; Chen, Wenlong; Gao, Zilan; Chai, Beibei
doi: 10.1117/12.3044560pmid: N/A
Water eutrophication is a significant environmental governance challenge faced by the world today, with nutrient overloading being a primary cause, while aquatic sediment serves as the main storage site for these nutrients and other pollutants. This study focused on the Guangfu Ancient City Moat in Handan City as the research subject, where lanthanum-modified fly ash microspheres and Mg-O modified biochar, independently developed and processed, were employed in an in-situ remediation efficiency simulation within containment boxes. The study also investigated phosphorus recovery and utilization. The removal rates of total phosphorus in the containment boxes with fly ash microspheres, biochar, fly ash microspheres wrapped in non-woven fabric, and biochar wrapped in non-woven fabric were 51.91%, 66.67%, 84.52%, and 84.14% respectively, with removal effectiveness ranking as NO. 4’ NO. 4” > NO. 3 NO. 2. The research indicated that both biochar and fly ash microspheres displayed outstanding performance in phosphorus adsorption, with fly ash microspheres being more cost-effective compared to activated carbon. The containment box experiments effectively demonstrated the significant impact of fly ash microspheres in the efficient recovery of phosphorus resources and the improvement of aquatic environments, offering essential insights for the integrated management of water quality and soil.
Applicability and optimization method of grey GM(1,1) model in atmospheric environment ecological safety evaluationZhou, Chaofan; Wang, Yiyong; Huang, Rong; Xue, Zhaona; Tian, Siting
doi: 10.1117/12.3044500pmid: N/A
In order to explore the applicability of the gray GM(1,1) prediction model for predicting the results of the ecological safety assessment of the atmospheric environment under different changing trends. In this paper, Xi’an City and Baoji City in Shaanxi Province, China, as representative cities with smooth and drastic changes in the atmospheric environment, respectively, a unified evaluation index system was constructed, and the composite index method and TOPSIS method were used for the evaluation of atmospheric ecological safety. By constructing a gray GM(1,1) prediction model and comparing the applicability of the GM(1,1) prediction of the two methods, it was concluded that the atmospheric evaluation results calculated by the two methods were suitable for constructing the prediction, but it was found that when Xi’an City was used as a sample, the evaluation results changed less and the gray GM(1,1) prediction was more accurate for longer years. When Baoji City was used as a sample, the evaluation results varied greatly, and the gray GM(1,1) predicted that there were shorter prediction years in the evaluation results derived from both methods, exceeding the evaluation standard and detached from the objective reality. Baoji City as a sample in the comprehensive index method of evaluation through the prediction of the original value of the indicator factor to optimize, TOPSIS method by predicting the positive and negative ideal solution for optimization, optimization, can be in accordance with the established development trend of the sample city in the context of the prediction of a longer unit of atmospheric ecological safety evaluation results, and in line with the objective reality and evaluation standards.
Research status of creep damage evaluation methods for nickel-based high-temperature alloysZheng, Jianjun; Guo, Yang; Tan, Xiaomeng
doi: 10.1117/12.3044785pmid: N/A
Assessing the remaining life of key components in high temperature service is an essential element of strategic plant maintenance and plant life extension programs. Especially for nickel based high-temperature alloys, which are generally operated under service conditions above 600C. In this paper, a number of techniques and methods for the creep damage evaluation methods have been introduced over past several decades. The application and limitation of several main approaches are discussed in detail. At last, some suggestions for the further research work are proposed.
Urban energy planning and renewable energy integration driven by energy dataLi, Jinhu; Lin, Haiyu; Liu, Yanqiu; Xie, Chi; Bao, Zhiyan
doi: 10.1117/12.3044839pmid: N/A
Urban energy planning plays an important role in the national sustainable development strategy. In recent years, urban energy planning has gradually received attention from the government and academia and has shifted from qualitative research to quantitative research. As urban energy planning data continues to accumulate, data analysis can be used to help planners better understand the operation of the energy system and provide decision support for optimizing the urban energy system. By analyzing the energy planning of a certain region, this article explores the impact of urban energy planning data on the integration and comprehensive utilization of urban renewable energy, with a view to providing a reference for future urban energy planning. After experiments, it was found that the application efficiency of solar power generation in cities could reach up to 95.6%, and the utilization rate could reach up to 98.6%. It is a typical successful case of integrating urban energy planning and renewable energy.
Reactivity control in typical unit operation activities of third-generation nuclear power plantsWu, Aimin; Zhang, Weibin; Zhang, Yu
doi: 10.1117/12.3044458pmid: N/A
Effective reactivity management, as an important means to ensure the safe operation of nuclear power plants, is a policy requirement proposed by the World Association of Nuclear Power Operators (WANO) for various nuclear power plants and has gradually become a factor that designers need to consider in the design of reactivity control systems. In recent years, there has been an urgent need for domestic operational facilities to enhance their reactivity management capabilities, and at the same time, advanced operational design for third-generation nuclear power also urgently needs to understand relevant information. However, due to various reasons, there are few research discussions on reactivity control and management in the operation of nuclear power plants both domestically and internationally. The AP1000 power plant adopts the latest designs such as Mechanical Shimming (MSHIM) and Rapid Power Reduction System (RPR). The operating range of its units is wide and diverse, and the corresponding reactive management measures are highly representative. Based on the above issues, the core monitoring software was used to simulate and summarize three typical operational activities of the AP1000 power plant, including start-up, unit peak shaving, and rapid power reduction system triggering. The reactivity change characteristics and control elements were analyzed in detail, and corresponding key monitoring parameters were proposed. A detailed reactivity management strategy was provided. This has significant reference significance for improving the reactivity management capability of domestic nuclear power plants and strengthening operational safety, especially for the operational design of reactivity control for third-generation nuclear power units in China.
Improvement CO2 absorption of calcium-based by zirconia/aluminaGuo, Neng; Zhu, Dongdong; Kou, Xueyong; Li, Shuaipeng; Chen, Shengwen; Sun, Zhiguo
doi: 10.1117/12.3044455pmid: N/A
In the field of solid absorbents for CO2, the use of calcium-based waste for CO2 capture not only enables the resourceful use of waste but also reduces the cost of carbon dioxide capture. In this study, CaO was utilized as the calcium-based absorbent, while ZrO2 and Al2O3 were employed as modifiers. The properties of ZrO2/Al2O3/CaO composite absorber for cyclic CO2 absorption was investigated. The findings indicated that the concurrent addition of ZrO2 and Al2O3 could enhance the cyclic absorption stability and carbonation efficiency of CaO. The carbonation uptake efficiency of the absorber was enhanced by about 6% after the fifth absorption cycle compared with that without the addition of ZrO2 and Al2O3. The incorporation of ZrO2 and Al2O3 induced structural modifications in the calcium-based absorbent, providing support and separation between the CaO particles, thereby preventing void fusion. This enables the absorbent to maintain high activity and stability, while also delaying the sintering process of CaO.