Rongxin Zhang^1,*, Chengying Yang^2,3, Xuetao Li¹

Energy Engineering, Vol.119, No.6, pp. 2489-2511, 2022, DOI:10.32604/ee.2022.021517 - 14 September 2022

Abstract Buildings are the main energy consumers across the world, especially in urban communities. Building smartization, or the smartification of housing, therefore, is a major step towards energy grid smartization too. By controlling the energy consumption of lighting, heating, and cooling systems, energy consumption can be optimized. All or some part of the energy consumed in future smart buildings must be supplied by renewable energy sources (RES), which mitigates environmental impacts and reduces peak demand for electrical energy. In this paper, a new optimization algorithm is applied to solve the optimal energy consumption problem by considering… More >

Yanliang Qiu^1,2, Bin Xiong^1,2, Zhe Hou^1,2,*, Lin Luo³

Energy Engineering, Vol.119, No.6, pp. 2243-2254, 2022, DOI:10.32604/ee.2022.021322 - 14 September 2022

Abstract The shrink fit retaining ring is currently the easiest to install and the most widely used end fixed for structure AC excitation variable speed generator-motor rotor end windings. However, the current research on the effect of high strength sealing on the ventilation and heat dissipation performance of the end is not enough. In this paper, based on the actual structural parameters and periodic symmetry simplification, the three-dimensional coupled calculation model of fluid field and temperature field is established. After solving the fluid and thermal equations, the influence of the length of rotor support block, the More >

Ting Chen¹, Oh Kyung Kwon^2,*

Energy Engineering, Vol.119, No.6, pp. 2231-2242, 2022, DOI:10.32604/ee.2022.021289 - 14 September 2022

Abstract With the limited production and use of R245fa, environmentally friendly refrigerant has attracted the attention of researchers. Due to the similar thermal characteristics, R1233zd(E) is considered to be an ideal substitute for R245fa in heat pump systems. In this study, the performance and economic analysis of heat pump systems with R245fa and R1233zd(E) as refrigerants are carried out. The results show that the total cost of R1233zd(E) system is more than 10% higher than that of R245fa system under the same heating load. With the increase of condensation temperature, the heating capacity of both systems More >

Bing Wang^1,2,*, Zhongxun Li¹, Rui Shi¹, Yuzheng Zhang¹, Yao Yao¹

Energy Engineering, Vol.119, No.6, pp. 2469-2487, 2022, DOI:10.32604/ee.2022.021171 - 14 September 2022

Abstract With policy incentives for the coalbed methane in energy industry, coalbed methane from coal production has been effectively improved by technology innovations in coalbed methane extraction and utilization. The progress of coalbed methane promotes the clean construction of energy system and contributes to carbon neutrality target. To quantitatively measure the contributions of the coalbed methane in energy industry, this paper builds a carbon emissions accounting system for coalbed methane in China and assesses the historical co-benefits of coalbed methane utilization from the aspects of emissions reduction, safety and economy. By using the parameters of gas… More >

Yangsheng Sun¹, Zhihua Wang¹, Gaoqin Wang², Beibei Wang^3,*

Energy Engineering, Vol.119, No.6, pp. 2193-2210, 2022, DOI:10.32604/ee.2022.020943 - 14 September 2022

Abstract The market power mitigation method of the supply-side has become one of the key points affecting the stability of the electricity spot market. Different mitigation mechanisms are used in the current mature electricity markets of the world. However, the same market power mitigation mechanism shows different effects in different market environments. Every market operator in the world needs the most efficient way to mitigate market power. Considering that there is no relevant literature discussing the market power effects of different mitigation methods in detail, the mitigation effects need to be discussed and further researched. So, More >

Rao Fu^1,*, Liming Wang², Xuesong Huo², Pei Pei², Haitao Jiang³, Zhongxing Fu⁴

Energy Engineering, Vol.119, No.6, pp. 2621-2636, 2022, DOI:10.32604/ee.2022.020873 - 14 September 2022

Abstract The power infrastructure of the power system is massive in size and dispersed throughout the system. Therefore, how to protect the information security in the operation and maintenance of power equipment is a difficult problem. This paper proposes an improved time-stamped blockchain technology biometric fuzzy feature for electrical equipment maintenance. Compared with previous blockchain transactions, the time-stamped fuzzy biometric signature proposed in this paper overcomes the difficulty that the key is easy to be stolen by hackers and can protect the security of information during operation and maintenance. Finally, the effectiveness of the proposed method More >

Yuxia Han^1,2, Jianwen Wang^1,2,*, Xin Li³, Xueqing Dong^1,2, Caifeng Wen^1,2

Energy Engineering, Vol.119, No.6, pp. 2297-2317, 2022, DOI:10.32604/ee.2022.020858 - 14 September 2022

Abstract The evolution laws of the large-eddy coherent structure of the wind turbine wake have been evaluated via wind tunnel experiments under uniform and turbulent inflow conditions. The spatial correlation coefficients, the turbulence integral scales and power spectrum are obtained at different tip speed ratios (TSRs) based on the time-resolved particle image velocity (TR-PIV) technique. The results indicate that the large-eddy coherent structures are more likely to dissipate with an increase in turbulence intensity and TSR. Furthermore, the spatial correlation of the longitudinal pulsation velocity is greater than its axial counterpart, resulting into a wake turbulence… More >

Xiyang Li¹, Yuhao Jia², Hui Zhang^1,*, Bin Cheng¹

Energy Engineering, Vol.119, No.6, pp. 2549-2567, 2022, DOI:10.32604/ee.2022.020854 - 14 September 2022

Abstract Icing can significantly change the geometric parameters of wind turbine blades, which in turn, can reduce the aerodynamic characteristics of the airfoil. In-depth research is conducted in this study to identify the reasons for the decline of wind power equipment performance through the icing process. An accurate experimental test method is proposed in a natural environment that examines the growth and distribution of ice formation over the airfoil profile. The mathematical models of the airfoil chord length, camber, and thickness are established in order to investigate the variation of geometric airfoil parameters under different icing… More >

Ruoqiong Li^1,*, Linrun Xiao¹, Jingtao Lu², Xin Li²

Energy Engineering, Vol.119, No.6, pp. 2533-2548, 2022, DOI:10.32604/ee.2022.020803 - 14 September 2022

Abstract In electrified railways, traction load not only fluctuates between peaks and valleys, but also has a situation of low utilization rate of average load throughout the day and short overload. The traction transformer selects the capacity with the peak load as the demand boundary, which will cause the capacity utilization rate to be low and even lead to the economic decline of the traction power supply system. This article summarizes the existing configuration methods for capacity optimization of traction transformer. Then under the conditions of energy storage and new energy access to traction power supply… More >

Jiageng Zhang¹, Zhengfeng Wang², Jiguang Huang¹, Chao Cheng¹, Heng Zhang¹, Dan Gao^1,*

Energy Engineering, Vol.119, No.6, pp. 2277-2296, 2022, DOI:10.32604/ee.2022.020795 - 14 September 2022

Abstract

Nowadays, the zero liquid discharge of flue gas desulfurization (FGD) wastewater from coal-fired units has attracted the attention of all countries in the world. The pretreatment methods generally have the problems of high operation cost, small treatment capacity, and poor flexibility. However, the membrane method can avoid the above problems. In the current research, it has not been found that someone directly uses submerged ultrafiltration to pretreat FGD wastewater. Therefore, this paper innovatively proposed to directly use ceramic ultrafiltration membrane to treat FGD wastewater, which can ensure effluent quality and improve the flexibility of the pretreatment

… More >