Weiting Jiang^*, Tingni He^*, Chongyang Wang, Weiguo Pan, Jiang Liu

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.6, pp. 1447-1461, 2023, DOI:10.32604/fdmp.2023.025269

Abstract Computational Fluid Dynamics (CFD) is used here to reduce pressure loss and improve heat exchange efficiency in the recuperator associated with a gas turbine. First, numerical simulations of the high-temperature and low-temperature channels are performed and, the calculated results are compared with experimental data (to verify the reliability of the numerical method). Second, the flow field structure of the low-temperature side channel is critically analyzed, leading to the conclusion that the flow velocity distribution in the low-temperature side channel is uneven, and its resistance is significantly higher than that in the high-temperature side. Therefore, five alternate structural schemes are proposed… More > Graphic Abstract

Yuxing Yang, Peng Zhang^*, Meng Lv

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.6, pp. 1397-1409, 2023, DOI:10.32604/fdmp.2023.024916

Abstract The performances of turbine blades have a significant impact on the energy conversion efficiency of vertical solar power plants. In the present study, such a relationship is assessed by considering two kinds of airfoil blades, designed by using the Wilson theory. In particular, numerical simulations are conducted using the SST K − ω model and assuming a wind speed of 3–6 m/s and seven or eight blades. The two airfoils are the NACA63121 (with a larger chord length) and the AMES63212; It is shown that the torsion angle of the former is smaller, and its wind drag ratio is larger; furthermore,… More > Graphic Abstract

Xin Sun¹, Chi Zhang³, Yan Jia^1,2,*, Shikang Sui¹, Chong Zuo¹, Xueqiang Liu¹

Energy Engineering, Vol.120, No.3, pp. 729-742, 2023, DOI:10.32604/ee.2022.023398

Abstract As a part of the new energy development trend, distributed power generation may fully utilize a variety of decentralized energy sources. Buildings close to the installation location, besides, may have a considerable impact on the wind turbines’ operation. Using a combined vertical axis wind turbine with an S-shaped lift outer blade and Φ-shaped drag inner blade, this paper investigates how a novel type of upstream wall interacts with the incident wind at various speeds, the influence region of the turbulent vortex, and performance variation. The results demonstrate that the building’s turbulence affects the wind’s horizontal and vertical direction, as well… More > Graphic Abstract

Ling Yuan¹, Zhenggang Liu^2,*, Li Li³, Ming Lin¹

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.5, pp. 1129-1141, 2023, DOI:10.32604/fdmp.2023.023538

Abstract The blades of large-scale wind turbines can obviously deform during operation, and such a deformation can affect the wind turbine’s output power to a certain extent. In order to shed some light on this phenomenon, for which limited information is available in the literature, a bidirectional fluid-structure interaction (FSI) numerical model is employed in this work. In particular, a 5 MW large-scale wind turbine designed by the National Renewable Energy Laboratory (NREL) of the United States is considered as a testbed. The research results show that blades’ deformation can increase the wind turbine’s output power by 135 kW at rated working conditions.… More > Graphic Abstract

Anfeng Zhu¹, Qiancheng Zhao^1,*, Lin Gui¹, Tianlong Yang¹, Xuebing Yang²

Energy Engineering, Vol.120, No.2, pp. 425-444, 2023, DOI:10.32604/ee.2023.023049

Abstract To ensure wind turbine (WT) safe operations and improve the utilization rate of wind energy, effective evaluation of the operation state of the pitch system is critical. Therefore, a new method was proposed to evaluate the operation state of the pitch system of WT based on fuzzy comprehensive evaluation. Firstly, based on SCADA data, the working state of the pitch system under rated power state and power state of WT were analyzed. Secondly, through the analysis of characteristic parameters and physical mechanism of the pitch system, the consistency principle of characteristic parameters, the stability principle of power under rated state,… More >

Yajing Zhang¹, Chaoyang Song², Zhiguo Li^2,*

Energy Engineering, Vol.120, No.2, pp. 501-510, 2023, DOI:10.32604/ee.2022.021423

Abstract To overcome the problems of natural decreases in power quality, and to eliminate wind speed fluctuation due to wind shear and tower shadow effect arising from wind turbine structural parameters, an improved prediction model accounting for the dual effect of wind shear and tower shadow is, in this paper, built. Compared to the conventional prediction model, the proposed model contains a new constraint condition, which makes the disturbance term caused by the tower shadow effect always negative so that the prediction result is closer to the actual situation. Furthermore, wind turbine structural parameters such as hub height, rotor diameter, the… More > Graphic Abstract

Rong Yuan¹, Ruitao Chen², Haiqing Li^3,*, Wenke Yang¹, Xiaoxiao Li¹

CMES-Computer Modeling in Engineering & Sciences, Vol.135, No.3, pp. 2331-2347, 2023, DOI:10.32604/cmes.2023.023788

Abstract Wind power is a kind of important green energy. Thus, wind turbines have been widely utilized around the world. Wind turbines are composed of many important components. Among these components, the failure rate of the transmission system is relatively high in wind turbines. It is because the components are subjected to aerodynamic loads for a long time. In addition, its inertial load will result in fatigue fracture, wear and other problems. In this situation, wind turbines have to be repaired at a higher cost. Moreover, the traditional reliability methods are difficult to deal with the above challenges when performing the… More >

Jianghua Cheng^1,2, Xiaojian Li², Lei Shi^3,*, Kangbo Lu³, Ling Leng³

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.4, pp. 959-975, 2023, DOI:10.32604/fdmp.2023.023687

Abstract Power deterioration is a major problem for diesel engines operating at high altitudes. This problem stems from the limited availability of turbocharger energy, which is not enough to increase the boost pressure to the required level. In this study, a control strategy is introduced in order to achieve engine power recovery at different altitudes. It is shown that as the altitude increases from 0 to 4500 m, the required boost pressure ratio increases from 2.4 to 4.3. The needed turbocharger energy should be increased accordingly by 240%, and the TCC (turbine characterization coefficient) should be adjusted within wide ranges. A… More >

Mehrdad Ahmadi Kamarposhti^1,*, Ilhami Colak², Phatiphat Thounthong³, Kei Eguchi⁴

CMC-Computers, Materials & Continua, Vol.74, No.2, pp. 4547-4570, 2023, DOI:10.32604/cmc.2023.034082

Abstract The present study suggests that series voltage injection is more effective than parallel current injection to improve voltage quality on the load side. The line voltage can be accurately symmetrized at the connection point by creating and controlling a series voltage component in each phase. This is more reliable and effective than parallel current injection. A dynamic voltage restorer (DVR) and a distribution static synchronous compensator (DSTATCOM) were utilized to provide the required power. The DVR is an effective and modern device utilized in parallel within the grid and can protect sensitive loads from voltage problems in the grid by… More >

Billel Meghni¹, Afaf Benamor², Oussama Hachana³, Ahmad Taher Azar^4,5,*, Amira Boulmaiz⁶, Salah Saad¹, El-Sayed M. El-kenawy^7,8, Nashwa Ahmad Kamal⁹, Suliman Mohamed Fati⁵, Naglaa K. Bahgaat¹⁰

CMC-Computers, Materials & Continua, Vol.74, No.2, pp. 3977-3996, 2023, DOI:10.32604/cmc.2023.029838

Abstract The integration of wind turbines (WTs) in variable speed drive systems belongs to the main factors causing low stability in electrical networks. Therefore, in order to avoid this issue, WTs hybridization with a storage system is a mandatory. This paper investigates WT system operating at variable speed. The system contains of a permanent magnet synchronous generator (PMSG) supported by a battery storage system (BSS). To enhance the quality of active and reactive power injected into the network, direct power control (DPC) scheme utilizing space-vector modulation (SVM) technique based on proportional-integral (PI) control is proposed. Meanwhile, to improve the rendition of… More >