Wenlu Ji^*, Teng Tu, Nan Ma

Energy Engineering, Vol.121, No.5, pp. 1223-1243, 2024, DOI:10.32604/ee.2024.046112

Abstract To improve the resilience of a distribution system against extreme weather, a fuel-based distributed generator (DG) allocation model is proposed in this study. In this model, the DGs are placed at the planning stage. When an extreme event occurs, the controllable generators form temporary microgrids (MGs) to restore the load maximally. Simultaneously, a demand response program (DRP) mitigates the imbalance between the power supply and demand during extreme events. To cope with the fault uncertainty, a robust optimization (RO) method is applied to reduce the long-term investment and short-term operation costs. The optimization is formulated as a tri-level defender-attacker-defender (DAD)… More >

Junhui Li¹, Xuanzhong Luo^1,2, Changxing Ge³, Cuiping Li^1,*, Changrong Wang⁴

Energy Engineering, Vol.121, No.4, pp. 869-893, 2024, DOI:10.32604/ee.2024.029722

Abstract Peak load and wind energy emission pressure rise more as wind energy penetration keeps growing, which affects the stabilization of the PS (power system). This paper suggests integrated optimal dispatching of thermal power generators and BESS (battery energy storage system) taking wind energy emission grading punishment and deep peak clipping into consideration. Firstly, in order to minimize wind abandonment, a hierarchical wind abandonment penalty strategy based on fuzzy control is designed and introduced, and the optimal grid-connected power of wind energy is determined as a result of minimizing the peak cutting cost of the system. Secondly, considering BESS and thermal… More > Graphic Abstract

Pankaj Saha^a, Gautam Biswas^a,b,*

Frontiers in Heat and Mass Transfer, Vol.2, No.3, pp. 1-5, 2011, DOI:10.5098/hmt.v2.3.3008

Abstract Detailed flow structure in turbulent flows through a rectangular channel containing built-in winglet type vortex generators have been analyzed by means of solutions of the full Navier-Stokes equations using a Large-Eddy Simulation (LES) technique. The Reynolds number of investigation is 6000. The geometry of interest consists of a rectangular channel with a built-in winglet pair on the bottom wall with common-flow-down arrangement. The winglet pair induces streamwise longitudinal vortices behind it. The vortices swirl the flow around the axis parallel to the mainstream direction and disrupt the growth of thermal boundary layer entailing enhancement of heat transfer. The influence of… More >

Deni Ainur Rokhim^1,2, Isma Yanti Vitarisma¹, Sumari Sumari^1,*, Yudhi Utomo¹, Muhammad Roy Asrori¹

Journal of Renewable Materials, Vol.12, No.2, pp. 275-284, 2024, DOI:10.32604/jrm.2023.043419

Abstract The high consumption of electricity and issues related to fossil energy have triggered an increase in energy prices and the scarcity of fossil resources. Consequently, many researchers are seeking alternative energy sources. One potential technology, the Microbial Fuel Cell (MFC) based on rice, vegetable, and fruit wastes, can convert chemical energy into electrical energy. This study aims to determine the potency of rice, vegetable, and fruit waste assisted by Cu/Mg electrodes as a generator of electricity. The method used was a laboratory experiment, including the following steps: electrode preparation, waste sample preparation, incubation of the waste samples, construction of a… More >

Feng Zhao, Jinshuo Zhang^*, Xiaoqiang Chen, Ying Wang

Energy Engineering, Vol.121, No.2, pp. 339-358, 2024, DOI:10.32604/ee.2023.043082

Abstract In the DC microgrid, the lack of inertia and damping in power electronic converters results in poor stability of DC bus voltage and low inertia of the DC microgrid during fluctuations in load and photovoltaic power. To address this issue, the application of a virtual synchronous generator (VSG) in grid-connected inverters control is referenced and proposes a control strategy called the analogous virtual synchronous generator (AVSG) control strategy for the interface DC/DC converter of the battery in the microgrid. Besides, a flexible parameter adaptive control method is introduced to further enhance the inertial behavior of the AVSG control. Firstly, a… More >

Qiangfei Cao¹, Huilai Wang², Zijia Hui¹, Lingyun Chen^2,*

Energy Engineering, Vol.121, No.2, pp. 499-521, 2024, DOI:10.32604/ee.2023.042702

Abstract Distribution generation (DG) technology based on a variety of renewable energy technologies has developed rapidly. A large number of multi-type DG are connected to the distribution network (DN), resulting in a decline in the stability of DN operation. It is urgent to find a method that can effectively connect multi-energy DG to DN. photovoltaic (PV), wind power generation (WPG), fuel cell (FC), and micro gas turbine (MGT) are considered in this paper. A multi-objective optimization model was established based on the life cycle cost (LCC) of DG, voltage quality, voltage fluctuation, system network loss, power deviation of the tie-line, DG… More >

Baogang Chen¹, Fenglin Miao^2,*, Jing Yang¹, Chen Qi², Wenyan Ji¹

Energy Engineering, Vol.121, No.2, pp. 541-555, 2024, DOI:10.32604/ee.2023.028327

Abstract Energy storage systems (ESS) and permanent magnet synchronous generators (PMSG) are speculated to be able to exhibit frequency regulation capabilities by adding differential and proportional control loops with different control objectives. The available PMSG kinetic energy and charging/discharging capacities of the ESS were restricted. To improve the inertia response and frequency control capability, we propose a short-term frequency support strategy for the ESS and PMSG. To this end, the weights were embedded in the control loops to adjust the participation of the differential and proportional controls based on the system frequency excursion. The effectiveness of the proposed control strategy was… More >

Amnart Boonloi^a, Withada Jedasadaratanachai^b,*

Frontiers in Heat and Mass Transfer, Vol.5, pp. 1-15, 2014, DOI:10.5098/hmt.5.19

Abstract 3D numerical investigations for heat transfer characteristics and flow configurations in a fin–and-oval-tube heat exchanger with V-tip pointing downstream delta winglet pairs (DDWP) are examined. The DDWPs are placed on the fin surface with pointing downstream and the oval tube row number is set at three in a staggered arrangement. The flow attack angles (θ = 15°, 30°, 45° and 60°) and the distance from V-tip to the oval tube center in transverse axis (a = 3.77, 4.77 and 5.77 mm) are investigated for Reynolds number based on hydraulic diameter, Re = 500 – 2500. The numerical results are compared… More >

Amnart Boonloi^*

Frontiers in Heat and Mass Transfer, Vol.5, pp. 1-12, 2014, DOI:10.5098/hmt.5.8

Abstract A mathematical analysis of the heat transfer enhancement, thermal performance and flow configurations in a heat exchanger square duct with diagonal inserted plate vortex generators is presented. The 30o V–shaped baffles are modified and placed on the double sides of the thin plate or frame (with no plate) which inserted diagonally in the square duct. The effects of blockage ratio (b/H, BR), the pitch ratio (p/H, PR), flow direction (V–Downstream and V–Upstream) and configuration of inserting plate are investigated for Reynolds number based on the hydraulic diameter of the square duct, D_h, Re = 100 – 2000. The finite volume… More >

Tian Li^1,2,*, Hao Liang¹, Zerui Xiang², Jiye Zhang¹

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.2, pp. 463-473, 2024, DOI:10.32604/fdmp.2023.043618

Abstract A relatively high aerodynamic drag is an important factor that hinders the further acceleration of high-speed trains. Using the shear stress transport (SST) k-ω turbulence model, the effect of various vortex generator types on the aerodynamic characteristics of an ICE2 (Inter-city Electricity) train has been investigated. The results indicate that the vortex generators with wider triangle, trapezoid, and micro-ramp arranged on the surface of the tail car can significantly change the distribution of surface pressure and affect the vorticity intensity in the wake. This alteration effectively reduces the resistance of the tail car. Meanwhile, the micro-ramp vortex generator with its… More > Graphic Abstract