Energy Engineering

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Energy Engineering

ISSN: 0199-8595 (print)
ISSN: 1546-0118 (online) Publication Frequency: Bi-monthly

About the Journal

Energy Engineering is a bi-monthly peer-reviewed publication. The journal invites researchers, engineers, scientists, technologists, planners, and policy makers to present their original research results and findings on all important energy topics.

Indexing and Abstracting

Ei Compendex; WorldCat; Scopus...

Previously published by Taylor&Francis Group (https://www.tandfonline.com/toc/uene20/current), Energy Engineering starts to be published by Tech Science Press from 2020 and supports Open Access Policy.
From 1st May 2020, an Article Processing Charge (APC) of $600 US dollars applies to papers accepted after peer review.

Current Issue - Vol.118, No.2, 2021 Most Viewed

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ARTICLE
A Novel Single Switch High Gain DC-DC Converter Topology for Renewable Energy Systems
G. Indira Kishore¹, M. Premkumar^1,*, Ramesh Kumar Tripathi², Chandra Sekhar Nalamati²
Energy Engineering, Vol.118, No.2, pp. 199-209, 2021, DOI:10.32604/EE.2021.014079
（This article belongs to this Special Issue: Advancements in Renewable Energy Systems with AI, Big Data, BlockChain, IoT, and Machine Learning Applications)
Abstract Renewable energy with sources such as photovoltaic (PV) or fuel cells can be utilized for the generation of electrical power. But these sources generate fewer voltage values and therefore require high gain converters to match with DC bus voltage in microgrids. These high gain converters can be implemented with switched capacitors to meet the required DC bus voltage. Switched capacitors operate in a series and parallel combination during switching operation and produce high static gain, limits reverse voltage that appears across the components. A novel converter is proposed that satisfies all the features such as high voltage gain, only one… More
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ARTICLE
Performance Assessment of Heat Exchangers for Process Heat Integration
Fenwicks Shombe Musonye^1,*, Hiram Ndiritu², Robert Kinyua³
Energy Engineering, Vol.118, No.2, pp. 211-224, 2021, DOI:10.32604/EE.2021.013890
Abstract Pinch Analysis is an attractive solution for reduction of thermal energy costs in thermo-chemical industries. In this approach, maximum internally recoverable heat is determined and a heat exchange network is designed to meet the recovery targets. The thermal performance of a heat exchanger over its lifetime is however a concern to industries. Thermal performance of a heat exchanger is affected by many factors which include the physical properties of the shell and tube materials, and the chemical properties of the heat transfer fluid. In this study, thermal performance of shell and tube heat exchangers designed to meet heat recovery targets… More
Views:243 Downloads:138 Download PDF

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ARTICLE
Parameter Scaling of the Aerodynamic Breakup of the Acoustic Levitated Droplets in an Air Jet Flow
Yanju Wei^1,*, Shengcai Deng¹, Jie Zhang¹, Yajing Yang², Hao Chen³
Energy Engineering, Vol.118, No.2, pp. 225-235, 2021, DOI:10.32604/EE.2021.012416
Abstract The aerodynamic breakup of the droplet has been intensely studied in this paper. We aim to establish a unified relationship between dimensionless kinematic parameters such as displacement, spreading diameter, Weber number, time, and so on. The breakup characteristics of the acoustic levitated ethanol droplet are experimentally investigated when exposed to an air jet flow. The breakup phenomenons were recorded with a high-speed camera. The breakup characteristics were analyzed, and the physical models of the moving and transforming behaviors were established to explain the breakup mechanisms. We found that the displacement of the windward side of the droplet follows free acceleration… More
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ARTICLE
Model Predictive Yaw Control Using Fuzzy-Deduced Weighting Factor for Large-Scale Wind Turbines
Shuowang Zhang¹, Lingxiang Huang^1,*, Dongran Song^2,*, Ke Xu¹, Xuebing Yang¹, Xiaoping Song¹
Energy Engineering, Vol.118, No.2, pp. 237-250, 2021, DOI:10.32604/EE.2021.014269
（This article belongs to this Special Issue: Wind Energy Development and Utilization)
Abstract Yaw control system plays an important role in helping large-scale horizontal wind turbines capture the wind energy. To track the stochastic and fast-changing wind direction, the nacelle is rotated by the yaw control system. Therein, a difficulty consists in the variation speed of the wind direction much faster than the rotation speed of the nacelle. To deal with this difficulty, model predictive control has been recently proposed in the literature, in which the previewed wind direction is employed into the predictive model, and the estimated captured energy and yaw actuator usage are two contradictive objectives. Since the performance of the… More
Views:135 Downloads:64 Download PDF

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ARTICLE
Analysis of Electromagnetic Performance of Modulated Coaxial Magnetic Gears Used in Semi-Direct Drive Wind Turbines
Jungang Wang^1,*, Liqun Qian¹, Shuairui Xu¹, Ruina Mo²
Energy Engineering, Vol.118, No.2, pp. 251-264, 2021, DOI:10.32604/EE.2021.014143
（This article belongs to this Special Issue: Wind Energy Development and Utilization)
Abstract Wind turbine is a key device to realize the utilization of wind energy, and it has been highly valued by all countries. But the mechanical gear transmission of the existing wind power device has the disadvantages of high vibration and noise, high failure rate, and short service time. Magnetic field modulation electromagnetic gear transmission is a new non-contact transmission method. However, the conventional modulation magnetic gear has low torque density and torque defects with large fluctuations. In order to overcome the gear transmission problems of the existing semi-direct drive wind power generation machinery and improve the electromagnetic performance of the… More
Views:112 Downloads:58 Download PDF

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ARTICLE
Adaptive Fractional-Order PID Control for VSC-HVDC Systems via Cooperative Beetle Antennae Search with Offshore Wind Integration
Pulin Cao, Haoran Fan, Zilong Cai^*
Energy Engineering, Vol.118, No.2, pp. 265-284, 2021, DOI:10.32604/EE.2021.014513
（This article belongs to this Special Issue: Wind Energy Development and Utilization)
Abstract Since the voltage source converter based high voltage direct current (VSC-HVDC) systems owns the features of nonlinearity, strong coupling and multivariable, the classical proportional integral (PI) control is hard to obtain content control effect. Hence, a new perturbation observer based fractional-order PID (PoFoPID) control strategy is designed in this paper for (VSC-HVDC) systems with offshore wind integration, which can efficiently boost the robustness and control performance of entire system. Particularly, it employs a fractional-order PID (FoPID) framework for the sake of compensating the perturbation estimate, which dramatically boost the dynamical responds of the closed-loop system, and the cooperative beetle antennae… More
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ARTICLE
Demand Responsive Market Decision-Makings and Electricity Pricing Scheme Design in Low-Carbon Energy System Environment
Hongming Yang^1,*, Qian Yu¹, Xiao Huang¹, Ben Niu², Min Qi³
Energy Engineering, Vol.118, No.2, pp. 285-301, 2021, DOI:10.32604/EE.2021.013734
Abstract The two-way interaction between smart grid and customers will continuously play an important role in enhancing the overall efficiency of the green and low-carbon electric power industry and properly accommodating intermittent renewable energy resources. Thus far, the existing electricity pricing mechanisms hardly match the technical properties of smart grid; neither can they facilitate increasing end users participating in the electricity market. In this paper, several relevant models and novel methods are proposed for pricing scheme design as well as to achieve optimal decision-makings for market participants, in which the mechanisms behind are compatible with demand response operation of end users… More
Views:105 Downloads:54 Download PDF

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ARTICLE
An Advanced Approach for Improving the Prediction Accuracy of Natural Gas Price
Quanjia Zuo¹, Fanyi Meng^1,*, Yang Bai²
Energy Engineering, Vol.118, No.2, pp. 303-322, 2021, DOI:10.32604/EE.2021.013239
Abstract As one of the most important commodity futures, the price forecasting of natural gas futures is of great significance for hedging and risk aversion. This paper mainly focuses on natural gas futures pricing which considers seasonality fluctuations. In order to study this issue, we propose a modified approach called six-factor model, in which the influence of seasonal fluctuations are eliminated in every random factor. Using Monte Carlo method, we first assess and comparative analyze the fitting ability of three-factor model and six-factor model for the out of sample data. It is found that six-factor model has better performance than three-factor… More
Views:101 Downloads:51 Download PDF

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ARTICLE
An Analysis of the Operation Mechanism of Chemical Industry Park Ecosystem Based on Theory of Ecological Organization
Bilin Xu, Mei Han^*
Energy Engineering, Vol.118, No.2, pp. 323-339, 2021, DOI:10.32604/EE.2021.013384
Abstract Based on the theory of ecological organization, this paper analyzes the operation mechanism of chemical industry park (CIP) ecosystem by means of dynamic simulation. The research shows that the CIP ecosystem is a complex ecological system whose operation mechanism includes two levels, namely individual enterprises and ecosystem. At the level of individual enterprise, there are competition, symbiosis, invasion and other interactions between enterprises in the CIP ecosystem. Through the pre-determined judgment of the competition effect coefficient and the symbiosis effect coefficient, we calculate how the enterprises influence each other, and then generate their respective operation paths, and finally realize the… More
Views:219 Downloads:114 Download PDF

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ARTICLE
A Novel Polymorphic Topology with Hybrid Control Strategy Based LLC Resonant Converter for Ultra-Wide Input Voltage Range Applications
Chi Zhang, Yong Shi^*, Xuwei Gui
Energy Engineering, Vol.118, No.2, pp. 341-361, 2021, DOI:10.32604/EE.2021.014229
Abstract To realize effective utilization of renewable energy sources, a novel polymorphic topology with hybrid control strategy based LLC resonant converter was analyzed and designed in this paper. By combining the merits of a full bridge LLC resonant converter, three-level half bridge LLC resonant converter, and variable frequency control mode, the converter realizes an intelligent estimation of input voltage by automatically changing its internal circuit topology. Under this control strategy, different input voltages determine different operation modes. This is achieved in full bridge LLC mode when the input voltage is low. If the input voltage rises to a certain level, it… More
Views:429 Downloads:208 Download PDF

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ARTICLE
Impact of Greenization on the Marginal Utility of Intensity of Carbon Emissions and Factors Affecting it in China
Yu Liu¹, Ruiting Jiao¹, Liyao Zhao¹, Kai Liu^1,2,*
Energy Engineering, Vol.118, No.2, pp. 363-378, 2021, DOI:10.32604/EE.2021.013472
（This article belongs to this Special Issue: Energy Systems Management and Climate Change)
Abstract The impact of greenization on the marginal utility of the intensity of carbon emissions in China and factors influencing this relationship are explored in this study. China’s level of greenization is evaluated by using an index system developed based on the comprehensive index method. The intensity of carbon emissions is determined by using the standards for the coefficients of conversion of coal equivalent and coefficients of carbon emission. The impact of greenization on the marginal utility of the intensity of carbon emissions is then evaluated by using an elastic formula and factors affecting this relationship are verified by regression analysis.… More
Views:221 Downloads:107 Download PDF

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ARTICLE
Internet of Things Enabled Intelligent Energy Management and Control System for Heavy Equipment Industrial Park and Fuzzy Assessment of Its Schemes
Jia Zhu^*
Energy Engineering, Vol.118, No.2, pp. 379-397, 2021, DOI:10.32604/EE.2021.014178
Abstract In order to solve the problems of poor information flow, low energy utilization rate and energy consumption data reuse in the heavy equipment industrial park, the Internet of Things (IoT) technology is applied to construct the intelligent energy management and control system (IEMCS). The application architecture and function module planning are analyzed and designed. Furthermore, the IEMCS scheme is not unique due to the fuzziness of customer demand and the understanding deviation of designer to customer demand in the design stage. Scheme assessment is of great significance for the normal subsequent implementation of the system. A fuzzy assessment method for… More
Views:96 Downloads:60 Download PDF

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ARTICLE
Experimental Research of the Radiator Thermal Performance Test Equipment and Its Application in Heating System
Lian Zhang^1,2,3,*, Linjun Fan⁴, Xin Xu⁵, Baowen Cao¹, Heng Zhang², Lihong Song³
Energy Engineering, Vol.118, No.2, pp. 399-410, 2021, DOI:10.32604/EE.2021.012647
Abstract Radiator thermal performance test equipment plays a key role in the processing of developing a new type of heat radiator and its application products. The precise of temperature controlling, temperature measuring and flow measuring are the vital factors for a radiator thermal performance test equipment. Based on the above background, this paper improves the measurement and control system of radiator thermal performance test equipment, which improves the accuracy of the radiator thermal performance test equipment. This paper also optimizes the software and hardware system simultaneously so as to improve the precision of the auto-test system of test equipment. The flow… More
Views:198 Downloads:97 Download PDF

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ARTICLE
Development of Environmentally Friendly and Energy Efficient Refrigerants for Refrigeration Systems
Piyanut Saengsikhiao¹, Juntakan Taweekun^1,2,*, Kittinan Maliwan², Somchai Sae-ung², Thanansak Theppaya²
Energy Engineering, Vol.118, No.2, pp. 411-433, 2021, DOI:10.32604/EE.2021.012860
Abstract This paper presents the improvement of eco-friendly and power consumption saving refrigerants for refrigeration systems. The novel azeotropic refrigerant mixtures of HFCs and HCs can replace refrigeration systems, and using the R134, R32, R125, and R1270 refrigerants in several compositions found using the decision tree function of the RapidMiner software (which came first in the KDnuggets annual software poll). All refrigerant results are mixed of POE, which is A1 classification refrigerant, non-flammable, and innocuous refrigerant, and using REFPROP software and CYCLE_D-HX software are under the CAN/ANSI/AHRI540 standards. The boiling point of the new refrigerant mix R-No.595 is 4.58%, lower than… More
Views:122 Downloads:65 Download PDF

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ARTICLE
Experimental Study on Flow and Heat Transfer Characteristics of Nanofluids in a Triangular Tube at Different Rotation Angles
Cong Qi^1,2,*, Chengchao Wang^1,2, Jinghua Tang^1,2, Dongtai Han²
Energy Engineering, Vol.117, No.2, pp. 63-78, 2020, DOI:10.32604/EE.2020.010433
Abstract Because of the poor thermal performance of ordinary tubes, a triangular tube was used to replace the smooth channel in the heat transfer system, and nanofluids were used to take the place of ordinary fluids as the heat transfer medium. High stability nanofluids were prepared, and an experimental set on flow and heat exchange was established. Effects of triangular tube rotation angles (α = 0°, 30°, 60°) as well as mass fractions of nanofluids (ω = 0.1%, 0.3%, 0.5%) on heat exchange and flow performance were experimentally considered at Reynolds numbers (Re = 800–8000). It was shown that the triangular… More
Views:1462 Downloads:884 Download PDF

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ARTICLE
Unsteady Natural Convection within an Attic-Shaped Space Subject to Sinusoidal Heat Flux on Inclined Walls
Suvash C. Saha^1,*, Ali M. Sefidan², Atta Sojoudi³
Energy Engineering, Vol.117, No.1, pp. 1-17, 2020, DOI:10.32604/EE.2020.010418
Abstract Free convection inside an attic enclosure in which sinusoidal heat flux applied on the inclined walls and a constant temperature applied on the base wall has been investigated numerically to demonstrate the primary flow characteristics and heat transfer within the attic enclosure over daily routine cycles. To solve the governing equations, the finite volume technique has been utilized. After performing the grid independency and time step size tests, the roles of Rayleigh number (Ra) and the attic aspect ratio (AR) on the unsteady flow structure and heat transfer phenomenon are explained for a constant Prandtl number (0.72) for the air.… More
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ARTICLE
Performance and Cost Analysis of Energy Production from Offshore Wind Turbines
Haytham Ayoub, Ehab Hussein Bani-Hani^*
Energy Engineering, Vol.117, No.1, pp. 41-47, 2020, DOI:10.32604/EE.2020.010412
Abstract Offshore wind turbine is analyzed theoretically and experimentally for improving wind energy harvesting. The energy produced is calculated at different wind speeds. The wind speed curve is generated by measuring the wind speed on daily base for one year. Curves that show the power extraction for experimental study and from the theoretical calculations are generated. The energy production investigation is expanded over a period of 15 years after comparing the annual energy production in theory and practice. The study shows the cost of electricity over the same time period assuming different interest rates. Three time intervals are shown that are… More
Views:1336 Downloads:726 Download PDF

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ARTICLE
Experimental Study on Modal and Harmonic Analysis of Small Wind Turbine Blades Using NACA 63-415 Aerofoil Cross-Section
Ajay Veludurthi¹, Venkateshwarlu Bolleddu^2,*
Energy Engineering, Vol.117, No.2, pp. 49-61, 2020, DOI:10.32604/EE.2020.010666
Abstract This work focused on modal and harmonic analysis of small wind turbine blades taken from the NACA 63415 series. The sandwich structure type composite blade is fabricated from GFRP and epoxy with Uni-vinyl hard foams of different alignments as stiffeners. In this work, the modal and harmonic analysis of different varieties of blades like solid, hallow and rectangular alignment blades is carried out by the finite element method using ANSYS 18.1 software. From Finite Element Analysis, the natural frequencies, amplitudes and mode shapes are obtained. Based on the working principle of wind turbine blades, the boundary conditions are applied. The… More
Views:1334 Downloads:1227 Download PDF

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ARTICLE
Research on the Measurement and Countermeasure of Coal Overcapacity in China: Based on Panel Data of 25 Provinces in China
Rijia Ding¹, Xingyao Zhou^1,*, Rui Zhang¹, Wanqiu Lu²
Energy Engineering, Vol.117, No.1, pp. 27-39, 2020, DOI:10.32604/EE.2020.010372
Abstract Coal is the main energy source in China. At present, the coal overcapacity is still serious in China. Accurately measuring the degree of China’s coal overcapacity can scientifically resolve the overcapacity, and is the premise of guiding the healthy development of coal industry and energy system. Using the translog cost function and the panel data of coal industry in all provinces of China from 2002 to 2011 and from 2012 to 2016, the research measures and compares the coal production capacity of “golden decade” and “cold winter” in China. The results show that: (1) The change of coal production capacity… More
Views:1288 Downloads:643 Download PDF

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ARTICLE
Research on the Influencing Rules of Gas Hydrate Emission Dissipation Coefficient Based on Subspace Spectrum Clustering
Geng Guo^1,*, Leiwen Chen¹, Ji Li², Shu Yan³, Wenxiang Wu⁴, Lingxu Li⁵, Hongda Li⁶
Energy Engineering, Vol.117, No.2, pp. 79-88, 2020, DOI:10.32604/EE.2020.010529
Abstract Featured by high energy density, low combustion pollution and large quantity, natural gas hydrate has become one of the research hotspots in Sanlutian Field of Muri Coalfield since 2008, when China first drilled natural gas hydrate samples in the permafrost area of Qilian Mountains, Qinghai-Tibet Plateau. However, the study on the controlling factors of gas hydrate accumulation is still shallow, which hinders the exploration and development of natural gas hydrate resources. The controlling factors of gas hydrate accumulation mainly include temperature and pressure conditions, gas source conditions, sedimentary conditions and structural conditions, among which structural conditions are the important one.… More
Views:1260 Downloads:612 Download PDF