Hasan S. Majdi^a,*, Azher M. Abed^b, Laith J. Habeeb^c

Frontiers in Heat and Mass Transfer, Vol.17, pp. 1-7, 2021, DOI:10.5098/hmt.17.6

Abstract The present work presents and analyzes the results acquired from outdoor experimental measurements of a solar latent heat storage unit integrated with built-in thermal energy storage at the presence and absence of porous media. The tank consists of a porous media part, a packed of glass beds, and the fluid flowing through the void space surrounding the porous glass beds. The porous tanks were filled by 1.68 mm glass beds to form bed heights (h) of 10 and 20 cm. Results show that the maximum thermal storage of 110 min is achieved in hot flow rate qh=4 LPM, cold flow… More >

Kun Zhang^a,b,* , Zhiyong Li^a,b, Jia Yao^a,b

Frontiers in Heat and Mass Transfer, Vol.19, pp. 1-8, 2022, DOI:10.5098/hmt.19.5

Abstract Detailed numerical analysis is presented for heat transfer characteristics of charging or discharging process in phase change thermal energy storage unit with inner corrugated tube. The results indicated that the charging or discharging rate of phase change material (PCM) for the case of inner corrugated tube is obviously higher than that in unit with inner plain tube due to the increasing heat transfer surface. The heat transfer rate increase with the increasing mass flow rate. However, when the mass flow rate of heat transfer fluid (HTF) is greater than 0.0315kg/s, the charge and discharge time can not be obviously shorten… More >

Yiding Cao

Frontiers in Heat and Mass Transfer, Vol.19, pp. 1-12, 2022, DOI:10.5098/hmt.19.1

Abstract This paper introduces utility-scale underground hot water storage (USUHWS) systems and evaluates their performance to enable renewable energy sources to produce dispatchable utility-scale power or supply heat with minimized interruption and impact by weather conditions. The USUHWS systems could retain the thermal energy content of the stored hot water for years so that renewable energy can be extracted and stored at any time year-round and be used whenever needed. Another major objective of this paper is to introduce hot-water power and heat internets to interconnect storage systems, power plants, energy sources, and various water and heat users to efficiently manage… More >

Ghaith Yahya Abusaibaa^a , Kamaruzzaman Sopian^a,*, Hasila Jarimi^a , Adnan Ibrahim^a, Saffa Riffat^b

Frontiers in Heat and Mass Transfer, Vol.20, pp. 1-6, 2023, DOI:10.5098/hmt.20.21

Abstract This study will demonstrate the performance of a photovoltaic (PV) powered vapour compression cooling system connected to a Phase Change Material (PCM) storage tank. Three options were studied, namely (a) PV vapour compression with a PCM storage tank and an air-conditioned room with chilled water circulation with transparent membrane/desiccant; (b) PV vapour compression with a PCM storage tank and an air-conditioned room with chilled air dehumidification; and (c) PV vapour compression with a PCM storage tank and an air-conditioned room chilled by combined water circulation, a transparent membrane/desiccant, and air duct dehumidification. Simulation using TRNSYS, TRNBuild, and EES programmes has… More >

Sanghyuck Nam¹, Jaehwan Lee², Kyoungchan Kim³, Mingyu Jo¹, Sangoh Park^1,*

Computer Systems Science and Engineering, Vol.46, No.3, pp. 3457-3469, 2023, DOI:10.32604/csse.2023.035428

Abstract Recently, research on a distributed storage system that efficiently manages a large amount of data has been actively conducted following data production and demand increase. Physical expansion limits exist for traditional standalone storage systems, such as I/O and file system capacity. However, the existing distributed storage system does not consider where data is consumed and is more focused on data dissemination and optimizing the lookup cost of data location. And this leads to system performance degradation due to low locality occurring in a Wide Area Network (WAN) environment with high network latency. This problem hinders deploying distributed storage systems to… More >

Yunfan Huang¹, Qingquan Lv², Zhenzhen Zhang², Haiying Dong^1,*

Energy Engineering, Vol.120, No.6, pp. 1401-1420, 2023, DOI:10.32604/ee.2023.027365

Abstract The virtual synchronous generator (VSG) can simulate synchronous machine’s operation mechanism in the control link of an energy storage converter, so that an electrochemical energy storage power station has the ability to actively support the power grid, from passive regulation to active support. Since energy storage is an important physical basis for realizing the inertia and damping characteristics in VSG control, energy storage constraints of the physical characteristics on the system control parameters are analyzed to provide a basis for the system parameter tuning. In a classic VSG control, its virtual inertia and damping coefficient remain unchanged. When the grid… More >

Wei Chen¹, Na Sun¹, Zhicheng Ma², Wenfei Liu², Haiying Dong^1,*

Energy Engineering, Vol.120, No.6, pp. 1445-1464, 2023, DOI:10.32604/ee.2023.027158

Abstract To address the frequency fluctuation problem caused by the power dynamic imbalance between the power system and the load when a large number of new energy sources are connected to the grid, a two-layer fuzzy control strategy is proposed for the participation of the energy storage battery system in FM. Firstly, considering the coordination of FM units responding to automatic power generation control commands, a comprehensive allocation strategy of two signals under automatic power generation control commands is proposed to give full play to the advantages of two FM signals while enabling better coordination of two FM units responding to… More > Graphic Abstract

Siwei Han^1,*, Xianglong Li², Wei Zhao¹, Linyu Wang¹, Anqi Liang², Shuang Zeng²

Energy Engineering, Vol.120, No.6, pp. 1421-1444, 2023, DOI:10.32604/ee.2023.027094

Abstract Photovoltaics, energy storage, direct current and flexibility (PEDF) are important pillars of achievement on the path to manufacturing nearly zero energy buildings (NZEBs). HVAC systems, which are an important part of public buildings, play a key role in adapting to PDEF systems. This research studied the basic principles and operational control strategies of a DC inverter heat pump using a DC distribution network with the aim of contributing to the development and application of small DC distribution systems. Along with the characteristics of a DC distribution network and different operating conditions, a DC inverter heat pump has the ability to… More >

Feng Zhao, Chengrui Xiao^*, Xiaoqiang Chen, Ying Wang

Energy Engineering, Vol.120, No.6, pp. 1353-1370, 2023, DOI:10.32604/ee.2023.025976

Abstract With the penetration of a large number of photovoltaic power generation units and power electronic converters, the DC microgrid shows low inertia characteristics, which might affect the stable operation of the microgrid in extreme cases. In order to enhance the “flexible features” of the interface converter connected to the DC bus, a control strategy of DC microgrid with photovoltaic and energy storage based on the virtual DC generator (VDCG) is proposed in this paper. The interface converters of the photovoltaic power generation system and the energy storage system simulates the inertia and damping characteristics of the DC generator to improve… More >

Xinyi Qing^1,3, Baopeng Ye², Yuanquan Shi^1,3, Tao Li^4,*, Yuling Chen⁴, Lei Liu¹

CMC-Computers, Materials & Continua, Vol.75, No.2, pp. 3607-3624, 2023, DOI:10.32604/cmc.2023.037532

Abstract Due to its decentralized, tamper-proof, and trust-free characteristics, blockchain is used in the Internet of Things (IoT) to guarantee the reliability of data. However, some technical flaws in blockchain itself prevent the development of these applications, such as the issue with linearly growing storage capacity of blockchain systems. On the other hand, there is a lack of storage resources for sensor devices in IoT, and numerous sensor devices will generate massive data at ultra-high speed, which makes the storage problem of the IoT enabled by blockchain more prominent. There are various solutions to reduce the storage burden by modifying the… More >