Open Access. Powered by Scholars. Published by Universities.®
- Keyword
-
- Air conditioning (3)
- Energy efficiency (2)
- Energy saving (2)
- Falling film (2)
- Variable speed (2)
-
- 3D CFD simulation (1)
- Adaptive control (1)
- Air-conditioning system (1)
- Anodized aluminum (1)
- Assessment method (1)
- Assessment system (1)
- Cold storage (1)
- Comparative study (1)
- Contact angle (1)
- Control efficiency (1)
- Controller (1)
- Correlation (1)
- Decision making (1)
- Defrosting and frost-free (1)
- Degree of superheat (1)
- Dehumidifier (1)
- Direct expansion air conditioning (1)
- Direct-expansion (1)
- Distributed energy system (1)
- District cooling system (1)
- Electrical Energy Reduction; Motor Driven Pump; Compton Effect; Industrial Energy Audit; IPMVP Option B (1)
- Electrochemistry (1)
- Energy storage (1)
- Falling film dehumidification (1)
- Falling film regeneration; internal heating; corrosion; surface energy; anodized aluminum plate (1)
- File Type
Articles 1 - 19 of 19
Full-Text Articles in Mechanical Engineering
Improving The Energy Efficiency Of Petrochemical Plant Operations: A Measurement And Verification Case Study Using A Balanced Wave Optimizer, Eve Man Hin Chan, Kar-Kit Chu, Hin-Fung Chow, Chi-Wing Tsang, Danny Chi Kuen Ho, Shuk-Kei Ho
Improving The Energy Efficiency Of Petrochemical Plant Operations: A Measurement And Verification Case Study Using A Balanced Wave Optimizer, Eve Man Hin Chan, Kar-Kit Chu, Hin-Fung Chow, Chi-Wing Tsang, Danny Chi Kuen Ho, Shuk-Kei Ho
Faculty of Science & Technology (THEi)
The Chinese petrochemical industry is facing pressure to meet strict targets of energy consumption and carbon emission reductions. Water pumps are the primary equipment used in most chemical and agrochemical industries sectors since water is commonly used for cooling and heating purposes, but these pumps also consume a large amount of energy. Other uses of water pumps in these industries include producing steam for heating, preparing reaction media or absorptive reagents, rinsing products, and distilling. As for the electrical components of the water pump systems, current technologies of variable frequency drives and superconducting transmission lines are unable to increase the …
Recycling Licoo2 With Methanesulfonic Acid For Regeneration Of Lithium-Ion Battery Electrode Materials., Bin Wang, Xin-Ye Lin, Yuanyuan Tang, Qiang Wang, Michael K.H. Leung, Xiao-Ying Lu
Recycling Licoo2 With Methanesulfonic Acid For Regeneration Of Lithium-Ion Battery Electrode Materials., Bin Wang, Xin-Ye Lin, Yuanyuan Tang, Qiang Wang, Michael K.H. Leung, Xiao-Ying Lu
Faculty of Science & Technology (THEi)
With the massive consumption of lithium-ion batteries in portable consumer electronics and electric vehicles, proper disposal of spent batteries is of paramount importance for sustainable development. In this study, biodegradable organic methanesulfonic acid (MSA) is investigated for the first time to leach valuable metals from waste LiCoO2 powders for battery material regeneration. Under the optimal conditions, leaching efficiencies of lithium and cobalt are achieved at nearly ∼100% and ∼100%, respectively. Comparison experiment indicates that MSA can achieve better leaching performance than previously reported organic acids (e.g. citric acid, malonic acid, succinic acid, oxalic acid) under the same conditions. Besides, strong …
Micro/Nanostructured Mnco2o4.5 Anodes With High Reversible Capacity And Excellent Rate Capability For Next Generation Lithium-Ion Batteries, Bin Wang, Shifeng Wang, Yuanyuan Tang, Chi-Wing Tsang, Jinchuan Dai, Michael K.H. Leung, Xiao-Ying Lu
Micro/Nanostructured Mnco2o4.5 Anodes With High Reversible Capacity And Excellent Rate Capability For Next Generation Lithium-Ion Batteries, Bin Wang, Shifeng Wang, Yuanyuan Tang, Chi-Wing Tsang, Jinchuan Dai, Michael K.H. Leung, Xiao-Ying Lu
Faculty of Science & Technology (THEi)
Lithium-ion batteries have already achieved great success in consumer electronics. However, the electrochemical characteristics of the existing electrodes have constrained their widespread applications in electric vehicles, which need technical demands of high energy density and fast charging. Thus, it is highly desirable to explore high-performance electrodes with high reversible capacity and excellent rate capability. In this study, micro/nanostructured MnCo2O4.5 anodes were synthesized by hydrothermal treatment with the presence of positively charged poly(diallyldimethylammonium chloride). Physicochemical property studies suggested that the as-prepared MnCo2O4.5 of 2–5 µm in diameter was mainly composed of numerous nanoneedles, which were further comprised of many inter-connected nanoparticles. …
Year-Round-Based Optimization Of High-Low Control In The Regenerative Indirect Evaporative Cooler (Riec), Huaxia Yan, Yi Chen, Weilong Zhang
Year-Round-Based Optimization Of High-Low Control In The Regenerative Indirect Evaporative Cooler (Riec), Huaxia Yan, Yi Chen, Weilong Zhang
Faculty of Science & Technology (THEi)
The performance of the regenerative indirect evaporative cooler (RIEC) highly depends on ambient temperature and humidity. To maintain indoor thermal comfort, proper control strategy is essential. Previous research indicates that high–low (H-L) control by using multispeed technology is superior to the conventional on–off control in terms of energy consumption and thermal comfort. Under H-L control, a fan switches between a high speed and a low speed. The high speed is determined by the peak load. However, the selection of low speed involves a great sense of subjectivity. Therefore, the influence of low speed on system performance is comprehensively investigated and …
A Novel 3d Simulation Model For Investigating Liquid Desiccant Dehumidification Performance Based On Cfd Technology., Tao Wen, Yimo Luo, Lu Lin
A Novel 3d Simulation Model For Investigating Liquid Desiccant Dehumidification Performance Based On Cfd Technology., Tao Wen, Yimo Luo, Lu Lin
Faculty of Science & Technology (THEi)
Previous 2D CFD simulation models fail to elaborate the actual simultaneous flow and dehumidification process in liquid desiccant cooling system. Accordingly, the present study successfully developed a novel 3D simulation model for investigating the liquid desiccant dehumidification performance of a falling film dehumidifier. The penetration mass transfer model was implemented in the simulation to account for the interfacial dehumidification process. Experimental system was built for the model validation and the results indicated that the newly developed 3D CFD model could predict the absolute moisture removal accurately with an average deviation of 7%. Parametric study revealed that the dehumidification performance was …
Flexible Integration Of Liquid Air Energy Storage With Liquefied Natural Gas Regasification For Power Generation Enhancement, Xiaohui She, Tongtong Zhang, Lin Cong, Xiaodong Peng, Chuan Li, Yimo Luo, Yulong Ding
Flexible Integration Of Liquid Air Energy Storage With Liquefied Natural Gas Regasification For Power Generation Enhancement, Xiaohui She, Tongtong Zhang, Lin Cong, Xiaodong Peng, Chuan Li, Yimo Luo, Yulong Ding
Faculty of Science & Technology (THEi)
Liquid Air Energy Storage (LAES) is one of the most promising energy storage technologies for achieving low carbon emissions. Our research shows that the LAES produces a considerable amount of excess heat that cannot be cost-effectively utilised in a standalone LAES system. On the other hand, the regasification of liquefied natural gas (LNG) often leads to waste of a large amount of high-grade cold energy. Therefore, this paper proposes the integration of the LAES with the LNG regasification process via a Brayton cycle (denoted as LAES-Brayton-LNG), where pressurized propane is used as both the heat transfer fluid and storage material …
A Review Of Renewable Energy Assessment Methods In Green Building And Green Neighborhood Rating Systems, Chong Zhang, Chengliao Cui, Ying Zhang, Jiaqi Yuan, Yimo Luo, Wenjie Gang
A Review Of Renewable Energy Assessment Methods In Green Building And Green Neighborhood Rating Systems, Chong Zhang, Chengliao Cui, Ying Zhang, Jiaqi Yuan, Yimo Luo, Wenjie Gang
Faculty of Science & Technology (THEi)
Green buildings and neighborhoods can help mitigate impacts of buildings on the environment, society and economy. Many rating systems or tools have been developed worldwide to assess and certificate green buildings or green neighborhoods. Renewable energy plays an important role in achieving green buildings/neighborhoods or zero energy buildings/neighborhoods by reducing fuel consumption and pollution emissions. However, substantial differences exist in assessing or quantifying the renewable energy in green building/neighborhood rating systems. This paper therefore provides a comprehensive review on renewable energy assessment methods adopted in green building/neighborhood rating systems, which would be very helpful to understand and then improve the …
Synthesis Of Sea Urchin-Like Nico2o4 Via Charge-Driven Self-Assembly Strategy For High Performance Lithium-Ion Batteries, Bin Wang, Chi-Wing Tsang, Ka Ho Li, Yuanyuan Tang, Yanping Mao, Xiao-Ying Lu
Synthesis Of Sea Urchin-Like Nico2o4 Via Charge-Driven Self-Assembly Strategy For High Performance Lithium-Ion Batteries, Bin Wang, Chi-Wing Tsang, Ka Ho Li, Yuanyuan Tang, Yanping Mao, Xiao-Ying Lu
Faculty of Science & Technology (THEi)
In this study, hydrothermal synthesis of sea urchin-like NiCo2O4 was successfully demonstrated by a versatile charge-driven self-assembly strategy using positively charged poly(diallydimethylammonium chloride) (PDDA) molecules. Physical characterizations implied that sea urchin-like microspheres of ~ 2.5 μm in size were formed by self-assembly of numerous nanoneedles with a typical dimension of ~ 100 nm in diameter. Electrochemical performance study confirmed that sea urchin-like NiCo2O4 exhibited high reversible capacity of 663 mAh g−1 after 100 cycles at current density of 100 mA g−1. Rate capability indicated that average capacities of 1085, 1048, 926, 642, 261, and 86 mAh g−1 could be achieved …
Study On The Performance Of Distributed Energy Systems Based On Historical Loads Considering Parameter Uncertainties For Decision Making., Chong Zhang, Xue Xue, Qianzhou Du, Yimo Luo, Wenjie Gang
Study On The Performance Of Distributed Energy Systems Based On Historical Loads Considering Parameter Uncertainties For Decision Making., Chong Zhang, Xue Xue, Qianzhou Du, Yimo Luo, Wenjie Gang
Faculty of Science & Technology (THEi)
Distributed energy systems (DESs) are becoming increasingly popular because of their high-energy efficiency and low pollution emissions. Accurate performance evaluation of such systems is critical for processes at the early design stages. However, there are considerable uncertainties in terms of the parameters used for performance evaluation and design optimization, including component efficiencies, customer demands, and energy markets. These uncertainties can significantly influence the performance of DESs. Without consideration of these uncertainties, the performance of DESs can be overestimated or underestimated, which leads to inaccurate decision-making. Therefore, this paper presents a comprehensive evaluation of the performance of DESs by considering uncertainties …
Comparative Study Of On-Off Control And Novel High- Low Control Of Regenerative Indirect Evaporative Cooler (Riec)., Yi Chen, Huaxia Yan, Hongxing Yang
Comparative Study Of On-Off Control And Novel High- Low Control Of Regenerative Indirect Evaporative Cooler (Riec)., Yi Chen, Huaxia Yan, Hongxing Yang
Faculty of Science & Technology (THEi)
The main characteristic of an indirect evaporative cooler (IEC) is its dependency on ambient air conditions. To ensure stable indoor temperature and provide better thermal comfort for the occupants, proper control strategy is essential. However, very limited studies report the controller used in IEC. Therefore, two control schemes are comparatively studied for regenerative indirect evaporative cooler (RIEC) application, including conventional on-off control and newly proposed high-low (H-L) control. Under on-off control scheme, the fans are either in operation at constant rated speeds or turned off if the indoor temperature is satisfied. While under H-L control scheme, the fans would be …
A New Capacity Controller For A Direct Expansion Air Conditioning System For Operational Safety And Efficiency., Yudong Xia, Huaxia Yan, Shiming Deng, Ming-Yin Chan
A New Capacity Controller For A Direct Expansion Air Conditioning System For Operational Safety And Efficiency., Yudong Xia, Huaxia Yan, Shiming Deng, Ming-Yin Chan
Faculty of Science & Technology (THEi)
For achieving a balance between the operational safety and efficiency of a variable speed direct expansion air conditioning system, a new capacity controller that can not only simultaneously control indoor air temperature and humidity, but also select an optimized degree of superheat setting to properly balance the operational safety and efficiency has been developed, by adding a control module to a previously developed capacity controller. The core of the control module was an artificial neural network based model representing the known relationship between the inherent operational characteristics and operational stability of a variable speed direct expansion air conditioning system. Using …
Development And Experimental Study Of A Novel Plate Dehumidifier Made Of Anodized Aluminum., Tao Wen, Lin Lu, Chuanshuai Dong, Yimo Luo
Development And Experimental Study Of A Novel Plate Dehumidifier Made Of Anodized Aluminum., Tao Wen, Lin Lu, Chuanshuai Dong, Yimo Luo
Faculty of Science & Technology (THEi)
The falling film dehumidifier is a key component in the liquid desiccant cooling system (LDCS). However, the most commonly used metals, such as steel and aluminum, can hardly resist the erosion of liquid desiccant. It greatly limits the fabrication of compact dehumidifiers and hinders the promotion of LDCS. The present study introduced a novel falling film dehumidifier which was made by the metal of anodized aluminum. Experiments were carried out to compare the dehumidification performance between ordinary aluminum dehumidifier and anodized one. The influences of air temperature, mass flow rate, inlet humidity and solution temperature, mass flow rate, temperature on …
Energy-Efficient And -Economic Technologies For Vapor Compression Refrigeration Systems: A Comprehensive Review., Xiaohui She, Lin Cong, Binjian Nie, Guanghui Leng, Hao Peng, Yi Chen, Xiaosong Zhang, Tao Wen, Hongxing Yang, Yimo Luo
Energy-Efficient And -Economic Technologies For Vapor Compression Refrigeration Systems: A Comprehensive Review., Xiaohui She, Lin Cong, Binjian Nie, Guanghui Leng, Hao Peng, Yi Chen, Xiaosong Zhang, Tao Wen, Hongxing Yang, Yimo Luo
Faculty of Science & Technology (THEi)
Vapor Compression Refrigeration Systems (VCRS) are widely used to provide cooling or freezing for domestic/office buildings, supermarkets, data centres, etc., which expend 15% of globally electricity and contribute to ∼10% of greenhouse gas emissions globally. It is reported that cooling demand is expected to grow tenfold by 2050. Therefore, it is critical to improve the efficiency of the VCRS. In this paper, a comprehensive review of advanced and hot technologies is conducted for the VCRS. These technologies include radiative cooling, cold energy storage, defrosting and frost-free, temperature and humidity independent control (THIC), ground source heat pump (GSHP), refrigerant subcooling, and …
Investigation On Solar Assisted Liquid Desiccant Dehumidifier And Evaporative Cooling System For Fresh Air Treatment., Yi Chen, Hongxing Yang, Yimo Luo
Investigation On Solar Assisted Liquid Desiccant Dehumidifier And Evaporative Cooling System For Fresh Air Treatment., Yi Chen, Hongxing Yang, Yimo Luo
Faculty of Science & Technology (THEi)
The widely used semi-centralized air conditioning (A/C) system consisting of independent fresh air system and fan coil system suffers from huge energy consumption, especially for fresh air treatment. Therefore, a liquid desiccant dehumidifier and regenerative indirect evaporative cooling (LDD-RIEC) system is proposed for fresh air treatment. The fresh air is handled by the LDD-RIEC system in which no electricity-intensive compressor involves. The hot and humid fresh air is firstly dehumidified by LDD and then sensibly cooled by RIEC. The thermal energy captured by solar collectors is used for desiccant solution regeneration. Indoor return air is cooled by fan coils of …
Further Development Of A Thermal Comfort Based Fuzzy Logic Controller For A Direct Expansion Air Conditioning System, Huaxia Yan, Yan Pan, Zhao Li, Shiming Deng
Further Development Of A Thermal Comfort Based Fuzzy Logic Controller For A Direct Expansion Air Conditioning System, Huaxia Yan, Yan Pan, Zhao Li, Shiming Deng
Faculty of Science & Technology (THEi)
The primary purpose of A/C is offering occupants with acceptable indoor thermal comfort levels. Thermal comfort is a complicated result of non-linear interactions between six parameters. However, many of current A/C systems solely control air temperature. Whenever anyone of the five parameters other than temperature varies significantly, an occupant may feel thermally uncomfortable. To address the issue, a comprehensive thermal comfort index should be used as regulator in A/C systems. One fuzzy logic controller is available. However, the approach to the fuzzy logic controller is complicated. In this paper, one previous established fuzzy logic controller is simplified for its real …
Experimental Study Of A Novel Subcooling Method Based On Liquid Desiccant Dehumidification For Vapor-Compression Refrigeration Systems., Xiaohui She, Yonggao Yin, Yimo Luo, Lindeman Brett, Dan Zhong, Xiaosong Zhang
Experimental Study Of A Novel Subcooling Method Based On Liquid Desiccant Dehumidification For Vapor-Compression Refrigeration Systems., Xiaohui She, Yonggao Yin, Yimo Luo, Lindeman Brett, Dan Zhong, Xiaosong Zhang
Faculty of Science & Technology (THEi)
Refrigerant subcooling could increase the refrigerating capacity and potentially improve the performance of refrigeration systems. In this paper, a novel subcooling method is experimentally studied for the first time in a hybrid vapor compression refrigeration system. In this system, condensation heat (~40 °C) is used to drive an integrated subcooling cycle to subcool the refrigerant leaving the condenser, which significantly increases the system performance. Changes in system performance are measured as functions of the following variables: the mass flow rates of the dehumidification air, ambient air, dehumidification solution, regeneration solution, and spraying water. Comparisons are made between the proposed system …
Investigation On The Regeneration Performance Of Liquid Desiccant By Adding Surfactant Pvp-K30., Tao Wen, Lin Lu, Chuanshuai Dong, Yimo Luo
Investigation On The Regeneration Performance Of Liquid Desiccant By Adding Surfactant Pvp-K30., Tao Wen, Lin Lu, Chuanshuai Dong, Yimo Luo
Faculty of Science & Technology (THEi)
The liquid desiccant cooling system (LDCS) is a promising alternative for the conventional vapor compression system due to its high energy efficiency. To enhance the mass transfer between the regeneration air and liquid desiccant in the regenerator, the paper firstly introduced a kind of surfactant called polyvinyl pyrrolidone (PVP-K30) which was added into the LiCl solution for better desiccant regeneration performance. The falling film characteristics and regeneration performance were investigated and compared with and without surfactant. The results indicated that the contact angle of desiccant solution on plate decreased from 58.5° to 28.0° by adding surfactant with 0.4% of concentration. …
Investigation On The Regeneration And Corrosion Characteristics Of An Anodized Aluminum Plate Regenerator., Tao Wen, Lin Lu, Hongxing Yang, Yimo Luo
Investigation On The Regeneration And Corrosion Characteristics Of An Anodized Aluminum Plate Regenerator., Tao Wen, Lin Lu, Hongxing Yang, Yimo Luo
Faculty of Science & Technology (THEi)
The traditional vapor compression cooling system (VCS) has been criticized for its heavy reliance on electricity consumption and limited control ability of humidity. Compared with the VCS, the liquid desiccant cooling system (LDCS) is more efficient by handling the sensible and latent load separately. The present study investigated the regeneration and corrosion characteristics of an anodized aluminum plate regenerator for the first time. Comparative tests were conducted to present the regeneration and corrosion characteristics of the normal and anodized regenerator. The influence of internal heating on the regeneration performance was also identified. The results showed that the corrosion rate was …
Inherent Operational Characteristics Aided Fuzzy Logic Controller For A Variable Speed Direct Expansion Air Conditioning System For Simultaneous Indoor Air Temperature And Humidity Control., Huaxia Yan, Yudong Xia, Xiangguo Xu, Shiming Deng
Inherent Operational Characteristics Aided Fuzzy Logic Controller For A Variable Speed Direct Expansion Air Conditioning System For Simultaneous Indoor Air Temperature And Humidity Control., Huaxia Yan, Yudong Xia, Xiangguo Xu, Shiming Deng
Faculty of Science & Technology (THEi)
Direct expansion air conditioning systems are widely installed in small-to medium- scale buildings due to their advantages of simple configuration, high energy efficiency and low cost to own and maintain. The two main targets of air conditioning operation include improving the system operational efficiency and energy efficiency. Stable system operational efficiency is directly related with the operation of electronic expansion valves and degree of superheat at the outlet of evaporator. In this paper, an adaptive DS controller is developed to improve the system operational efficiency based the experimental performance of a DX A/C system and reported. The adaptive DS controller …