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  • 201.
    Yuting, Tan
    et al.
    Royal Institute of Technology, Sweden.
    Nookuea, Worrada
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Thorin, Eva
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Royal Institute of Technology, Stockholm, Sweden.
    Property Impacts on Plate-fin Multi-stream Heat Exchanger (Cold Box) Design in CO2 Cryogenic Process: Part II. Evaluation of Viscosity and Thermal Conductivity Models2017Inngår i: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 105, s. 4595-4600Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Viscosity and thermal conductivity are key transport properties in the design of plate-fin multi-stream heat exchanger in CO2 cryogenic processes. It is necessary to evaluate the reliabilities of viscosity and thermal conductivity models. In addition, the differences in design of multi-stream heat exchanger by using different property models need to be studied as well. In this paper, viscosity models and thermal conductivity models of CO2 mixtures with non-condensable gas impurities were evaluated separately by comparison with existing experimental data. Recommendations were given on model selections and their impact on the design of plate-finmulti-stream heat exchanger were analyzed.

    The results show that for viscosity, the uncertainty range of Wilke’s model is the smallest with a maximum absolute deviation of 6.1%. This model is therefore recommended to be used. For thermal conductivity, GERG model, with a maximum absolute deviation of 8.7% is preferred. The choice of thermal conductivity model has a noticeabl eimpact on the plate-fin multi-stream heat exchanger design, and the maximum deviation by using different thermal conductivity models is 7.5%

  • 202.
    Zhang, Q.
    et al.
    Academy of China Energy Strategy, China University of Petroleum-Beijing, Changping, Beijing, China.
    Li, Y.
    Academy of China Energy Strategy, China University of Petroleum-Beijing, Changping, Beijing, China.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Wang, G.
    Academy of China Energy Strategy, China University of Petroleum-Beijing, Changping, Beijing, China.
    Chen, S.
    Academy of China Energy Strategy, China University of Petroleum-Beijing, Changping, Beijing, China.
    Study on the Impacts of the LNG Market Reform in China using a SVM based Rolling Horizon Stochastic Game Analysis2017Inngår i: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 105, s. 3850-3855Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Natural gas is expected to play a much more important role in China in future decades and its market reform is crucial for its fast market penetration. At present, the main gas fields, pipeline and Liquefied Natural Gas (LNG) infrastructure are monopolized by the state owned big companies, and one of the important market reform policies is to open the LNG import rights to small private companies or traders. Therefore, in the present study, a Game Analysis Model is proposed to analyze and compare the impacts of different market structures on infrastructure deployment and social welfare. Moreover, a Support Vector Machine (SVM) based rolling horizon stochastic method has been adopted in the model to simulate the real LNG price fluctuations. The results indicate that, with the third part access (TPA) entrance into LNG market, the construction of LNG infrastructure will be promoted and more gas will be provided with lower prices, and thus the total social welfare will be improved greatly. 

  • 203.
    Zhang, Q.
    et al.
    China University of Petroleum-Beijing, Beijing, China .
    Mclellan, B. C.
    Kyoto University, Kyoto, Japan.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    An integrated scenario analysis for future zero-carbon energy system2015Inngår i: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 39, nr 7, s. 993-1010Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An integrated scenario analysis methodology has been proposed for zero-carbon energy system in perspectives of social-economy, environment and technology. By using the methodology, service demands in all sectors were estimated based on social-economic data, and then the best technology and energy mixes were obtained to meet the service demands. The methodology was applied to Japan toward zero-carbon energy system out to the year of 2100, and three different scenarios of nuclear power development are considered in light of the Fukushima accident: (i) no further introduction of nuclear, (ii) fixed portion and (iii) no limit of nuclear. The results show that, zero-carbon energy scenario can be attained in the year 2100 when electricity will supply 75% of total energy consumption, and three power generation scenarios were proposed, 30% renewable and 70% gas-carbon capture and storage (CCS) in Scenario 1, respective one-third nuclear, renewable and gas-CCS in Scenario 2, and 60% nuclear power, 20% renewable and 10% gas-CCS in Scenario 3. Finally, Scenario 2 is rated as the most balanced scenario by putting emphasis on the availability of diversified power source, considering the inter-comparison of the three scenarios from the four aspects of cost, CO<inf>2</inf> emission, risk and diversity. 

  • 204.
    Zhang, Qi
    et al.
    China Univ Petr, Acad Chinese Energy Strategy, Beijing 102249, Peoples R China..
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Mclellan, Benjamin
    Kyoto Univ, Grad Sch Energy Sci, Kyoto 6068501, Japan..
    An Integrated Scenario Analysis for Future Zero-Carbon Energy System2014Inngår i: INTERNATIONAL CONFERENCE ON APPLIED ENERGY, ICAE2014 / [ed] Yan, J Lee, DJ Chou, SK Desideri, U Li, H, ELSEVIER SCIENCE BV , 2014, s. 2801-2804Konferansepaper (Fagfellevurdert)
    Abstract [en]

    An integrated scenario analysis methodology has been proposed for zero-carbon energy system in perspectives of social-economy, environment and technology. In the methodology, firstly various service demands were estimated based on social-economic data, and best technology and energy mixes were obtained using the optimization model to meet the service demand. The methodology has been applied to Japan toward zero-carbon energy system out to 2100. The results show that, in the end user side, zero-carbon energy scenario was obtained based on 75% on electricity and three power generation scenarios were proposed, 30% renewable and 70% gas-CCS in scenario 1, respective one third nuclear, renewable and gas-CCS in scenario 2, and 60% nuclear power, 20% renewable and 10% gas-CCS in scenario 3. Finally, the scenario 2 with balanced diversity in nuclear, renewable and gas-CCS was recommended based on comprehensive inter-comparisons. The feasibility of the proposed methodology has been demonstrated. (C) 2014 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/).

  • 205.
    Zhang, Qi
    et al.
    China University of Petroleum.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Zhu, Lijing
    China University of Petroleum.
    Campana, Pietro Elia
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Lu, Huihui
    China University of Petroleum.
    Wallin, Fredrik
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Sun, Qie
    Shandong University.
    Factors influencing the economics of public charging infrastructures for EV: A review2018Inngår i: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 97, s. 500-509Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Growing concerns about energy conservation and the environmental impacts of greenhouse gas emissions over the world have promoted the development of the electric vehicles (EVs) market. However, one of the biggest barriers in the development of the EV market is the lack of the public charging infrastructure. This paper reviews the factors that can directly and indirectly influence the economics of the public charging infrastructure. The knowledge gaps, barriers and opportunities in the development of the charging infrastructure have been identified and analyzed. In order to promote the development of the public charging infrastructure, more research efforts should be paid on the impacts of psychological factors of customers and the technical development of charging infrastructures and EV batteries. The government support has been proved to play an important role, so that how the government policy can be tailored for the development of the charging infrastructure market should receive more attentions. In addition, the charging price as an endogenous factor should be considered more carefully in modelling the charging infrastructure market. New business models are also urgently needed to accelerate the future development of the public charging infrastructure.

  • 206.
    Zhang, Qi
    et al.
    China University of Petroleum, China.
    Li, Zhang
    China University of Petroleum, China.
    Wang, Ge
    China University of Petroleum, China.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Study on the impacts of natural gas supply cost on gas flow and infrastructure deployment in China2016Inngår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 162, s. 1385-1398Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The impacts of gas supply costs on interregional gas flow and gas infrastructure deployment in China are analyzed out to 2035 by using an optimization model in the present study. There two options for gas supply includes successive two-step procedures of imports or domestic productions and transportation by using infrastructures within China. Four possible supply cost scenarios are proposed considering the uncertainties of import price, domestic unconventional gas production cost and geopolitical turbulence in import source countries. The analysis results show that (1). Domestic unconventional gas production cost (wellhead price) and gas import cost (import gas price represented by CIF) are two key points to gas flow and infrastructure deployment in China; (2). The development of unconventional gas is conductive to supply cost reduction and maintenance of infrastructure deployment stability, especially to Southwest and North China regions; (3). When gas import price increases, LNG import will decrease more than pipeline import, and imported LNG will be partly replaced by pipeline import rather than domestic gas in coastal regions; (4). The disruption of gassupply from Myanmar will lead to great changes of gas flow and infrastructure deployment in Southwest China regions; (5). The infrastructures are deployed according to the optimization gas flow in different scenarios.

  • 207.
    Zhang, X.
    et al.
    ABB AB, Corporate Research, Vasteras, Sweden.
    Yan, J.
    Vattenfall AB, Stockholm, Sweden.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Chekani, S.
    Royal Institute of Technology, Stockholm, Sweden .
    Liu, L.
    Royal Institute of Technology, Stockholm, Sweden .
    Energy saving for biogas production and upgrading - Thermal integration2014Inngår i: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 61, s. 121-125Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Thermal integration of anaerobic digestion (AD) biogas production with amine based biogas upgrading has been studied for improving the overall thermal efficiencies of the two systems. The thermal characteristics have been investigated for typical AD raw biogas generation and MEA absorption biogas upgrading. The investigation provides a basic understanding of energy saving for both industrial scale biogas production and upgrading processes. The thermal integration is carried out based on the thermal characteristics of the two systems by well-defined case studies, which take the following factors into account such as important thermal conditions of sub-systems, material and energy balances, the efficiencies of heat exchange and heat transfer, necessary integration optimization and ambient conditions. The results show that the thermal integration is achievable with very positive effects for overall energy efficiency and water usage.

  • 208.
    Zhang, Xiaojing
    et al.
    ABB AB, Corp Res, Västerås, Sweden.
    Yan, Jinying
    Vattenfall AB, Stockholm, Sweden.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Chekani, Shabnam
    Royal Inst Technol,Stockholm, Sweden.
    Liu, Loncheng
    Royal Inst Technol,Stockholm, Sweden.
    Investigation of thermal integration between biogas production and upgrading2015Inngår i: Energy Conversion and Management, ISSN 0196-8904, E-ISSN 1879-2227, Vol. 102, s. 131-139Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Thermal integration of anaerobic digestion (AD) biogas production with amine-based chemical absorption biogas upgrading has been studied to improve the overall efficiency of the intergraded system. The thermal characteristics have been investigated for industrial AD raw biogas production and amine-based chemical absorption biogas upgrading. The investigation provides a basic understanding for the possibilities of energy saving through thermal integration. The thermal integration is carried out through well-defined cases based on the thermal characteristics of the biogas production and the biogas upgrading. The following factors are taken into account in the case study: thermal conditions of sub-systems, material and energy balances, cost issues and main benefits. The potential of heat recovery has been evaluated to utilise the waste heat from amine-based upgrading process for the use in the AD biogas production. The results show that the thermal integration has positive effects on improving the overall energy efficiency of the integrated biogas plant. Cost analysis shows that the thermal integration is economically feasible. 

  • 209.
    Zhao, R.
    et al.
    Ministry of Education of China, Tianjin, China.
    Deng, S.
    Ministry of Education of China, Tianjin, China.
    Wang, S.
    Tianjin University, Tianjin, China.
    Zhao, L.
    Ministry of Education of China, Tianjin, China.
    Zhang, Y.
    Ministry of Education of China, Tianjin, China.
    Liu, B.
    Ministry of Education of China, Tianjin, China.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Yu, Z.
    University of Stavanger, Stavanger, Norway.
    Thermodynamic research of adsorbent materials on energy efficiency of vacuum-pressure swing adsorption cycle for CO2 capture2018Inngår i: Applied Thermal Engineering, ISSN 1359-4311, E-ISSN 1873-5606, Vol. 128, s. 818-829Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper presents a comprehensive thermodynamic research on energy efficiency of vacuum-pressure swing adsorption (VPSA). The study examined the influence from four types of typical adsorbent materials on the energy efficiency of VPSA by cycle parameters. The selected adsorbent materials are activated carbons, zeolite 5A, zeolite 13X, silica gels, and metal-organic frameworks (MOFs). The study also analyzes the effects of separation temperature, adsorption pressure, desorption pressure, CO2 concentration and percent of unused bed on the energy-efficiency of VPSA cycle. The examined performance parameters are CO2 working capacity, proportionality factor, energy consumption and second-law efficiency. The results show that the energy consumption is approximately 2.0–4.5 MJ/kg and the second-law efficiencies are 4–7% for VPSA cycles using the five adsorbent materials. The effect of adsorbent materials on the energy efficiency mainly depends on the proportionality factor of CO2 working capacity (β) of VPSA cycle, which is important to screen materials at the fixed cyclic boundary conditions and preliminary calculation of second-law efficiency for VPSA cycles. For existing adsorbent materials which are Type I commonly, the lower values of β would lead to the higher second-law efficiencies. The development of new adsorbents of Type III would be extremely urgent in near future. 

  • 210.
    Zhao, R.
    et al.
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Liu, L.
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Zhao, L.
    Ministry of Education of China, Tianjin, China.
    Deng, S.
    Ministry of Education of China, Tianjin, China.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Thermodynamic analysis on carbon dioxide capture by Electric Swing Adsorption (ESA) technology2018Inngår i: Journal of CO2 Utilization, ISSN 2212-9820, E-ISSN 2212-9839, Vol. 26, s. 388-396Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This study explores the impacts of materials, such as adsorbents and electrodes, on the energy efficiency of a 4-step ESA cycle for CO2 capture. Three types of adsorbents including activated carbon honeycomb monolith (ACHM) and two hybrid adsorbents are compared, and two kinds of electrodes such as aluminum and brass are combined for comparative analysis. Process description of ESA cycle, including feed, electrification, electrification with purge and cooling, is presented via the adsorption isotherm diagram. By the theory of thermodynamic carbon pump, sensitivity analysis of cycle parameters is evaluated in terms of the second-law efficiency (Eff2nd) and the electrical heating efficiency (Effele). The results show that Eff2nd of the employed adsorbents is in the range of 1.17%-6.15%, and Effele of the selected electrodes is between 27.46% and 60.91%. Among the three adsorbents, Eff2nd of ACHM is the lowest one compared to the others. Similarly, Effele of the combination with brass is superior to that of the groups with aluminum. However, the actual efficiency of ESA cycle is the production of both Eff2nd and Effele, which is approximately 1.03%-3.66%. Typical measures are proposed to reduce the heat loss of the adsorbents and electrodes as well for future work. 

  • 211.
    Zhao, R.
    et al.
    Royal Institute of Technology, Sweden.
    Liu, L.
    Royal Institute of Technology, Sweden.
    Zhao, L.
    Tianjin University, Ministry of Education, China.
    Deng, S.
    Tianjin University, Ministry of Education, China.
    Li, S.
    Tianjin University, Ministry of Education, China.
    Zhang, Y.
    Tianjin University, Ministry of Education, China.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Techno-economic analysis of carbon capture from a coal-fired power plant integrating solar-assisted pressure-temperature swing adsorption (PTSA)2019Inngår i: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 214, s. 440-451Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper presents a techno-economic study to seek the feasibility about the proposed system that integrating solar-assisted pressure-temperature swing adsorption (PTSA) into an 800MWe coal-fired power plant. Solar energy has the potential to supply thermal energy demand for carbon capture, which can avoid the energy consumption of the traditional method such as the steam extraction. The performance of the proposed system is largely affected by the climatic conditions and solar collector's types. The assessment criteria include carbon emission intensity (CEI), levelized cost of electricity (LCOE) and cost of CO2 avoidance (COA). By the parametric analysis, the results show that CEI of the novel system with solar thermal collectors is approximately 2g/kWh lower than that of the referenced power plant with CO2 adsorption capture. In addition, CEI of the novel system can be further decrease with the decline of desorption temperature, adsorption pressure and desorption pressure. For the sake of lower LCOE and COA, the prices of the power plant capacity, adsorbents and solar collectors should be reduced. Specifically, LCOE of the system with evacuated tube collector will be lower than that of the reference system with CO2 capture as the price of solar field is lower than 46.08 USD/m2.

  • 212.
    Zhao, R.
    et al.
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Liu, L.
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Zhao, L.
    Ministry of Education of China, Tianjin, China.
    Deng, S.
    Ministry of Education of China, Tianjin, China.
    Li, S.
    Ministry of Education of China, Tianjin, China.
    Zhang, Y.
    Ministry of Education of China, Tianjin, China.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Thermodynamic exploration of temperature vacuum swing adsorption for direct air capture of carbon dioxide in buildings2019Inngår i: Energy Conversion and Management, ISSN 0196-8904, E-ISSN 1879-2227, Vol. 183, s. 418-426Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Abrupt climate change such as the loss of Arctic sea-ice area urgently needs negative emissions technologies. The potential application of direct air capture of carbon dioxide from indoor air and outdoor air in closed buildings or crowded places has been discussed in this paper. From the aspects of carbon reduction and indoor comfort, the ventilation system integrating a capture device is of great value in practical use. For ultra-dilute carbon dioxide sources, many traditional separation processes have no cost advantages, but adsorption technologies such as temperature vacuum swing adsorption is one of suitable methods. Thermodynamic exploration has been investigated regarding minimum separation work and second-law efficiency at various concentrations in the air. The influence of concentration, adsorption temperature, desorption temperature and desorption pressure on the energy efficiency has also been evaluated. Results show that the minimum separation work for the level of 400 ppm is approximately 20 kJ/mol. The optimal second-law efficiencies are 44.57%, 37.55% and 31.60%, respectively for 3000 ppm, 2000 ppm and 1000 ppm. It means that a high energy-efficiency capture device in buildings merits attention in the exploration of the possibility of approaching negative carbon buildings. 

  • 213.
    Zhao, R.
    et al.
    Ministry of Education of China, Tianjin, China.
    Zhao, L.
    Ministry of Education of China, Tianjin, China.
    Wang, S.
    Tianjin University, Tianjin, China.
    Deng, S.
    Ministry of Education of China, Tianjin, China.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Yu, Z.
    University of Stavanger, Stavanger, Norway.
    Solar-assisted pressure-temperature swing adsorption for CO2 capture: Effect of adsorbent materials2018Inngår i: Solar Energy Materials and Solar Cells, ISSN 0927-0248, E-ISSN 1879-3398, Vol. 185, s. 494-504Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Because of the ability to utilize the low-grade solar thermal energy for regeneration, a CO2 capture system characterized by solar-assisted pressure temperature swing adsorption (SOL-PTSA) is studied on the effects of adsorbent materials. A detailed cycle description is firstly presented within the diagram of adsorption isotherm for the energy-efficiency analysis. Typical adsorbent materials, including zeolites and chemical adsorbent, are assessed in terms of sensible heat and latent heat, etc. Then, the energy consumption and the second-law efficiency, which can be considered as lumped indicators from such material parameters, are chosen as performance indicators as well. The influence of separation temperature, desorption temperature, CO2 concentration and CO2 adsorption pressure on system performance are finally obtained. For the chosen three adsorbent materials, the energy consumption of SOL-PTSA system is at the range of 25.96–87.76 kJ/mol, and the corresponding second-law efficiencies are at the range of 9.18–26.89%. The effect of adsorbent materials on the energy-efficiency of SOL-PTSA system mainly depends on specific heat, CO2 working capacity and cycle design. In addition, the integration options of solar energy into PTSA technology are also discussed from the standpoint of the utilization of solar grade heat due to two energy loads required for PTSA's operation.

  • 214.
    Zhu, K.
    et al.
    Tianjin University of Commerce, China.
    Cui, Z.
    Tianjin University of Commerce, China.
    Wang, Y.
    Tianjin University of Commerce, China.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Tianjin University of Commerce, China.
    Zhang, X.
    ABB Corporate Research, Sweden.
    Franke, C.
    Estimating the maximum energy-saving potential based on IT load and IT load shifting2017Inngår i: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 138, s. 902-909Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Cooling system consumes more than 35% of total electricity in most data centers. The provided cooling normally exceeds the actual demand of IT equipment in order to assure the safe operation, resulting in a low energy efficiency. In this paper, a novel method based on demand response was proposed to precisely control the cooling supply, and the energy saving potential was assessed systematically. Compared to the reference case, in which the cooling demand is determined by assuming all of servers are in the running status, when the cooling demand was determined based on the measured dynamic IT load at room level, row level, rack level and server level, it can be reduced by 7.9%, 14.2%, 15.6% and 17.9% respectively for the random selected 48 h. In addition, IT load shifting also has a big potential to save energy, as it can make the cooling system working at a higher energy efficiency, which varies with loads. Two cases were studied: even distribution of IT load and optimized IT load shifting. Compared to the best case that determines the cooling demand according to the IT load at server level, they can further reduce the electricity consumption of cooling systems by 0.9%, and 1.2%. 

  • 215.
    Zhu, K.
    et al.
    Tianjin Key Laboratory of Refrigeration technology, Tianjin University of Commerce, Tianjin 300134, China.
    Li, X.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Tianjin Key Laboratory of Refrigeration technology, Tianjin University of Commerce, Tianjin 300134, China.
    Chen, X.
    Tianjin Key Laboratory of Refrigeration technology, Tianjin University of Commerce, Tianjin 300134, China.
    Wang, Y.
    Tianjin Key Laboratory of Refrigeration technology, Tianjin University of Commerce, Tianjin 300134, China.
    Optimization of a loop heat pipe (LHP) with wick separated from heating surface2019Inngår i: Energy Procedia, Elsevier Ltd , 2019, Vol. 158, s. 2409-2416Konferansepaper (Fagfellevurdert)
    Abstract [en]

    A novel LHP, in which the wick is separated from the heating surface, has been proposed. And then, a steam chamber is formed, which can effectively use the pressure head of evaporation. This work is to optimize the key parameters in order to further improve the performance of such a novel LHP. A mathematical model, based on the node analysis method, had been established, which was validated against the experimental data. The height of steam chamber, the type of working fluids, and the material of wick were identified as key parameters to be optimized. The heating surface temperature, which was the highest temperature, and the start-up time were selected as the key performance indicators. Results showed there existed an optimal height of steam chamber (3mm) and charging ratio (55%) to achieve the lowest heating surface temperature and the shortest start-up time. For different working fluids, ammonia showed the best performance, followed by acetone, ethanol, and water. And the ceramic wick, with low thermal conductivity, demonstrated a better performance than the steel-nickel wick and copper wick with high thermal conductivity.

  • 216.
    Zhu, K.
    et al.
    Tianjin Key Laboratory of Refrigeration technology, Tianjin University of Commerce, Tianjin 300134, China.
    Li, X.
    Tianjin Key Laboratory of Refrigeration technology, Tianjin University of Commerce, Tianjin 300134, China.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Tianjin Key Laboratory of Refrigeration technology, Tianjin University of Commerce, Tianjin 300134, China.
    Yang, Z.
    Tianjin Key Laboratory of Refrigeration technology, Tianjin University of Commerce, Tianjin 300134, China.
    Wang, Y.
    Tianjin Key Laboratory of Refrigeration technology, Tianjin University of Commerce, Tianjin 300134, China.
    Experimental investigation on the effect of heat sink temperature on operational characteristics of a new-type loop heat pipe2019Inngår i: Energy Procedia, Elsevier Ltd , 2019, Vol. 158, s. 2423-2429Konferansepaper (Fagfellevurdert)
    Abstract [en]

    With the development of the miniaturization and the high integration of electronic chip, the thermal management of the high power electronic becomes a major challenge. In this paper the influence of heat sink temperature on operational characteristics was comprehensively conducted and the 35% of charging ratio was selected through the experiment study. To evaluate the LHP system, temperatures, start-up time, thermal resistance, and evaporator heat transfer coefficient were selected as performance indicators. The result showed that, there existed an optimal heat sink temperature (18 o C) to obtain the lowest evaporator bottom temperature (77 o C), the shortest start-up time (1000s), the smallest thermal resistance (0.29k/W), and the highest evaporator heat transfer coefficient (3.110 4 W/(m 2 ·k)). The temperature range to keep a high performance of LHP system was 14-20 o C. The conclusion obtained through the experiment can provide the reference of design the cooling system when the LHP system applied into the electric cooling.

  • 217.
    Zhu, K.
    et al.
    Tianjin University of Commerce, Tianjin, China.
    Li, X.
    Tianjin University of Commerce, Tianjin, China.
    Wang, Y.
    Tianjin University of Commerce, Tianjin, China.
    Chen, X.
    Tianjin University of Commerce, Tianjin, China.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Dynamic performance of loop heat pipes for cooling of electronics2017Inngår i: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 142, s. 4163-4168Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    With the performance improvement of electronics, the recent trends in electronic industry pose a big challenge on heat dissipation. Conventional methods, i.e. air cooling, may not be able to handle the fast increasing heat flux. Using heat pipes, which have numerous advantages such as high heat transfer coefficient, non-movable components, longer transport distance, and compact structures, emerges to be one competitive option for electronics cooling. Based on the node analysis method and the conservation of energy and mass, this work develops a mathematic model to simulate the operation of heat pipes. After it is validated against experimental data, it is further applied to evaluate the dynamic performance of using a heat pipe for electronics cooling. Results show that the operation temperature of evaporator ranges from 47.5°C to73.1°C, which implies that the heat pipe can effectively cool down the CPU at different running status. The charging ratio of working fluid is identified as a key parameter and exists an optimal value. When keeping the charging ratio constant, a larger evaporator area can achieve a lower operating temperature. 

  • 218.
    Zhu, K.
    et al.
    Tianjin Key Laboratory of Refrigeration Technology, Tianjin University of Commerce, Tianjin, China.
    Li, Xueqiang
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. School of Environmental Science and Engineering, Tianjin University, Tianjin, China.
    Campana, Pietro Elia
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. School of Chemical Science & Engineering, KTH Royal Institute of Technology, Stockholm, Sweden.
    Techno-economic feasibility of integrating energy storage systems in refrigerated warehouses2018Inngår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 216, s. 348-357Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This work evaluates the techno-economic feasibility of integrating the cold energy storage system and the electrical energy storage system in a refrigerated warehouse for shifting the power consumption. A dynamic model has been developed in TRNSYS®. Based on the dynamic simulation, the performance and benefit of those two types of energy storage systems were compared. Results showed that, the integration of a cold energy storage can reduce the electricity consumption and operational cost by 4.3% and 20.5%, respectively. Even though integrating a battery system will increase the electricity consumption by 3.9%, it can reduce the operational cost by 18.7%. The capacity of the energy storage systems, the battery price and the peak electricity price had been identified as key parameters affecting the performance and benefit. To achieve a payback period less than 3 year, for the integration of a cold energy storage system, the peak electricity price should be increased by 25% from the current level, while for the integration of a battery system, the battery price should drop to 0.7 kRMB/kWh.

  • 219.
    Zhu, K.
    et al.
    Key Laboratory of Refrigeration Technology of Tianjin, Tianjin University of Commerce, Tianjin, China.
    Li, Xueqiang
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Key Laboratory of Refrigeration Technology of Tianjin, Tianjin University of Commerce, Tianjin, China.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Key Laboratory of Refrigeration Technology of Tianjin, Tianjin University of Commerce, Tianjin, China.
    Chen, X.
    Key Laboratory of Refrigeration Technology of Tianjin, Tianjin University of Commerce, Tianjin, China.
    Wang, Y.
    Key Laboratory of Refrigeration Technology of Tianjin, Tianjin University of Commerce, Tianjin, China.
    Experimental and theoretical study of a novel loop heat pipe2018Inngår i: Applied Thermal Engineering, ISSN 1359-4311, E-ISSN 1873-5606, Vol. 130, s. 354-362Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In order to reduce the heat leakage from the evaporator and achieve a longer transport distance, a new type of loop heat pipe (LHP) has been proposed based on a hypothesis that the circulation of working fluids is driven by not only the capillary head, but also the pressure head due to evaporation. In the evaporator, the wick is separated from the heating surface by a chamber, which can effectively use the pressure head generated by evaporation. In this work, a prototype of such a LHP was studied experimentally and theoretically. In order to understand the mechanism of operation, a new mathematical model was established. Comparing the simulated results with the experimental data about the operation temperature, a good agreement was observed that the average absolute deviation and the maximum absolute deviation were in ranges of 0.67–1.21 °C and −1.3 to 6 °C, respectively. With the validated model, the two driving forces were investigated. Results showed that the ratio of the pressure head of evaporation to the capillary head was in a range of 59–54% corresponding to heating powers from 30 W to 110 W. It confirms that the pressure head due to evaporation plays an important role in the circulation of working fluids.

  • 220.
    Zhu, Kai
    et al.
    Tianjin University of Commerce, Tianjin, China .
    Chen, Xiaoqing
    Tianjin University of Commerce, Tianjin, China .
    Dai, Baomin
    Tianjin University of Commerce, Tianjin, China .
    Zheng, Mingzhu
    Tianjin University of Commerce, Tianjin, China .
    Wang, Yabo
    Tianjin University of Commerce, Tianjin, China .
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Tianjin University of Commerce, Tianjin, China .
    Operation characteristics of a new-type loop heat pipe (LHP) with wick separated from heating surface in the evaporator2017Inngår i: Applied Thermal Engineering, ISSN 1359-4311, E-ISSN 1873-5606, Vol. 123, s. 1034-1041Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The loop heat pipe (LHP) has been widely used for cooling devices with high heat flux. In addition to the capillary pumping force, the pressure head due to evaporation has been assumed to play an important role in the circulation of working fluid. Based on such a hypothesis, a new LHP is designed, in which the wick is separated from the heating surface in the evaporator. Experiments show that such a LHP can start up successfully and reach steady operation, which indirectly verified the hypothesis. The influences of heating power, height of steam chamber, pore radius and porosity of wick are comprehensively investigated. The results show that the start-up time of the new-designed LHP is shorter and the temperature fluctuation is smaller at higher heating power. The steam chamber height has clear impacts on the start-up time and the thermal resistance. The start-up time with the steam chamber height of 2 mm is shorter than that of 3 mm, but the thermal resistance is relatively higher. Moreover, a larger pore radius and a higher porosity of the wick can lead to a shorter start-up time and a smaller thermal resistance of the new LHP.

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