PubAg

Main content area

You searched for: Subject "heat" Remove constraint Subject: "heat"
Start Over

Search

79,231  Search Results

« Previous | 1 - 20 of 79,231 |
Number of results to display per page

Search Results

1. Effects of tube shapes on the performance of recuperative and regenerative heat exchangers

Author:
Tran, Ngoctan; Wang, Chi-Chuan
Source:
Energy 2019 v.169 pp. 1-17
ISSN:
0360-5442
Subject:
heat exchangers; heat transfer,   etc   ; prediction;     Show all 3 Subject
Abstract:
... In the present work, the effects of tube shapes on the heat transfer and fluid flow characteristics of the shell-and-tube heat exchangers –including square, rectangular, circular, elliptical, equilateral- and isosceles-triangular shapes –are numerically investigated in detail. Six parameters –including (1) rectangular-tube ratios (⍺ = tube height/width), (2) triangular-tube ratios (β = two-side ed ...
DOI:
10.1016/j.energy.2018.11.127

2. Hourly 50-year simulations of ground-coupled heat pumps using high-resolution analytical models

Author:
Li, Min; Zhou, Cheng; Rao, Zhenghua
Source:
Energy conversion and management 2019 v.193 pp. 15-24
ISSN:
0196-8904
Subject:
heat exchangers; heat pumps; heat transfer,   etc   ; algorithms; equations; models; temperature;     Show all 7 Subjects
Abstract:
... This paper reports on an algorithm for hourly simulation of ground-coupled heat pump (GCHP) systems. This algorithm integrates the newest analytical models for COP of heat pumps and for heat transfer of ground heat exchangers (GHEs). These analytical models make the algorithm computationally fast and efficient. The algorithm comprises 7 independent equations for solving 7 system variables, thus in ...
DOI:
10.1016/j.enconman.2019.04.051

3. Effects of arrangement geometry and number of boreholes on thermal interaction coefficient of multi-borehole heat exchangers

Author:
Gultekin, Ahmet; Aydin, Murat; Sisman, Altug
Source:
Applied energy 2019 v.237 pp. 163-170
ISSN:
0306-2619
Subject:
heat exchangers; heat pumps; heat transfer,   etc   ; energy efficiency; geometry;     Show all 5 Subjects
Abstract:
... In large-scale ground-source heat pump applications, a large number of borehole heat exchangers are used and performance losses become an important issue due to thermal interactions. Dependency of total performance losses on borehole spacing can analytically be expressed by using thermal interaction coefficient. For a given application field, interaction coefficient depends on number of boreholes ...
DOI:
10.1016/j.apenergy.2019.01.027

4. Thermal-hydraulic characteristics of supercritical pressure CO2 in vertical tubes under cooling and heating conditions

Author:
Guo, Jiangfeng; Xiang, Mengru; Zhang, Haiyan; Huai, Xiulan; Cheng, Keyong; Cui, Xinying
Source:
Energy 2019 v.170 pp. 1067-1081
ISSN:
0360-5442
Subject:
heat exchangers; heat transfer; heat transfer coefficient,   etc   ; carbon dioxide; models;     Show all 5 Subjects
Abstract:
... The thermal-hydraulic properties of supercritical pressure CO2 (SCO2) in vertical tubes under cooling and heating conditions were numerically investigated by using SST turbulent model with variable turbulent Prandtl number model. Under cooling condition, the peak of heat transfer coefficient appears near the pseudo-critical point, the buoyancy effect enhances local heat transfer for upward flow wh ...
DOI:
10.1016/j.energy.2018.12.177

5. A theoretical study on a novel combined organic Rankine cycle and ejector heat pump

Author:
Zhang, Chenghu; Lin, Jiyou; Tan, Yufei
Source:
Energy 2019 v.176 pp. 81-90
ISSN:
0360-5442
Subject:
heat pumps; heat recovery,   etc   ; mixing; statistical models;     Show all 4 Subjects
Abstract:
... A novel combined organic Rankine cycle and ejector heat pump is proposed, which combines the organic Rankine cycle and ejector heat pump, and could produce both power output and heat output simultaneously. An ejector is installed on the turbine inlet side to increase the total heat exchange amount of the combined cycle by utilizing the injection capability of the high-pressure primary fluid. Using ...
DOI:
10.1016/j.energy.2019.03.190

6. Which dimensional model for the analysis of a coated tube adsorber for adsorption heat pumps?

Author:
Dias, João M.S.; Costa, Vítor A.F.
Source:
Energy 2019 v.174 pp. 1110-1120
ISSN:
0360-5442
Subject:
heat pumps; heat transfer,   etc   ; adsorption; models;     Show all 4 Subjects
Abstract:
... This paper presents the analysis of a coated tube adsorber for adsorption heat pumps (AHP), starting from a well-established physical model and providing information on how many dimensions need to be considered for a given accuracy. A lumped-parameter model, one-dimensional (radial direction) and two-dimensional (radial and longitudinal directions) distributed-parameter models describing the adsor ...
DOI:
10.1016/j.energy.2019.03.028

7. Development and eastward movement mechanisms of the Tibetan Plateau vortices moving off the Tibetan Plateau

Author:
Li, Lun; Zhang, Renhe; Wen, Min; Duan, Jianping
Source:
Climate dynamics 2019 v.52 no.7-8 pp. 4849-4859
ISSN:
0930-7575
Subject:
heat; latent heat,   etc   ; climate; equations; prediction; China;     Show all 6 Subjects
Abstract:
... Based on the Final operational global analysis data from the Global Forecasting System of the National Centers for Environment Prediction and the radiosonde data, the development and eastward movement mechanisms of 15 Tibetan Plateau vortices (TPVs) after they move off the plateau are investigated. The results show that the convergence to the east of the TPVs at 500 hPa, the divergence associated ...
DOI:
10.1007/s00382-018-4420-z

8. Design of heat integrated water networks with multiple contaminants

Author:
Zhao, Hui-Peng; Yang, Yang; Liu, Zhi-Yong
Source:
Journal of cleaner production 2019 v.211 pp. 530-536
ISSN:
0959-6526
Subject:
heat; heat exchangers,   etc   ; cost analysis; equipment design;     Show all 4 Subjects
Abstract:
... The heat integrated water networks have the features of complex network structure and high costs. To overcome the problems, this paper presents a new design method for heat integrated water networks with simple structure and low costs. The proposed method includes two steps: the water-using network is designed first by considering the concentration specifications of water-using processes, which is ...
DOI:
10.1016/j.jclepro.2018.11.210

9. Thermal-hydraulic performance of printed circuit heat exchanger with supercritical carbon dioxide airfoil fin passage and molten salt straight passage

Author:
Fu, Qianmei; Ding, Jing; Lao, Jiewei; Wang, Weilong; Lu, Jianfeng
Source:
Applied energy 2019 v.247 pp. 594-604
ISSN:
0306-2619
Subject:
heat exchangers; heat flow; heat transfer,   etc   ; carbon dioxide; flow resistance; heat transfer coefficient; kinetic energy; temperature;     Show all 8 Subjects
Abstract:
... Molten salt and supercritical carbon dioxide (S-CO2) are promising heat transfer fluids, but heat exchanger between molten salt and S-CO2 is seldom reported. By comprehensively considering low heat transfer coefficient of S-CO2 and high pressure loss of molten salt, printed circuit heat exchanger (PCHE) with S-CO2 airfoil fin passage and molten salt straight passage is first proposed and simulated ...
DOI:
10.1016/j.apenergy.2019.04.049

10. Ageing (dis)gracefully: Enabling designers to understand material change

Author:
Lilley, D.; Bridgens, B.; Davies, A.; Holstov, A.
Source:
Journal of cleaner production 2019 v.220 pp. 417-430
ISSN:
0959-6526
Subject:
heat,   etc   ; aesthetics; air;     Show all 3 Subjects
Abstract:
... From the moment of purchase, pristine objects are subjected to an array of stimuli including wear, impact, heat, light, water and air which alter their tactile and aesthetic properties. Material change is often regarded as ‘damage’ or ‘degradation’ and contributes to premature obsolescence but has potential to be used as a tool to engender emotional engagement with an object and extend product lif ...
DOI:
10.1016/j.jclepro.2019.01.304

11. Urban heat island impacts on building energy consumption: A review of approaches and findings

Author:
Li, Xiaoma; Zhou, Yuyu; Yu, Sha; Jia, Gensuo; Li, Huidong; Li, Wenliang
Source:
Energy 2019 v.174 pp. 407-419
ISSN:
0360-5442
Subject:
heat island,   etc   ; energy; temperature;     Show all 3 Subjects
Abstract:
... Urban heat island (UHI) could have significant impacts on building energy consumption by increasing space cooling demand and decreasing space heating demand. However, the impacts of UHI on building energy consumption were understudied due to challenges associated with quantifying UHI-induced temperature change and evaluating building energy consumption. In this study, we reviewed existing literatu ...
DOI:
10.1016/j.energy.2019.02.183

12. Analysis strategy for multi-criteria optimization: Application to inter-seasonal solar heat storage for residential building needs

Author:
Launay, S.; Kadoch, B.; Le Métayer, O.; Parrado, C.
Source:
Energy 2019 v.171 pp. 419-434
ISSN:
0360-5442
Subject:
heat,   etc   ; energy; equations; models;     Show all 4 Subjects
Abstract:
... As energetic systems become more and more complex, it is necessary to develop strategies for analyzing the influence of the parameters as well as their couplings. This approach is even unavoidable when the optimization procedure is based on multi-criteria. In the present work, we propose an analysis strategy for multi-criteria optimization applied to inter-seasonal solar heat storage for residenti ...
DOI:
10.1016/j.energy.2018.12.181

13. Experimental study on the performance of a novel in–house heat pump water heater with freezing latent heat evaporator and assisted by domestic drain water

Author:
Guo, Xiaochao; Ma, Zhixian; Ma, Liangdong; Zhang, Jili
Source:
Applied energy 2019 v.235 pp. 442-450
ISSN:
0306-2619
Subject:
heat; heat pumps; heat transfer coefficient,   etc   ; drainage water; energy; freezing; latent heat; prototypes; temperature; wastewater;     Show all 10 Subjects
Abstract:
... The temperature of domestic drain water is relatively high, but its flux is sometimes insufficient as a heating source. Thus, the conventional wastewater source heat pump water heater is incapable of meeting user heating demand given the limited sensible heat temperature difference in many situations. To address this problem, a novel in–house heat pump water heater with a freezing latent heat evap ...
DOI:
10.1016/j.apenergy.2018.10.094

14. The effects of component dimensions on heat transfer and pressure loss in shell and tube heat exchangers

Author:
Kayabasi, Erhan; Alperen, Munip Alpaslan; Kurt, Hüseyin
Source:
International journal of green energy 2019 v.16 no.2 pp. 200-210
ISSN:
1543-5083
Subject:
heat exchangers; heat transfer; heat transfer coefficient,   etc   ; computer software; geometry; industrial applications; specific heat; temperature;     Show all 8 Subjects
Abstract:
... In this study, the effects of geometric properties such as baffle spacing, baffle cut, sealing strips, gaps between heat exchanger components, number of tubes and tube passes have been investigated for shell and tube heat exchangers (STHE). For this purpose, geometrical dimensions and data of a specific heat exchanger (HE) used in an industrial application have been obtained. The HTRI Xchanger Sui ...
DOI:
10.1080/15435075.2018.1555162

15. Theoretical and experimental research on the influence of initial temperature on the flammability of hydrocarbon-CO2 mixture using in organic Rankine cycle

Author:
Tian, Hua; Liu, Yuewei; Shu, Gequn; Li, Linqing; Huo, Xu
Source:
Energy 2019 v.167 pp. 939-949
ISSN:
0360-5442
Subject:
heat recovery,   etc   ; flammability; temperature;     Show all 3 Subjects
Abstract:
... As an effective waste heat recovery technique, the hydrocarbon-CO2 mixture based Rankine cycle is always operating on a specific temperature, which has a noticeable influence on flammability limits. Thus it is critical to research flammability limit of hydrocarbon-CO2 at various initial temperatures. Focusing on the hydrocarbon-CO2 mixture, this paper first measured its flammability limits at diff ...
DOI:
10.1016/j.energy.2018.10.136

16. Design space exploration for waste heat recovery system in automotive application under driving cycle

Author:
Zhao, Mingru; Canova, Marcello; Tian, Hua; Shu, Gequn
Source:
Energy 2019 v.176 pp. 980-990
ISSN:
0360-5442
Subject:
heat exchangers; waste heat recovery,   etc   ; algorithms; guidelines; models;     Show all 5 Subjects
Abstract:
... Organic Rankine Cycle (ORC) systems have been recently considered for the promising application to Waste Heat Recovery (WHR) in automotive application. However, the design of ORC systems for highly transient operations typical of heavy-duty vehicles faces several challenges. This work extends the method of Design Space Exploration (DSE) to optimize the design of an ORC system for heavy-duty vehicl ...
DOI:
10.1016/j.energy.2019.04.063

17. Effect of different flow schemes on heat recovery from Enhanced Geothermal Systems (EGS)

Author:
Asai, Pranay; Panja, Palash; McLennan, John; Deo, Milind
Source:
Energy 2019 v.175 pp. 667-676
ISSN:
0360-5442
Subject:
heat production; heat recovery,   etc   ; geothermal energy; models; temperature; Utah;     Show all 6 Subjects
Abstract:
... Operational optimization is the key to maximize the heat extraction efficiency of Enhanced Geothermal Systems (EGS). Injection/production flowrate is one of the operational parameters that can be easily manipulated to produce desired amount of energy. In this study, the effect of different flow schemes on the rate of heat production is analyzed over a period of 30 years. Seven flow schemes (four c ...
DOI:
10.1016/j.energy.2019.03.124

18. A flexible and multi-functional organic Rankine cycle system: Preliminary experimental study and advanced exergy analysis

Author:
Chen, Jianyong; Zheng, Xiaosheng; Guo, Guiqi; Luo, Xianglong; Chen, Ying; Yang, Zhi
Source:
Energy conversion and management 2019 v.187 pp. 339-355
ISSN:
0196-8904
Subject:
heat exchangers; heat transfer,   etc   ; electric energy consumption; exergy; temperature;     Show all 5 Subjects
Abstract:
... In the present study, a novel and flexible experimental facility of an organic Rankine cycle system is constructed. Four extra heat exchangers than traditional test bench are equipped for the system performance testing with different evaporator and condenser or heat transfer examinations of the evaporator and condenser. The combination of an expansion valve and a cooler is designed to simulate the ...
DOI:
10.1016/j.enconman.2019.03.050

19. Effect of fluid dryness and critical temperature on trans-critical organic Rankine cycle

Author:
Song, Chongzhi; Gu, Mingyan; Miao, Zheng; Liu, Chao; Xu, Jinliang
Source:
Energy 2019 v.174 pp. 97-109
ISSN:
0360-5442
Subject:
heat; specific heat,   etc   ; entropy; exergy; flammability; temperature; toxicity;     Show all 7 Subjects
Abstract:
... In this paper, the effect of fluid dryness (represented by ξ = ds/dT, where T is temperature, s is entropy) and critical temperature on the trans-critical ORC performance is investigated. The thermal efficiency of fifty-two working fluids is examined at four typical heat source temperatures. The results show that the critical temperature and fluid dryness have a significant impact on the system th ...
DOI:
10.1016/j.energy.2019.02.171

20. Measurement and calculation method of changing heat capacities during the reaction

Author:
Xu, Qiyue; Ding, Jiong; Yang, Suijun; Ye, Shuliang
Source:
Thermochimica acta 2019 v.675 pp. 55-62
ISSN:
0040-6031
Subject:
heat transfer; specific heat,   etc   ; energy; equations; models; reaction kinetics;     Show all 6 Subjects
Abstract:
... Schematic diagram of an asymmetric dual-channel system for measuring changing specific heat capacities during a reaction is introduced. After that a calculation and optimization procedure based on the energy equations and the two deviated reaction progresses from the asymmetric dual-channel system is presented. Using heat transfer model of the system, simulations of reactions with different heat c ...
DOI:
10.1016/j.tca.2019.03.004