Academic literature on the topic 'Working fluid temperature'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Working fluid temperature.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Journal articles on the topic "Working fluid temperature"

1

Zhu, Qidi, Zhiqiang Sun, and Jiemin Zhou. "Performance analysis of organic Rankine cycles using different working fluids." Thermal Science 19, no. 1 (2015): 179–91. http://dx.doi.org/10.2298/tsci120318014z.

Full text
Abstract:
Low-grade heat from renewable or waste energy sources can be effectively recovered to generate power by an organic Rankine cycle (ORC) in which the working fluid has an important impact on its performance. The thermodynamic processes of ORCs using different types of organic fluids were analyzed in this paper. The relationships between the ORC?s performance parameters (including evaporation pressure, condensing pressure, outlet temperature of hot fluid, net power, thermal efficiency, exergy efficiency, total cycle irreversible loss, and total heat-recovery efficiency) and the critical temperatures of organic fluids were established based on the property of the hot fluid through the evaporator in a specific working condition, and then were verified at varied evaporation temperatures and inlet temperatures of the hot fluid. Here we find that the performance parameters vary monotonically with the critical temperatures of organic fluids. The values of the performance parameters of the ORC using wet fluids are distributed more dispersedly with the critical temperatures, compared with those of using dry/isentropic fluids. The inlet temperature of the hot fluid affects the relative distribution of the exergy efficiency, whereas the evaporation temperature only has an impact on the performance parameters using wet fluid.
APA, Harvard, Vancouver, ISO, and other styles
2

Liu, Guanglin, Qingyang Wang, Jinliang Xu, and Zheng Miao. "Exergy Analysis of Two-Stage Organic Rankine Cycle Power Generation System." Entropy 23, no. 1 (December 30, 2020): 43. http://dx.doi.org/10.3390/e23010043.

Full text
Abstract:
Organic Rankine cycle (ORC) power generation is an effective way to convert medium and low temperature heat into high-grade electricity. In this paper, the subcritical saturated organic Rankine cycle system with a heat source temperature of 100~150 °C is studied with four different organic working fluids. The variations of the exergy efficiencies for the single-stage/two-stage systems, heaters, and condensers with the heat source temperature are analyzed. Based on the condition when the exergy efficiency is maximized for the two-stage system, the effects of the mass split ratio of the geothermal fluid flowing into the preheaters and the exergy efficiency of the heater are studied. The main conclusions include: The exergy efficiency of the two-stage system is affected by the evaporation temperatures of the organic working fluid in both the high temperature and low temperature cycles and has a maximum value. Under the same heat sink and heat source parameters, the exergy efficiency of the two-stage system is larger than that of the single-stage system. For example, when the heat source temperature is 130 °C, the exergy efficiency of the two-stage system is increased by 9.4% compared with the single-stage system. For the two-stage system, analysis of the four organic working fluids shows that R600a has the highest exergy efficiency, although R600a is only suitable for heat source temperature below 140 °C, while other working fluids can be used in systems with higher heat source temperatures. The mass split ratio of the fluid in the preheaters of the two-stage system depends on the working fluid and the heat source temperature. As the heat source temperature increases, the range of the split ratio becomes narrower, and the curves are in the shape of an isosceles triangle. Therefore, different working fluids are suitable for different heat source temperatures, and appropriate working fluid and split ratio should be determined based on the heat source parameters.
APA, Harvard, Vancouver, ISO, and other styles
3

Imre, Attila R., Réka Kustán, and Axel Groniewsky. "Thermodynamic Selection of the Optimal Working Fluid for Organic Rankine Cycles." Energies 12, no. 10 (May 27, 2019): 2028. http://dx.doi.org/10.3390/en12102028.

Full text
Abstract:
A novel method proposed to choose the optimal working fluid—solely from the point of view of expansion route—for a given heat source and heat sink (characterized by a maximum and minimum temperature). The basis of this method is the novel classification of working fluids using the sequences of their characteristic points on temperature-entropy space. The most suitable existing working fluid can be selected, where an ideal adiabatic (isentropic) expansion step between a given upper and lower temperature is possible in a way, that the initial and final states are both saturated vapour states and the ideal (isentropic) expansion line runs in the superheated (dry) vapour region all along the expansion. Problems related to the presence of droplets or superheated dry steam in the final expansion state can be avoided or minimized by using the working fluid chosen with this method. Results obtained with real materials are compared with those gained with model (van der Waals) fluids; based on the results obtained with model fluids, erroneous experimental data-sets can be pinpointed. Since most of the known working fluids have optimal expansion routes at low temperatures, presently the method is most suitable to choose working fluids for cryogenic cycles, applied for example for heat recovery during LNG-regasification. Some of the materials, however, can be applied in ranges located at relatively higher temperatures, therefore the method can also be applied in some limited manner for the utilization of other low temperature heat sources (like geothermal or waste heat) as well.
APA, Harvard, Vancouver, ISO, and other styles
4

Shuja, Shahzada Zaman, Bekir Sami Yilbas, and Hussain Al-Qahtani. "Thermal Assessment of Selective Solar Troughs." Energies 12, no. 16 (August 15, 2019): 3130. http://dx.doi.org/10.3390/en12163130.

Full text
Abstract:
A comparative study was carried out incorporating a novel approach for thermal performance evaluations of commonly used parabolic trough collectors, namely the Euro, Sky, and Helio troughs. In the analysis, pressurized water and therminol-VP1 (eutectic mixture of diphenyl oxide (DPO) and biphenyl) fluid were introduced as working fluids, and the governing equation of energy was simulated for various working fluid mass flow rates and inlet temperatures. The thermal performance of the troughs was assessed by incorporating the first- and second-law efficiencies and by using temperature increases and pressure drops of the working fluid. It was found that the first-law efficiency of the troughs increased with the working fluid mass flow rate, while it decreased with an increasing working fluid inlet temperature. The first-law efficiency remained the highest for the Euro trough, followed by the Sky and Helio troughs. The second-law efficiency reduced with an increasing working fluid mass flow rate, while it increased with an increasing working fluid inlet temperature. The second-law efficiency became the highest for the Helio Trough, followed by the Sky and Euro troughs. The temperature increase remained the highest along the length of the receiver for the Helio Trough compared to that corresponding to the Euro and Sky troughs for the same mass flow rate of the working fluid. The pressure drops in the working fluid became high for the Euro Trough, followed by the Sky and Helio troughs. The pressurized water resulted in higher second-law efficiency than the therminol-VP1 fluid did for all of the troughs considered.
APA, Harvard, Vancouver, ISO, and other styles
5

Kolasiński, Piotr. "The Method of the Working Fluid Selection for Organic Rankine Cycle (ORC) Systems Employing Volumetric Expanders." Energies 13, no. 3 (January 24, 2020): 573. http://dx.doi.org/10.3390/en13030573.

Full text
Abstract:
The working fluid selection is one of the most important issues faced when designing Organic Rankine Cycle (ORC) systems. The choice of working fluid is dictated by different criteria. The most important of them are safety of use, impact on the environment, and physical and chemical parameters. The type of ORC system in which the working fluid is to be used and the type of expander applied in this system is also affecting the working fluid selection. Nowadays, volumetric expanders are increasingly used in ORC systems. In the case of volumetric expanders, in addition to the aforementioned working fluid selection criteria, additional parameters are considered during the selecting of the working fluid, such as the range of operating pressures and geometric dimensions (determining the volume of working chambers) affecting the achieved power and efficiency of the expander. This article presents a method of selecting a working medium for ORC systems using volumetric expanders. This method is based on the dimensionless rating parameters applied for the comparative analysis of different working fluids. Dimensionless parameters were defined for selected thermal properties of the working fluids, namely thermal capacity, mean temperature of evaporation, mean temperature of condensation, pressure and volumetric expansion ratio, volumetric expandability, as well as the heat of preheating, vaporization, superheating, cooling, and liquefaction. Moreover, isentropic expansion work was considered as the rating parameter. In this article, in addition to the working fluid selection method, computational examples related to the selection of the working fluid for the ORC system fed by a heat source featuring specified temperatures are presented. The results of calculations of rating parameters and their comparison gave an outlook on the selection of appropriate working fluids.
APA, Harvard, Vancouver, ISO, and other styles
6

Vijayaraghavan, Sanjay, and D. Y. Goswami. "Organic Working Fluids for a Combined Power and Cooling Cycle." Journal of Energy Resources Technology 127, no. 2 (February 6, 2005): 125–30. http://dx.doi.org/10.1115/1.1885039.

Full text
Abstract:
A new thermodynamic cycle has been developed for the simultaneous production of power and cooling from low-temperature heat sources. The proposed cycle combines the Rankine and absorption refrigeration cycles, providing power and cooling as useful outputs. Initial studies were performed with an ammonia-water mixture as the working fluid in the cycle. This work extends the application of the cycle to working fluids consisting of organic fluid mixtures. Organic working fluids have been used successfully in geothermal power plants, as working fluids in Rankine cycles. An advantage of using organic working fluids is that the industry has experience with building turbines for these fluids. A commercially available optimization program has been used to maximize the thermodynamic performance of the cycle. The advantages and disadvantages of using organic fluid mixtures as opposed to an ammonia-water mixture are discussed. It is found that thermodynamic efficiencies achievable with organic fluid mixtures, under optimum conditions, are lower than those obtained with ammonia-water mixtures. Further, the refrigeration temperatures achievable using organic fluid mixtures are higher than those using ammonia-water mixtures.
APA, Harvard, Vancouver, ISO, and other styles
7

Zhang, Bing, Shuang Yang, Jin Liang Xu, and Guang Lin Liu. "Working Fluid Selection for Organic Rankine Cycles from a Molecular Structural Point of View." Advanced Materials Research 805-806 (September 2013): 649–53. http://dx.doi.org/10.4028/www.scientific.net/amr.805-806.649.

Full text
Abstract:
The optimum working conditions of 11 working fluids under different heat source temperatures for an organic Rankine cycle (ORC) were located in our previous work. In the current work, the system irreversibility of each candidate were calculated and compared at their optimal operating conditions. Obvious variation trends of both the cycle efficiency and irreversibility were found for different types of organic fluids. It is suggested, when selecting working fluid for our ORC system, the critical temperature should be as close as possible to the heat source temperature to achieve high cycle efficiency but avoid large irreversibility. The relationships between the structure of the molecules and the critical temperature of the working fluids are investigated qualitatively and potentially meaningful for the rational selection of proper organic fluids for certain ORCs.
APA, Harvard, Vancouver, ISO, and other styles
8

Mikielewicz, Dariusz, and Jarosław Mikielewicz. "Criteria for selection of working fluid in low-temperature ORC." Chemical and Process Engineering 37, no. 3 (September 1, 2016): 429–40. http://dx.doi.org/10.1515/cpe-2016-0035.

Full text
Abstract:
Abstract The economics of an ORC system is strictly linked to thermodynamic properties of the working fluid. A bad choice of working fluid could lead to a less efficient and expensive plant/generation unit. Some selection criteria have been put forward by various authors, incorporating thermodynamic properties, provided in literature but these do not have a general character. In the paper a simple analysis has been carried out which resulted in development of thermodynamic criteria for selection of an appropriate working fluid for subcritical and supercritical cycles. The postulated criteria are expressed in terms of non-dimensional numbers, which are characteristic for different fluids. The efficiency of the cycle is in a close relation to these numbers. The criteria are suitable for initial fluid selection. Such criteria should be used with other ones related to environmental impact, economy, system size, etc. Examples of such criteria have been also presented which may be helpful in rating of heat exchangers, which takes into account both heat transfer and flow resistance of the working fluid.
APA, Harvard, Vancouver, ISO, and other styles
9

Li, Jinwang, Ningxiang Lu, and Tianshu Cong. "Experimental study on evaporation-capillary pumping flow in capillary wick and working fluid system." Thermal Science, no. 00 (2019): 413. http://dx.doi.org/10.2298/tsci180918413l.

Full text
Abstract:
The evaporation-capillary pumping flow of the capillary wick and the working fluid system was experimentally studied in this paper. The capillary wick used in the experiment was fiber, and the working fluid contained water, ethanol and ethanol aqueous solution with water content of 25wt.%, 50wt.% and 75wt.%. The results show that the capillary pumping rate with ethanol as working fluid is between 210.0kg/m2sand 1812.5kg/m2swhen there is no heat load added. When the heating flux is 10616W/m2, 15924W/m2, 21231W/m2, 26539W/m2, the evaporation-capillary pumping rate is102.5kg/m2s, 247.5kg/m2s, 390.0kg/m2s and 530.0kg/m2s, respectively. The higher the heat load power, the greater the evaporation-capillary pumping rate and the higher the final stable temperature. With the increase of heat load power, the time required to reach temperature balance becomes shorter and the temperature fluctuations after reaching temperature equilibrium become larger. The obvious temperature fluctuation has occurred when the heat flux is 26539W/m2. The evaporation capillary pumping rate corresponding to the four different concentrations of ethanol solution in the experiment gradually decreases with the increase of water content. The temperature change processes and the final equilibrium temperatures of the four working fluids are nearly the same. The differences in boiling point of the working fluids do not have much influence here.
APA, Harvard, Vancouver, ISO, and other styles
10

Mustapic, Nenad, Vladislav Brkic, and Matija Kerin. "Subcritical organic ranking cycle based geothermal power plant thermodynamic and economic analysis." Thermal Science 22, no. 5 (2018): 2137–50. http://dx.doi.org/10.2298/tsci180104275m.

Full text
Abstract:
This paper is focused both on the thermodynamic and economic analysis of an organic Rankine cycle (ORC) based geothermal power plant. The analysis is applied to a case study of the geothermal field Recica near the city of Karlovac. Simple cycle configuration of the ORC was applied. Thermodynamic and economic performance of an ORC geothermal system using 8 working fluids: R134a, isobutane, R245fa, R601, R601a, R290, R1234yf, and R1234ze(E)], with different critical temperatures are analyzed. The thermodynamic analysis is performed on the basis of the analysis of influence of the operation conditions, such as evaporation and condensation temperatures and pressures, and evaporator and con-denser pinch point temperature difference, on the cycle characteristics such as net power output, and plant irreversibility. The economic analysis is performed on the basis of relationship between the net power output and the total cost of equipment used in the ORC. Mathematical models are defined for proposed organic Rankine geothermal power plant, and the analysis is performed by using the software package engineering equation solver. The analysis reveals that the working fluids, n-pentane and isopentane, show the best economic performances, regardless the evaporation temperatures, while the working fluid R1234yf and R290 have the best thermodynamic performances. In addition, each analyzed working fluid has its corresponding economically optimal condensation temperature (and condensation pressure). Economically optimal pinch point temperature difference of evaporator has different values, depending on the working fluid, while pinch point temperature difference of condenser has similar values for all analyzed working fluids. Analysis results demonstrate that the subcritical ORC geothermal power plant represents a promising option for electricity production application.
APA, Harvard, Vancouver, ISO, and other styles

Dissertations / Theses on the topic "Working fluid temperature"

1

Molyneaux, Glenn Arthur. "Resorption cycle heat pump with ammonia-water working fluid." Thesis, University of Ulster, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.326335.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Bai, Lijun. "Life Cycle Assessment of Electricity Generation from Low Temperature Waste Heat : The Influence of Working Fluid." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for energi- og prosessteknikk, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-19234.

Full text
Abstract:
In the metallurgical industry and in refineries and process industries, there is significant amount of waste heat, it is a challenged field to do the research for producing electricity from the energy of waste heat. Traditionallay, Organic Rankine Cycle(ORC)is used for generating electricity from low temperature heat source. Recently researchers are focusing on the supercritical Rankine cycle which uses CO2 as working fluid for which is more environmental friendly working fluid, possilbe reduced size and better utilization of lower temperature heat source.Currently this technology is under development and there is no manufacturing of this technology that can be observed. In this Master's thesis, the overall environmental impacts caused by the CO2 supercritical cycle will be evaluated:1. What are technologies available for producing electricity from low temperature heat?2. What is the electricity that can be generated from a given amount of heat and what type of equipment is needed for this?3. What are the environmental and resource impacts of this type of equipment, based on analyses of similar types of equipment?4. what is the environmental benefit from energy generation comparing with other fossil and renewable electricity production? 5. A brief economic analysis cosidering the waste heat electricity generation
APA, Harvard, Vancouver, ISO, and other styles
3

Mohamad, Salman. "EVALUATING THE ORGANIC RANKINE CYCLE (ORC) FOR HEAT TO POWER : Feasibility and parameter identification of the ORC cycle at different working fluid with district waste heat as a main source." Thesis, Mälardalens högskola, Framtidens energi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-38573.

Full text
Abstract:
New technologies to converting heat into usable energy are constantly being developed for renewable use. This means that more interactions between different energy grid will be applied, such as utilizing low thermal waste heat to convert its energy to electricity. With high electricity price, such technology is quite attractive at applications that develop low waste heat. In the case of excess heat in district heating (DH) grid and the electricity price are high, the waste heat can be converted to electricity, which can bring a huge profit for DH companies. Candidate technologies are many and the focus in this degree rapport is on the so-called Organic Rankine Cycle (ORC) that belongs to the steam Rankine cycle. Instead of using water as a working fluid, organic working fluid is being used because of its ability to boil at lower temperature. Because this technique is available, it also needs to be optimized, developed, etc. to achieve the highest appropriate efficiency. This can be done, for example, by modeling different layouts, analyzing functionality, performance and / or do a simulation of various suitable working fluids.  This is the purpose of this degree project and the research parts are to select working fluids suitable at low temperatures (70-120) °C, the difference analysis between the selected fluids and identification of the parameters that most affect the performance. There are many suitable methods to apply to achieve desired results. The method used in this rapport degree is commercial software such as Mini REFPROP, CoolPack, Excel but the most important part is simulation with AspenPlus. The selected and suitable working fluids between the chosen temperature interval are R236ea, R600, R245fa and n-hexane. Three common layouts were investigated, and they are The Basic ORC, ORC with an internal heat exchanger (IHE) and regenerative ORC. The results show that in comparison between 120°C and 70°C as a temperature source and without an internal heat exchanger (IHE), R600 at 70°C, has the highest efficiency about 13.55%. At 110°C n-hexane has the highest efficiency about 18.10%. R236ea has the lowest efficiency 13.16% at 70°C and 16.29% at 110°C. R236ea kept its low efficiency through all results. Without an IHE and a source range from 70 °C up to almost 90 °C, R600 has the highest efficiency and at 90°C n-hexane has the highest efficiency. With an IHE and between (70-90) °C R245fa still has the highest efficiency. With or without IHE and a heat source of 110 °C n-hexane has the highest efficiency 18.10% and 18.40%. R236ea gets the greatest increase 5.2% in efficiency but remains with the lowest efficiency. With Regenerative ORC, n-hexane had an optimal middle pressure about 0.76 bar. The optimal pressure corresponds to a thermal efficiency of 17.52%. The most important identified parameters are the fluid characteristics such as higher critical temperature, temperature source, heat sink, application placement and component performance.         The current simulations have been run at some fixed data input such as isentropic efficiencies, no pressure drops, adiabatic conditions etc. It was therefore expected that the same efficiency curve would repeat itself. This efficiency pattern would differ with less or higher values depending on the layout performance. However, this pattern was up to 90 degrees Celsius and gets a very noticeable change by the change of the efficiency for n-hexane. Therefore n-hexane is chosen with Regenerative ORC because it had the highest efficiency at the highest temperature source tested. This is due definitive to the fluid properties like its high critical temperature compared to the other selected fluids. R236ea remains the worst and that’s also related to the fluid properties. It is also important to note that these efficiencies are only from a thermodynamic perspective and may differ when combining both thermal and economic perspectives as well as application placement. These high efficiencies will certainly be lower at more advanced or real processes due to various factors that affect performance. Factors such as component´s efficiency and selection, pipe type and size, etc. To maintain a constant temperature when it’s not, flow regulation is then necessary and that’s also affects the performance.   The conclusion is that the basic ORC which does not have an IHE and from 70 up to 90 degrees Celsius, R600 has the highest efficiency. Higher temperature gives n-hexane the highest efficiency. With an IHE and between (70-90) °C R254fa has the highest efficiency. At higher temperature source n-hexane has the highest efficiency. ORC with an IHE has the best performance. The R236ea has the worst performance through all results. With regenerative ORC, an optimal meddle-pressure for n-hexane is 0.76 bar. Important parameters are The properties of the fluid, temperature source, heatsink, Application placement and component performance.
Nej
APA, Harvard, Vancouver, ISO, and other styles
4

Salami, Oyewole Taye [Verfasser], Johann Peter [Akademischer Betreuer] Plank, and Cordt [Akademischer Betreuer] Zollfrank. "Synthesis and Working Mechanism of Humic Acid Graft Copolymer Fluid Loss Additives Suitable for Cementing High Pressure/ High Temperature Oil and Gas Wells / Oyewole Taye Salami. Gutachter: Johann Peter Plank ; Cordt Zollfrank. Betreuer: Johann Peter Plank." München : Universitätsbibliothek der TU München, 2014. http://d-nb.info/1047883449/34.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Шевцов, Вадим Михайлович. "Вибір і обґрунтування температурних режимів роботи гідрооб'ємно-механічної трансмісії колісного трактора." Thesis, НТУ "ХПІ", 2018. http://repository.kpi.kharkov.ua/handle/KhPI-Press/38019.

Full text
Abstract:
Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.22.02 – автомобілі та трактори. – Національний технічний університет "Харківський політехнічний інститут", Харків, 2018 р. Дисертацію присвячено підвищенню ефективності використання тракторів з ГОМТ за рахунок визначення впливу температурних режимів роботи ГОП на показники роботи трансмісії, обґрунтуванню параметрів системи охолодження гідрооб'ємної передачі. Проведено аналіз щодо впливу температури робочої рідини на роботу гідросистеми та підходів щодо визначення температурних режимів роботи гідрооб'ємної передачі. Складена розширена матрична математична модель, яка відрізняється урахуванням, окрім кінематичних та силових, температурних режимів роботи ГОП в складі ГОМТ трактора та дозволяє визначити перепад температури робочої рідини на різних ланках гідросистеми в залежності від режимів роботи. Проведені експериментальні дослідження підтвердили адекватність складеної математичної моделі. Проаналізовано характер зміни температури робочої рідини в ГОП на робочих та транспортних передачах. Виявлено залежність загального ККД трансмісії на кожній передачі від температурних режимів роботи ГОП в її складі та сформовані рекомендації щодо методології вибору системи охолодження.
The thesis for granting the scientific degree of Candidate of technical sciences in the specialty 05.22.02 – cars and tractors. – National Technical University "Kharkiv Polytechnic Institute", Kharkiv, 2018. The thesis is devoted to increasing the efficiency of application the tractors based on hydrovolumetric mechanical transmissions (HVMT) through the determination of influence of temperature modes on hydrovolumetric transmission (HVT) characteristics justification of parameters of cooling system in HVT. The influence on temperature of working fluid on the work of hydro system has been carried out. There have been determined the approaches in the determination of temperature modes of HVT. The parameters of cooling system of HVT have been justified. There has been developed the extended mathematical model which considers the temperature, kinematics and power modes of volumetric hydraulic gear in HVMT of the wheel tractor. There also has been developed the mathematic model as a matrix that includes the description of kinematic parameters of HVMT, power parameters and energy conversion efficiency of all gearing parts and thermal characteristics. The provided research approved the adequacy of developed mathematical model. The variation of temperature of working fluid in the working and transport gear may be described as a curve with a maximum in a special zone. There has been determined the influence of temperature on general and volumetric energy conversion efficiency for the each gear and the recommendation for choosing the cooling system that consider the redistribution of power fluids in HVMT were performed.
APA, Harvard, Vancouver, ISO, and other styles
6

Шевцов, Вадим Михайлович. "Вибір і обґрунтування температурних режимів роботи гідрооб'ємно-механічної трансмісії колісного трактора." Thesis, НТУ "ХПІ", 2018. http://repository.kpi.kharkov.ua/handle/KhPI-Press/38015.

Full text
Abstract:
Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.22.02 – автомобілі та трактори. – Національний технічний університет "Харківський політехнічний інститут", Харків, 2018 р. Дисертацію присвячено підвищенню ефективності використання тракторів з ГОМТ за рахунок визначення впливу температурних режимів роботи ГОП на показники роботи трансмісії, обґрунтуванню параметрів системи охолодження гідрооб'ємної передачі. Проведено аналіз щодо впливу температури робочої рідини на роботу гідросистеми та підходів щодо визначення температурних режимів роботи гідрооб'ємної передачі. Складена розширена матрична математична модель, яка відрізняється урахуванням, окрім кінематичних та силових, температурних режимів роботи ГОП в складі ГОМТ трактора та дозволяє визначити перепад температури робочої рідини на різних ланках гідросистеми в залежності від режимів роботи. Проведені експериментальні дослідження підтвердили адекватність складеної математичної моделі. Проаналізовано характер зміни температури робочої рідини в ГОП на робочих та транспортних передачах. Виявлено залежність загального ККД трансмісії на кожній передачі від температурних режимів роботи ГОП в її складі та сформовані рекомендації щодо методології вибору системи охолодження.
The thesis for granting the scientific degree of Candidate of technical sciences in the specialty 05.22.02 – cars and tractors. – National Technical University "Kharkiv Polytechnic Institute", Kharkiv, 2018. The thesis is devoted to increasing the efficiency of application the tractors based on hydrovolumetric mechanical transmissions (HVMT) through the determination of influence of temperature modes on hydrovolumetric transmission (HVT) characteristics justification of parameters of cooling system in HVT. The influence on temperature of working fluid on the work of hydro system has been carried out. There have been determined the approaches in the determination of temperature modes of HVT. The parameters of cooling system of HVT have been justified. There has been developed the extended mathematical model which considers the temperature, kinematics and power modes of volumetric hydraulic gear in HVMT of the wheel tractor. There also has been developed the mathematic model as a matrix that includes the description of kinematic parameters of HVMT, power parameters and energy conversion efficiency of all gearing parts and thermal characteristics. The provided research approved the adequacy of developed mathematical model. The variation of temperature of working fluid in the working and transport gear may be described as a curve with a maximum in a special zone. There has been determined the influence of temperature on general and volumetric energy conversion efficiency for the each gear and the recommendation for choosing the cooling system that consider the redistribution of power fluids in HVMT were performed.
APA, Harvard, Vancouver, ISO, and other styles
7

Medaska, Michael Kenneth. "The measurement of temperatures and forces in a turning operation with cutting fluid." Thesis, Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/15983.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Brocheny, Pascal O. "Modeling of the transient behavior of heat pipes with room-temperature working fluids." Connect to this title online, 2006. http://etd.lib.clemson.edu/documents/1175184863/.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Chamoun, Marwan. "Modélisation, conception et étude expérimentale d’une pompe à chaleur industrielle à eau à haute température." Thesis, Lyon, INSA, 2012. http://www.theses.fr/2012ISAL0132/document.

Full text
Abstract:
Le contexte énergétique global impose, durablement aux industriels la poursuite des efforts en matière d’efficacité énergétique nécessitant le déploiement de nouveaux procédés innovants éco-efficaces. Une meilleure gestion de l’énergie permet l’amélioration de l’efficacité énergétique globale des procédés ainsi que la réduction des émissions de CO2. Dans ces conditions, la récupération et la valorisation de la chaleur perdue apparait comme un potentiel pour atteindre ces objectifs. L’intégration d’une pompe à chaleur à haute température permet une valorisation de pertes calorifiques en satisfaisant des besoins de chauffage à haute température (>130°C) qui apparaissent simultanément dans certains procédés (distillation, séchage…). Malheureusement, les pompes à chaleur répondant à ces besoins industriels sont indisponibles actuellement. C’est dans ce contexte que s’inscrit la présente étude qui a permis le développement et la mise en place d’une pompe à chaleur à haute température utilisant l’eau comme fluide frigorigène. Les verrous techniques et technologiques limitant la faisabilité d’une telle machine ont été levés en concevant une nouvelle architecture de PAC et en développant deux types de compresseur : un compresseur bi-vis adapté et un compresseur centrifuge bi-étagé à paliers magnétiques. La mise en place de cette PAC munie du compresseur bi-vis est présentée. Un modèle dynamique de cette pompe à chaleur est développé avec Modelica en tenant compte de la présence de gaz incondensables dans la machine. Des modèles détaillés des compresseurs sont développés en fonction de leurs caractéristiques géométriques. Une étude expérimentale de la phase de démarrage est présentée montrant le processus de purge des incondensables et l'évolution de certains paramètres de la pompe à chaleur. Ces résultats expérimentaux ont été confrontés à des simulations numériques. Plusieurs modes de fonctionnement de la machine de récupération des pertes calorifiques sont simulés numériquement et analysés énergétiquement ainsi qu’exergétiquement. Le modèle de pompe à chaleur a enfin été intégré à un modèle de colonne à distiller montrant les économies d'énergie globales et les avantages environnementaux obtenus
Currently, improving energy efficiency becomes a main challenge for all industrial energy systems. This challenge involves an improved recovery of wasted heat generated by several industrial processes. Large energy savings and potential environmental benefits are associated with the use of industrial heat pump mainly at high temperature levels (>130°C) unavailable on the market. The development of high temperature heat pump using water vapor as working fluid is investigated. Technical problems restraining the feasibility of this industrial heat pump are surmounted by a specifically designed heat pump, the development of a new twin screw compressor and a new centrifugal compressor with magnetic bearings. A dynamic model of this heat pump is developed using Modelica and taking into account the presence of non-condensable gases in the machine. Detailed models of the compressors are developed based on their geometrical characteristics. Experimental results of the start-up phase have been presented showing the non-condensable purging process and the evolution of some parameters of the heat pump. These experimental results have been confronted to numerical simulations. Several scenarios of industrial processes for high-temperature heat recovery and heat upgrading are numerically simulated and analyzed based on energetic and exergetic studies. The heat pump model has been integrated to a distillation column showing the global energy savings and the environmental benefits of using this developed heat pump
APA, Harvard, Vancouver, ISO, and other styles
10

Larnaudie, Guy. "Etude thermodynamique de fluides de travail pour pompes à chaleur fonctionnant à très hautes températures. Utilisation du mélange mercure-sodium." Rouen, 1996. http://www.theses.fr/1996ROUES010.

Full text
Abstract:
L'utilisation de pompes à chaleur fonctionnant à très hautes températures permettrait de pallier au déficit de chaleur à haut niveau (500°C) très souvent constaté sur les grandes installations industrielles qui, par contre, présentent généralement un excédent de chaleur à bas niveau (200°C). Les travaux présentés dans ce mémoire s'inscrivent dans le cadre d'une étude des pompes à chaleur à absorption susceptibles d'être utilisées dans le domaine des températures comprises entre 200°C et 1 200°C ; ceci au moyen de fluides de travail constitués d'un mélange de métaux liquides ou de sels fondus et, plus particulièrement, des mélanges mercure-sodium et trichlorure d'aluminium-chlorure de sodium. Pour chaque système, les propriétés physico-chimiques ont été estimées et l'équilibre liquide-vapeur a été décrit à l'aide de modèles thermodynamiques. Dans le cas du système mercure-sodium, ce modèle a été validé à l'aide des mesures de pression de vapeur réalisées sur une installation pilote. Associés aux bilans de matière et d'énergie établis dans le cas d'une pompe à chaleur idéale, ces modèles ont permis de déterminer, en fonction des conditions de fonctionnement (température, pression,. . . ) Les coefficients de performance de tels thermotransformateurs. La désorption du mercure, par ébullition nucléée d'amalgames de sodium, a été étudiée au moyen d'expériences spécifiques et, dans l'optique du dimensionnement de prototypes, les coefficients de transfert de chaleur ont été déterminés. Plusieurs projets de pompes à chaleur, à caractère expérimental ou industriel, sont proposés. Ces derniers utilisent le système mercure-sodium et leurs coefficients de performance théoriques sont compris entre 1,5 et 1,9.
APA, Harvard, Vancouver, ISO, and other styles

Books on the topic "Working fluid temperature"

1

Internal thermal control system hose heat transfer fluid thermal expansion evaluation test report. Marshall Space Flight Center, Ala: National Aeronautics and Space Administration, George C. Marshall Space Flight Center, 2001.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
2

United States. National Aeronautics and Space Administration. and Lewis Research Center, eds. Cool-down and frozen start-up behavior of a grooved water heat pipe. [Washington, D.C.]: National Aeronautics and Space Administration, 1990.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
3

Cool-down and frozen start-up behavior of a grooved water heat pipe. [Washington, D.C.]: National Aeronautics and Space Administration, 1990.

Find full text
APA, Harvard, Vancouver, ISO, and other styles

Book chapters on the topic "Working fluid temperature"

1

Smelt, R. "Power economy in high-speed wind tunnels by choice of working fluid and temperature." In High Reynolds Number Flows Using Liquid and Gaseous Helium, 265–84. New York, NY: Springer New York, 1991. http://dx.doi.org/10.1007/978-1-4612-3108-0_19.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Hui-tao, Wang, Wang Hua, and Ge Zhong. "Optimal Selection of Working Fluid for the Organic Rankine Cycle Driven by Low-Temperature Geothermal Heat." In Lecture Notes in Electrical Engineering, 121–29. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-26007-0_17.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Zhang, Chenghu, Yaping Li, and Jianli Zhang. "Working Fluid Selection and Thermodynamic Performance of the Steam Jet Large-Temperature-Drop Heat Exchange System." In Environmental Science and Engineering, 145–54. Singapore: Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-13-9524-6_16.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Rawlins, Wayne, Ray Radebaugh, and K. D. Timmerhaus. "Monitoring Rapidly Changing Temperatures of the Oscillating Working Fluid in a Regenerative Refrigerator." In Applications of Cryogenic Technology, 71–83. Boston, MA: Springer US, 1991. http://dx.doi.org/10.1007/978-1-4757-9232-4_7.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Novotny, Vaclav, Monika Vitvarova, and Michal Kolovratnik. "Absorption Power Cycles with Various Working Fluids for Exergy-Efficient Low-Temperature Waste Heat Recovery." In The Role of Exergy in Energy and the Environment, 99–111. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-89845-2_8.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Zhang, Xin, Hao Bai, Ning Li, Mengqi Li, Xinrong Zhang, and Hongxu Li. "Thermodynamic Properties of ORC System with Zeotropic Mixed Working Fluids for Low Temperature Waste Heat Recovery." In Energy Technology 2013, 85–92. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2013. http://dx.doi.org/10.1002/9781118658352.ch10.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Boobalan, Chitra, Sudha Ganesh, and Parthiban Rangaswamy. "Analysis of Liquid Cooling in Microchannels Using Computational Fluid Dynamics (CFD)." In Heat Transfer - Design, Experimentation and Applications [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.96248.

Full text
Abstract:
Liquid cooling is an extremely successful process to remove excess heat generated, with the usual procedure of heat transfer using coolant in desktop PCs. In this regard, heat transfer with minimal size equipment can be achieved by the addition of nanosized solid particles to the base fluid. The hybrid nanofluid is synthesized by dispersing the synthesized mono nanofluid in a volume fraction of 0.2 iron oxide with 0.8 fractions of graphene nanofluid to form a graphene/iron oxide combination. These nanoparticles increase the heat transfer coefficient as they have high thermal conductivity when compared to conventional heat transfer fluids like water or ethylene glycol. Stability is increased and sedimentation is reduced because of the large surface area of a nanoparticle. FLUENT, the most widely used computational fluid dynamics (CFD) software package, based on the finite volume method, and is used to run the thermal simulations for estimating the base temperature of the heat sink. The scope of this chapter is to find the base temperature of the heat sink using simulations. The experimentally measured base temperature is 310.01 K and in the simulation, it is 310.81 K for the flow rate of 0.75LPM. All the simulated surface temperatures are compared with experimentally determined temperatures for simulation validation.
APA, Harvard, Vancouver, ISO, and other styles
8

S. Leite, Brenno, Daniel J.O. Ferreira, Sibele A.F. Leite, and Vanessa F.C. Lins. "Numerical and Experimental Analysis of Thermochemical Treatment for the Liquefaction of Lemon Bagasse in a Jacketed Vessel." In Biomass [Working Title]. IntechOpen, 2020. http://dx.doi.org/10.5772/intechopen.94364.

Full text
Abstract:
In this work, it was investigated the time evolution of thermal profile inside a liquefaction vessel and how the temperature and time of reaction influenced liquefaction yield. Liquefaction was performed in two different ways: (1) Experimental Analysis; (2) Numerical 3-D model, using Computational Fluid Dynamics (CFD). Liquefaction was performed using lemon bagasse samples, glycerol and sulphuric acid, as catalyst. Temperature and liquefaction Yield (LY) were measured for different time of reaction (30, 60 and 90 minutes). From experimental data, LY were higher than 70 wt% for 90 minutes reaction. The increase in the temperature inside the reactor occurred due to the conduction and natural convection phenomena. Although the jacketed vessel was fed with steam at 125°C, working conditions allowed the heating of the mixture to less than 100°C. CFD thermal profile was in accordance with experimental data. They showed it was necessary 60 minutes to achieve a steady state of heating in the mixture inside this liquefaction vessel. From CFD transient simulations, it was observed some oscillations and detachment from experimental data, which may be due to changes in fluids properties along the process. Despite this consideration CFD could satisfactory analyse heat transfer in this liquefaction process.
APA, Harvard, Vancouver, ISO, and other styles
9

Milanezi de Andrade, Rafhael, André Palmiro Storch, Lucas de Amorim Paulo, Antônio Bento Filho, Claysson Bruno Santos Vimieiro, and Marcos Pinotti. "Transient Thermal Analysis of a Magnetorheological Knee for Prostheses and Exoskeletons during Over-Ground Walking." In Heat Transfer - Design, Experimentation and Applications [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.95372.

Full text
Abstract:
Proper knee movement is essential for accomplishing the mobility daily tasks such as walking, get up from a chair and going up and down stairs. Although the technological advances in active knee actuators for prostheses and exoskeletons to help impaired people in the last decade, they still present several usage limitations such as overweight or limited mechanical power and torque. To address such limitations, we developed the Active Magnetorheological Knee (AMRK) that comprises a Motor Unit (MU), which is a motor-reducer (EC motor and Harmonic Drive) and a MR clutch, that works in parallel to a magnetorheological (MR) brake. Magnetorheological fluids, employed in the MR clutch and brake, are smart materials that have their rheological properties controlled by an induced magnetic field and have been used for different purposes. With this configuration the actuator can work as a motor, clutch or brake and can perform similar movements than a healthy knee. However, the stability, control, and life of magnetorheological fluids critically depend on the working temperature. By reaching a certain temperature limit, the fluid additives quickly deteriorate, leading to irreversible changes of the MR fluid. In this study, we perform a transient thermal analysis of the AMRK, when it is used for walking over-ground, to access possible fluid degradation and user’s discomfort due overheating. The resulting shear stress in the MR clutch and brake generates heat, increasing the fluid temperature during the operation. However, to avoid overheating, we proposed a mode of operation for over-ground walking aiming to minimize the heat generation on the MR clutch and brake. Other heat sources inside the actuator are the coils, which generate the magnetic fields for the MR fluid, bearings, EC motor and harmonic drive. Results show that the MR fluid of the brake can reach up to 31°C after a 6.0 km walk, so the AMRK can be used for the proposed function without risks of fluid degradation or discomfort for the user.
APA, Harvard, Vancouver, ISO, and other styles
10

Minh Phu, Nguyen, and Nguyen Van Hap. "Numerical Investigation of Natural Convection and Entropy Generation of Water near Density Inversion in a Cavity Having Circular and Elliptical Body." In Fluid-Structure Interaction [Working Title]. IntechOpen, 2020. http://dx.doi.org/10.5772/intechopen.95301.

Full text
Abstract:
In this chapter, a water-filled square cavity with left hot wall and right cold wall was numerically investigated. The hot and cold wall temperatures are 10°C and 0°C respectively to examine the density inversion of natural convection water, i.e. water at 4°C. In the middle of the square, there are circular and elliptical bodies to study fluid–structure interaction in terms of the thermohydraulic behavior and entropy generation. 2D numerical simulation was performed using finite volume method in Ansys fluent software with the assumption of laminar flow. The simulation results are compared with benchmark data to determine reliability. The results indicate that the body insertions increase the convection heat transfer coefficients at the best heat transfer positions due to impingement heat transfer. An increase in heat transfer rate of 1.06 times is observed in the case of circular body compared to none. There are three primary eddies in the cavity with bodies, whereas the cavity without body has two primary eddies. Maximum entropy generation was found in the upper right corner of cavity mainly due to high horizontal temperature gradient. Bodies of circle and vertical ellipse have almost the same thermohydraulic and entropy generation characteristics due to the same horizontal dimension which mainly effects on the downward natural convection current. The entropy generation of cavity with circular body is 1.23 times higher than that of the cavity without body. At positions y/L = 1 on the hot wall and y/L = 0.74 on the cold wall, the convection heat transfer coefficient is close to zero due to stagnant fluid.
APA, Harvard, Vancouver, ISO, and other styles

Conference papers on the topic "Working fluid temperature"

1

Paris, Anthony D., Pradeep Bhandari, and Gajanana C. Birur. "High Temperature Mechanically Pumped Fluid Loop for Space Applications –Working Fluid Selection." In International Conference On Environmental Systems. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2004. http://dx.doi.org/10.4271/2004-01-2415.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Sammak, Majed, Marcus Thern, and Magnus Genrup. "Influence of Working Fluid on Gas Turbine Cooling Modeling." In ASME Turbo Expo 2013: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/gt2013-95457.

Full text
Abstract:
Cooling is essential in all modern high-temperature gas turbines. Turbine cooling is mainly a function of gas entry temperature, which plays the key role in overall gas turbine performance. High turbine entry temperatures can be achieved through appropriate selection of blade cooling method and blade material. The semi-closed oxy-fuel combustion combined cycle (SCOC-CC) operates at the same high entry gas temperature, hence blade cooling is necessary. The aim of this paper was to calculate the required turbine cooling in oxy-fuel gas turbines and compare it to the required turbine cooling in conventional gas turbines. The approach of the paper was to evaluate the thermodynamic and aerodynamic factors affecting turbine cooling with using the m*-model. The results presented in the paper concerned a single turbine stage at a reference diameter. The study showed greater cooling effectiveness in conventional gas turbines, but a greater total cooled area in oxy-fuel gas turbines. Consequently, the calculated total required cooling mass flow was close in the both single stage turbines. The cooling requirement and cooled area for a conventional and oxy-fuel twin-shaft gas turbine was also examined. The gas turbine was designed with five turbine stages. The analysis involved various turbine power and combustion outlet temperatures (COT). The results showed that the total required cooling mass flow was proportional to turbine power because of increasing gas turbine inlet mass flow. The required cooling mass flow was proportional to COT as the blade metal temperature is maintained at acceptable limit. The analysis revealed that required cooling for oxy-fuel gas turbines was higher than for conventional gas turbines at a specific power or specific COT. This is due to the greater cooled area in oxy-fuel gas turbines. The cooling effectiveness of conventional gas turbines was greater, which indicated higher required cooling. However, the difference in cooling effectiveness between conventional and oxy-fuel gas turbines was less in rear stages. The cooling mass flow as percentage of gas turbine inlet mass was slightly higher in conventional gas turbines than in oxy-fuel gas turbines. The required cooling per square meter of cooled area was used as a parameter to compare the required cooling for oxy-fuel and conventional gas turbines. The study showed that the required cooling per cooled area was close in both studied turbines.
APA, Harvard, Vancouver, ISO, and other styles
3

Yang, Yue, Yamei Li, Yang Fu, Guoyou Xu, Ziyi Zhen, Yating Wang, and Xiang Gou. "Research on the Selection of Low Temperature Aluminum Heat Pipe Working Fluid." In 2016 2nd Workshop on Advanced Research and Technology in Industry Applications (WARTIA-16). Paris, France: Atlantis Press, 2016. http://dx.doi.org/10.2991/wartia-16.2016.268.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Dakkah, Baydaa Bo, Ildar A. Sultanguzin, Yury V. Yavorovsky, Bassam E. Badran, Hussein A. Tina, and Mohammad Yman Yassin Alsabbagh. "Choosing the Suitable Working Fluid to Recover Heat from Low-Temperature Sources." In 2021 3rd International Youth Conference on Radio Electronics, Electrical and Power Engineering (REEPE). IEEE, 2021. http://dx.doi.org/10.1109/reepe51337.2021.9388073.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Minor, Barbara, Konstantinos (Kostas) Kontomaris, and Bianca Hydutsky. "Nonflammable Low GWP Working Fluid for Organic Rankine Cycles." In ASME Turbo Expo 2014: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/gt2014-26855.

Full text
Abstract:
Regulatory pressure has been increasing globally to address the issue of climate change. In particular, there are plans to reduce the use of hydrofluorocarbon (HFC) based working fluids across many applications, as HFCs are forecast to be significant contributors to global warming in the future. Therefore, there is a need to find low global warming potential (GWP) fluids suitable for organic rankine cycles (ORCs) in those systems where HFCs have historically been preferred. These are usually systems that require a non-flammable working fluid. A new ORC working fluid, cis-1,1,1,4,4,4-hexafluoro-2-butene, also called DR-2 (cis-CF3CH=CHCF3) has been developed which is nonflammable with very low GWP of 8.9 and an ozone depletion potential (ODP) of zero because it contains no chlorine or other halogen atoms other than fluorine. DR-2 also has a favorable toxicity profile based on testing to date. DR-2 is thermally stable in the presence of lubricant and metals, air and oxygen up to the maximum temperature tested of 250°C. DR-2 has a boiling point of 33.4°C and a relatively high critical temperature of 171.3°C, which result in relatively low vapor pressures and high cycle energy efficiencies. It can enable more environmentally sustainable ORC platforms to generate electrical power from widely available heat at higher temperatures and with higher energy efficiencies than incumbent working fluids.
APA, Harvard, Vancouver, ISO, and other styles
6

Dong, Jingming, Yuxin Xia, Hongbin Ma, He Song, Zhongxi Zhao, and Tao Liang. "Experimental Investigation of a Miniature Ejector Using Water As Working Fluid." In ASME 2019 6th International Conference on Micro/Nanoscale Heat and Mass Transfer. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/mnhmt2019-3925.

Full text
Abstract:
Abstract This paper presents an experimental investigation of a miniature ejector using water as the working fluid. The investigated ejector cooling system can be used to keep the temperature of an electric chip below ambient temperature. The authors tested the effects of working conditions, the nozzle exit position (NXP), and the area ratio on the ejector’s performance. Experimental results show that the miniature ejector works well in the high-temperature evaporator (HTE) under temperatures ranging from 55 °C to 70 °C and can achieve a 0.66 coefficient of performance (COP). With the increase of the NXP, the COP decreased, while the critical condensing pressure first increased and then decreased. As the area ratio of the miniature ejector increased, the COP increased, and the critical condensing pressure decreased.
APA, Harvard, Vancouver, ISO, and other styles
7

Sarraf, David B., and William G. Anderson. "Heat Pipes for High Temperature Thermal Management." In ASME 2007 InterPACK Conference collocated with the ASME/JSME 2007 Thermal Engineering Heat Transfer Summer Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/ipack2007-33984.

Full text
Abstract:
Copper water heat pipes are a well-established solution for many conventional electronics cooling applications; however they have several problems when applied to high temperature electronics. The high vapor pressure of the working fluid combined with the decreasing strength of an already soft material leads to excessive wall thickness, high mass, and an inability to make thermally useful structures such as planar heat pipes (vapor chambers) or heat pipes with flat input surfaces. Titanium/water and Monel/water heat pipes can overcome the disadvantages of copper/water heat pipes and produce a viable thermal management solution for high temperature electronics. Water remains the fluid of choice at temperature up to about 280°C due to its favorable transport properties. Life tests have shown compatibility at high temperature. At temperatures above roughly 300°C, water is no longer a suitable fluid, due to high vapor pressure and low surface tension as the critical point is approached. At higher temperatures, another working fluid/envelope combination is required, either an organic or halide working fluid. Preliminary halide life test results are presented, giving fluids that can operate at temperatures as high as 425°C. At higher temperatures, alkali metal heat pipes are suitable. Water and the higher temperature working fluids can offer solutions for cooling high-temperature electronics, or those working at or above 150°C.
APA, Harvard, Vancouver, ISO, and other styles
8

Puleo, Bernadette, and Robert Bruckner. "A Parametric Study of Foil Journal Bearings by Temperature, Pressure, and Working Fluid." In 6th International Energy Conversion Engineering Conference (IECEC). Reston, Virigina: American Institute of Aeronautics and Astronautics, 2008. http://dx.doi.org/10.2514/6.2008-5734.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Ali, Muhammad Ansab, Tariq Saeed Khan, Ebrahim Al Hajri, and Zahid H. Ayub. "A Computer Program for Working Fluid Selection of Low Temperature Organic Rankine Cycle." In ASME 2015 Power Conference collocated with the ASME 2015 9th International Conference on Energy Sustainability, the ASME 2015 13th International Conference on Fuel Cell Science, Engineering and Technology, and the ASME 2015 Nuclear Forum. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/power2015-49691.

Full text
Abstract:
Fossil fuels are continuously depleting while the global energy demand is growing at a fast rate. Additionally, fossil fuels based power plants contribute to environmental pollution. Search for alternate energy resources and use of industrial waste heat for power production are attractive topics of interest these days. One way of enhancing power production and decreasing the environmental impact is by recuperating and utilizing low grade thermal energy. In recent years, research on use of organic Rankine cycle (ORC) has gained popularity as a promising technology for conversion of heat into useful work or electricity. Due to simple structure of ORC system, it can be easily integrated with any energy source like geothermal energy, solar energy and waste heat. A computer program has been developed in engineering equation solver (EES) environment that analyzes and selects appropriate working fluid for organic Rankine cycle design based on available heat sources. For a given heat source, the program compares energy and exergy performance of various working fluids. The program also includes recuperator performance analysis and compares its effectiveness on the overall thermal performance of the Rankine cycle. This program can assist in preliminary design of ORC with respect to best performing refrigerant fluid selection for the given low temperature heat source.
APA, Harvard, Vancouver, ISO, and other styles
10

Sundeep, Allu Ram, and S. G. Rakesh. "Effect of temperature of working fluid on the performance of centrifugal thermal pumps." In SEVENTH INTERNATIONAL SYMPOSIUM ON NEGATIVE IONS, BEAMS AND SOURCES (NIBS 2020). AIP Publishing, 2021. http://dx.doi.org/10.1063/5.0058225.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Reports on the topic "Working fluid temperature"

1

Baxter, V. (State and transport properties of high temperature working fluids and nonazeotropic mixtures). Office of Scientific and Technical Information (OSTI), May 1990. http://dx.doi.org/10.2172/7124513.

Full text
APA, Harvard, Vancouver, ISO, and other styles
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography