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... The objectives of this study are to analyze effects of design parameters of a generator with a steam heat source on condensation heat transfer and flow characteristics inside tubes and to design optimum configuration of the generator with minimum volume that satisfies design constraints for H2O/LiBr absorption chiller application. To that end, the heat transfer and flow characteristics of a straig ...
heattransfer, etc ; fabrics; flame retardants; gases; pyrolysis; risk; synergism; Show all 7 Subjects
Abstract:
... Superior flame retardant textiles are urgently needed to address high fire and heat risks. This study provides a simple and effective strategy to improve the flame retardancy of textiles through a synergistic effect between the blended fibers, and a system with synergistic in flame retardant vinylon (FRV)/poly(m-phenylene isophthalamide) (PMIA) blended fibers is discovered. The FRV/PMIA 50/50 exhi ...
heattransfer, etc ; energy efficiency; models; temperature; urban areas; vegetation; Show all 6 Subjects
Abstract:
... Green façades or vertical greenery systems (VGSs) are continuously gaining attention among urbanists for improving the living comfort and energy efficiency in urban areas. However, modeling and simulating the thermal response of VGSs remains a research topic. This paper introduces a novel inverse modeling approach for modeling the thermal responseof VGSs on building envelopes. The modeling approac ...
heattransfer, etc ; energy; nanofluids; nanoparticles; nitrates; screening; silica; solar energy; Show all 8 Subjects
Abstract:
... A high-performance heat transfer fluid (HTF) plays a crucial role in the overall performance and efficiency of the concentrating solar power (CSP) systems for utilizing solar energy. Molten salt-based nanofluids, which may offer a promising solution to help reduce the size and cost of CSP system, have attracted increasing attention. However, there is still no comprehensive assessment strategy that ...
heattransfer, etc ; Reynolds number; friction; geometry; renewable energy sources; roughness; Show all 6 Subjects
Abstract:
... A study is carried out providing integrated roughness over absorber plate of solar air heater to improve its potential for heat transfer augmentation. A number of experiments are conducted with twisted roughness to pursuit test results for heat transfer augmentation along with friction factor phenomena. The experiments stand with a relevant range of flow parameters as Reynolds number from 3500 to ...
heattransfer; heattransfer coefficient, etc ; energy; grilling; minced meat; models; pan frying; product quality; surface temperature; turkey meat; Show all 10 Subjects
Abstract:
... Few studies concerning contact heating of food products were found in the literature despite the importance of this mode of heat transfer in many operations (grilling, pan-frying) and its drastic impact on product quality change during heating. An original heating device to measure continuously contact heat flux and heating surface temperature was therefore developed and applied to the contact hea ...
heattransfer; heattransfer coefficient, etc ; air; electric power; solar energy; Show all 5 Subjects
Abstract:
... In the present study, enhancing the heat transfer is experimentally investigated by the electro-hydrodynamics (EHD) through a single-pass air-cooled PV/T (Photovoltaic/Thermal System). The corona wind increases the heat transfer coefficient by producing a secondary flow and vortex, and consequently, increases the PV/T system efficiency. The effects of the corona wind are studied by changing the vo ...
heattransfer, etc ; calorimeters; combustion; fire hazard; fire spread; foams; gasification; insulating materials; melting; polyols; polyurethanes; shrinkage; Show all 12 Subjects
Abstract:
... The shrinkage is an important thermal response of flexible polyurethane foam (FPUF) in fire, which couples its first combustion stage and influences the initial fire spread. In this paper the combustion and shrinkage behaviours are quantitatively investigated and the shrinkage mechanisms are discussed. The critical heat flux for the shrinkage is about 13 kW/m2, between the critical heat flux for p ...
heattransfer, etc ; entropy; exergy; geometry; phase transition; solar thermal energy; temperature; Show all 7 Subjects
Abstract:
... Cascaded Thermal Storage (CTS) technique is an efficient solution for storing solar thermal energy of high quality. In this paper, heat transfer rate and thermodynamic irreversibility are combined for optimizing cascaded PCM thermal storage system based on entransy and entropy. Optimal solutions for temperature of CTS unit are obtained based on entransy and entropy, which cannot only present a ben ...
heattransfer, etc ; Reynolds number; computer software; electricity; irradiation; renewable energy sources; simulation models; solar collectors; temperature; Show all 9 Subjects
Abstract:
... Photovoltaic thermal (PV/T) collectors that supply both electricity and heat are growingly becoming popular in household and other applications. However, efficient heat removal from backside of PV module is still a challenge that hampers its electrical as well as thermal performance. In the present research, an absorber-plate less thermal collector has been introduced and mathematical model of suc ...
heattransfer, etc ; absorbance; carbon dioxide; case studies; combustion; databases; models; prediction; thermal radiation; water vapor; Show all 10 Subjects
Abstract:
... To develop an efficient and practical spectral radiation model for CFD simulations, a banded approach is proposed for a mixture of carbon dioxide and water vapor in varying thermodynamic states. Using a previously reported band dividing scheme, a statistical narrow band model is implemented to provide gray band absorption coefficient databases. The databases were then approximated by certain simpl ...
heattransfer, etc ; biomass; fluidized beds; gasification; hydrodynamics; mathematical models; mixing; model validation; prediction; renewable energy sources; Show all 10 Subjects
Abstract:
... 2D and 3D simulations were carried out to predict the whole gasification process behaviour in a pilot-scale bubbling fluidized bed reactor. Special concern for the complex hydrodynamics phenomena within the fluidized bed was undertaken. The implemented multiphase Eulerian-Eulerian mathematical model was validated by comparison to experimental gasification runs and fluidization curves gathered from ...
heattransfer, etc ; Reynolds number; equipment performance; friction; models; renewable energy sources; roughness; Show all 7 Subjects
Abstract:
... Solar air heater (SAH) is a device used to convert sun radiations into heating applications. To improve its performance, the heat absorbing side of SAH is modified with the ribs called roughness. The flow characteristics and augmentation of heat due to square shaped ribs in SAH having triangular cross-sectional passage has been simulated using computational fluid dynamic (CFD) technique. The CFD s ...
heattransfer, etc ; heat exchangers; models; renewable energy sources; soil temperature; thermal energy; thermal properties; Show all 7 Subjects
Abstract:
... The transient thermal performance of a vertical double U-tube borehole heat exchanger (BHE) was numerically studied by validated heat transfer model. Further, the influence of several operation parameters, including inlet velocity, temperature and operation interval, on radial/axial soil temperature distribution were investigated. The simulation result showed that the increased amplitude of the BH ...
heattransfer, etc ; cooling; decision making; electronics; energy efficiency; entropy; friction; models; nanofluids; powders; surface temperature; Show all 11 Subjects
Abstract:
... In this contribution, the hydrothermal and irreversibility attributes of a biological nanofluid in a new heat sink enhanced with flow distributor are investigated. By increasing either concentration or velocity, the surface temperature reduces, and the cooling uniformity improves. The velocity has a more significant effect on the temperature in comparison with the effect of concentration. Increasi ...
heattransfer, etc ; Rhizopus microsporus var. oligosporus; agar; biomass; bioreactors; hyphae; inoculum; mathematical models; solid state fermentation; Show all 9 Subjects
Abstract:
... During solid-state fermentation, aerial hyphae occupy the interparticle spaces, binding adjacent particles and decreasing the efficiency of mass and heat transfer within the bioreactor bed. The present work explores two questions related to this phenomenon: (i) what determines the direction of growth of vegetative aerial hyphae and (ii) what makes them stop growing? We developed a discrete mathema ...
heattransfer, etc ; carbon dioxide; combustion; fuels; greenhouse gases; internal combustion engines; mixing; Show all 7 Subjects
Abstract:
... Improving the efficiency of the powertrain system is of great importance to reduce the greenhouse gas CO2. Advanced combustion engine with Partially Premixed Combustion (PPC) is one of the best solutions. It is proved to have a high engine efficiency and low emission level. Using multiple injections is a good way to achieve PPC. The efficiencies using multiple injections were evaluated on a metal ...
heattransfer, etc ; annuals; computer software; electricity; power plants; salts; solar collectors; solar energy; temperature; thermal energy; Show all 10 Subjects
Abstract:
... Concentrated solar power plants using molten salts as heat transfer and storage fluid have emerged as the preferred commercial solution for solar thermal electricity in central receiver technology. Despite their ability to store large amounts of thermal energy and efficient receiver designs, further efficiency improvements are constrained by tight temperature restrictions when using molten salts ( ...
heattransfer, etc ; Taguchi method; air; algorithms; multi-criteria decision making; phase transition; solar energy; thermal energy; Show all 8 Subjects
Abstract:
... Thermal energy storage (TES) using phase change materials (PCMs) is being widely considered as one of the alternative solutions for effective use of solar energy. This paper presents a multi-objective optimisation strategy for TES systems using PCMs for solar air systems, in which two performance indicators of average heat transfer effectiveness and effective PCM charging time were used as the con ...
heattransfer, etc ; energy; gravity; hydrogen; liquids; models; phase transition; physical activity; renewable energy sources; temperature profiles; Show all 10 Subjects
Abstract:
... A calculation model is developed to investigate the pressurization performance and thermal stratification in a liquid hydrogen (LH2) tank. Viscous flow is considered in the stratification model to ensure the continuity of fluid flow and heat exchange. The tank pressure rise, energy distribution and thermal stratification are studied respectively. Compared to the results without considering the pha ...