High Temporally and Spatially Resolved Thermal Energy Detection after Nonradiative Transition in Solution Using a Molecular Heater−Molecular Thermometer Integrated System

1999 ◽  
Vol 121 (21) ◽  
pp. 5079-5080 ◽  
Author(s):  
Toshiya Okazaki ◽  
Noboru Hirota ◽  
Toshi Nagata ◽  
Atsuhiro Osuka ◽  
Masahide Terazima
Keyword(s):  
Thermal Energy ◽  
Energy Detection ◽  
Integrated System ◽  
Nonradiative Transition ◽  
Spatially Resolved

Robust Design of Advanced Thermoelectric Conversion Systems: Probabilistic Design Impacts on Specific Power and Power Flux Optimization

2008 ◽  
Vol 1102 ◽  
Author(s):  
Terry J Hendricks ◽  
Naveen K. Karri
Keyword(s):  
System Design ◽  
Thermal Energy ◽  
Integrated System ◽  
System Level ◽  
Specific Power ◽  
Design Parameters ◽  
Probabilistic Design ◽  
Power Flux ◽  
Research Attention ◽  
System Designs

AbstractAdvanced, direct thermal energy conversion technologies are receiving increased research attention in order to recover waste thermal energy in advanced vehicles and industrial processes. Advanced thermoelectric (TE) systems necessarily require integrated system-level analyses to establish accurate optimum system designs. Past system-level design and analysis has relied on well-defined deterministic input parameters even though many critically important environmental and system design parameters in the above mentioned applications are often randomly variable, sometimes according to complex relationships, rather than discrete, well-known deterministic variables. This work describes new research and development creating techniques and capabilities for probabilistic design and analysis of advanced TE power generation systems to quantify the effects of randomly uncertain design inputs in determining more robust optimum TE system designs and expected outputs. Selected case studies involving stochastic TE .material properties demonstrate key stochastic material impacts on power, optimum TE area, specific power, and power flux in the TE design optimization process. Magnitudes and directions of these design modifications are quantified for selected TE system design analysis cases.

scholarly journals Theoretical and Experimental Evaluation of the Working Fluid Temperature Levels in a CPV/T System

Energies ◽  
2020 ◽  
Vol 13 (12) ◽  
pp. 3077
Author(s):  
Carlo Renno
Keyword(s):  
Thermal Energy ◽  
Integrated System ◽  
Hot Water ◽  
Experimental Comparison ◽  
Working Fluid ◽  
Fluid Temperature ◽  
Cooling Fluid ◽  
Operation Conditions ◽  
Temperature Levels ◽  
T System

A linear focus Concentrator Photovoltaic and Thermal (CPV/T) system can match the thermal demands of a user. The evaluation of the cooling fluid temperature levels of a CPV/T system is fundamental to understand if this system is capable of satisfying the typical thermal requirements of a residential user (heating, cooling and domestic hot water). First, an experimental line-focus CPV/T system, realized in the Laboratory of Applied Thermodynamics of the University of Salerno (Italy), has allowed to determine the cooling fluid temperature at the CPV/T system outlet. Successively, the cooling fluid temperatures, experimentally obtained, have been compared with the same temperatures calculated by means of a theoretical model under the same operation conditions. A deviation in terms of the percentage relative error between theoretical and experimental results included between about 0.5% and 5%, has been found. The goodness of the theoretical–experimental comparison in terms of the temperature of the operation fluid at the CPV/T system outlet has represented a fundamental point to evaluate theoretically, by means of the TRNSYS software, the other levels of temperature of an integrated system, constituted by CPV/T system, thermal tank and user, for different temporal scenarios (hourly, weekly, monthly and yearly). The input data of the TRNSYS model are: Direct Normal Irradiance (DNI), Triple-Junction (TJ) cell temperature and environmental conditions. A tank model is also adopted to satisfy the thermal energy demand peaks, and the temperature stratification in the tank linked to the CPV/T system, as function of the height, is obtained in winter and summer. It is important to define these thermal levels to verify if a CPV/T system is capable to satisfy the residential user energy demands or a thermal energy integration is necessary in some periods of the year. A good stratification has been noted in the summer season, with temperature values that are variable between about 40 and 90 °C. From April to October, the tank average temperature is generally resulted about 10 °C higher than the temperature required by the fluid sent to the residential user, and a very low integration is then necessary. It has been verified that the CPV/T system covers a large part of the thermal energy needs of the residential user during the year; the coverage is limited only in the winter months.

scholarly journals An Experimental Investigation on Energy Performance of The Hybrid Photovoltaic Thermal System

2020 ◽  
Vol 197 ◽  
pp. 08003
Author(s):  
Shahrokh Barati ◽  
Livio de Santoli ◽  
Gianluigi Lo Basso ◽  
Antonio Galizia ◽  
Giulia Spiridigliozzi
Keyword(s):  
Hybrid System ◽  
Thermal Energy ◽  
Fossil Fuels ◽  
Ghg Emissions ◽  
Energy System ◽  
Energy Performance ◽  
Integrated System ◽  
Hybrid Energy ◽  
Photovoltaic Thermal System ◽  
T System

Climate change is a worldwide recognized problem, and its mitigation identified as one of the most significant challenges. The way to achieve this purpose is to reduce greenhouse gases (GHG) emissions through the energy system using renewables. The change from an energy system based on fossil fuels to renewable sources-based one is necessary on which the world community agrees. A photovoltaic thermal (PV/T) panel is a system that can produce both electricity and thermal energy simultaneously in one integrated system. This paper deals with hybrid energy systems, specifically a hybrid system to produce power and thermal energy from solar sources consisting of photovoltaic thermal modules. The hybrid system consists of 7 hybrid photovoltaic panels installed on the roof of the laboratory. This paper presents a study for experimental data obtained from a measurement campaign of the thermal and electrical behavior of a PV/T system in single and series models.

Applications of Solar Powered Cooling System Using Integrated Variable Effect Absorption Chillers With Ice Thermal Energy Storage in UAE

2020 ◽  
Author(s):  
Taabish Siddiqui ◽  
Fadi Ghaith
Keyword(s):  
Energy Storage ◽  
Thermal Energy ◽  
Thermal Energy Storage ◽  
Cooling System ◽  
Residential Buildings ◽  
Integrated System ◽  
Ice Storage ◽  
Absorption Chiller ◽  
Variable Effect ◽  
Space Cooling

Abstract This paper addresses the potential of integrating parabolic trough collector (PTC) with variable effect absorption chiller assisted with ice thermal energy storage (ITES) for the purpose of space cooling in residential buildings. In this work, the thermal performance of the proposed integrated system was evaluated in order to assess the system’s capability to fulfil the cooling demands. The proposed system was modelled numerically and simulations were performed using TRNSYS software. Initially during the day, the chiller was operated in a single stage mode to provide required direct cooling to the building. Once the thermal output of the PTC is adequate, a double-effect absorption cooling was activated, with the production of sub-zero evaporator temperatures in order to charge the ice storage prior to providing chilled water to the load during night time. The obtained results showed that the proposed system is capable to provide a continuous space cooling for 20 hours from which 11 hours of cooling were generated using the absorption chiller, whilst the ice storage acts as a backup source of cooling for additional 9 hours during nighttime. For the remainder of the time of almost 4 hours, a biomass auxiliary heater was used to activate the chiller during startup period thus eliminating completely the need of a conventional cooling system. The performed cost analysis proved the feasibility of the proposed system with pay-back period of 3.5 years.

Electron Channeling Patterns

1977 ◽  
Vol 35 ◽  
pp. 12-13
Author(s):  
David C. Joy
Keyword(s):  
Electron Diffraction ◽  
Incidence Angle ◽  
Photographic Plate ◽  
Diffraction Effect ◽  
Angle Of Incidence ◽  
Bulk Single Crystal ◽  
Time Resolved ◽  
Electron Channeling ◽  
Spatially Resolved ◽  
Large Bulk

Electron channeling patterns (ECP) were first found by Coates (1967) while observing a large bulk, single crystal of silicon in a scanning electron microscope. The geometric pattern visible was shown to be produced as a result of the changes in the angle of incidence, between the beam and the specimen surface normal, which occur when the sample is examined at low magnification (Booker, Shaw, Whelan and Hirsch 1967).A conventional electron diffraction pattern consists of an angularly resolved intensity distribution in space which may be directly viewed on a fluorescent screen or recorded on a photographic plate. An ECP, on the other hand, is produced as the result of changes in the signal collected by a suitable electron detector as the incidence angle is varied. If an integrating detector is used, or if the beam traverses the surface at a fixed angle, then no channeling contrast will be observed. The ECP is thus a time resolved electron diffraction effect. It can therefore be related to spatially resolved diffraction phenomena by an application of the concepts of reciprocity (Cowley 1969).

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