Literatura científica selecionada sobre o tema "Power temperature coefficient"

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Artigos de revistas sobre o assunto "Power temperature coefficient"

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Fokeev, A. E., e I. N. Tumakov. "Analysis of Operating Modes of Oil-Immersed Power Transformers with a Voltage of 10 (6) / 0.4 kV". Vestnik IzhGTU imeni M.T. Kalashnikova 24, n.º 4 (2021): 80–91. http://dx.doi.org/10.22213/2413-1172-2021-4-80-91.

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The rate of thermal aging of the power transformers windings insulation depends on the effects of the electric field, mechanical stresses, temperature and processes that cause changes in these factors. A calculation algorithm is considered that allows determining the temperature of the most heated point of the windings of an oil power transformer at known values of the load current and ambient temperature. Calculation of the most heated winding point temperature and the rate of thermal aging of insulation for an oil power transformer at different ambient temperatures during the year, different values and different spectral composition of the electric load current showed that in some cases it is possible to violate the permissible operating conditions of power transformers. According to the calculation results, the dependences of the thermal aging rate of insulation on the ambient temperature are constructed, with different load parameters and different load coefficients of power transformers. For the considered modes, in the warm season, the value of the thermal aging rate of insulation significantly exceeds the nominal value. Based on mathematical models of oil power transformers with natural and forced oil circulation, expressions are obtained for determining the coefficient of reduction of the oil power transformers permissible load when the ambient temperature exceeds the normal value of 20 °C. On the basis of these expressions, for practical use, the dependences of the coefficient of reduction of the permissible load on the ambient temperature are constructed. The influence of ambient temperature must be taken into account when choosing the power of oil power transformers, for which it is assumed to operate in full redundancy mode or high load factor values (³ 0.8) in normal mode. To ensure the normative service life of the insulation of the windings, it is necessary to determine the design power of oil power transformers using the coefficient of reduction of the permissible load under the influence of higher harmonics of the current and the coefficient of reduction of the permissible load under the influence of ambient temperature.
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Radziemska, E., e E. Klugmann. "Photovoltaic Maximum Power Point Varying with Illumination and Temperature". Journal of Solar Energy Engineering 128, n.º 1 (24 de janeiro de 2005): 34–39. http://dx.doi.org/10.1115/1.2147586.

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This paper presents the experimental results and discusses the track of the maximum power point on the current-voltage curve of a PV module due to changes of the illumination level and temperature. A time decrease of the voltage and simultaneous temperature increase during the initial stage of irradiation has been observed. Some practical implementation aspects of a maximum power point tracking unit, which match the current and voltage characteristics of the load to the PV module’s maximum power point automatically, are also discussed. A linear decrease of the maximum output power Pm with temperature increase has been observed and the temperature coefficient was derivate. Temperature coefficients for Voc, Isc, Vmpp, Impp, and ηPV have been determined for the photovoltaic module. Also the radiation-rate coefficient at constant temperature has been calculated.
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Tsao, Bang Hung, Jacob Lawson, James D. Scofield, Clinton Laing e Jeffery Brown. "3D Thermal Stress Model for SiC Power Modules". Materials Science Forum 600-603 (setembro de 2008): 1227–30. http://dx.doi.org/10.4028/www.scientific.net/msf.600-603.1227.

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Three dimensional models of both single-chip and multiple-chip power sub-modules were generated using ANSYS in order to simulate the effects of various substrate materials, heat fluxes, heat transfer coefficients, and device placement configurations on temperature and thermal stress contours. Alumina, aluminum-nitride, and CVD diamond were compared as substrates. Heat fluxes of 100 to 500 watts/cm2 resulted in SiC device junction temperatures in the range of 350 to 650 K. The predicted maximum operating temperature for a chip, to which 300 watts/cm2 of heat flux was applied, would be 239°C (512 K). In the applied heat flux range, the minimum and maximum Von Mises stress of a simulated single SiC device sub-module was between 1.2 MPa to 2.4 GPa. The maximum shear stress at 300 watts/cm2 was predicted to be 243 MPa. Both the maximum and minimum chip temperature decreased with increasing heat transfer coefficient from 25 to 2500 watts/m2 K. With modest cooling, represented by a heat transfer coefficient (hconv) of 250 watts/m2 K, SiC chips operated at 300 watts/cm2 power density maintained junction temperatures Tj < 400 K. If consistent with simulation results, CVD diamond integrated substrates should be superior to those comprised of AlN or Al2O3. Asymmetric device placement in the multi-chip module proved more effective at avoiding potential hot spots than the symmetric configuration.
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Konovalov, Dmytro, Ignat Tolstorebrov, Yuhiro Iwamoto, Halina Kobalava, Jacob Joseph Lamb e Trygve Magne Eikevik. "Optimizing Low-Temperature Three-Circuit Evaporative Cooling System for an Electric Motor by Using Refrigerants". Energies 17, n.º 16 (9 de agosto de 2024): 3942. http://dx.doi.org/10.3390/en17163942.

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This article presents modeling results and a comprehensive analysis of evaporative cooling systems designed for electric motors using the refrigerants R744 (trans-critical), R134a, R600a, and R290. This study aims to determine the most suitable refrigerant for use in a cooling system, optimize the system design, and calculate the maximum achievable motor power while adhering to specified temperature constraints. The modeling was validated by an experimental setup, which had the cooling system’s configuration featuring three circuits for motor housing, stator, and rotor cooling, respectively. The modeling of an evaporative system was used to present the cooling efficiency under varying loads and external temperature conditions. Mathematical modeling encompasses complex algorithms to simulate heat transfer phenomena, accounting for fluid dynamics and refrigeration cycle dynamics. The analyses revealed trends in winding temperature, rotor temperature, air temperature inside the motor, heat transfer coefficient, coefficient of performance (COP), and motor power across different operating conditions while using different cooling refrigerants. The maximal heat transfer coefficients were calculated for all the refrigerants for winding temperatures in the range from 32 to 82 °C, while air temperature and rotor temperatures were between 42 and 105 °C and 76 and 185 °C, respectively. Lowering the evaporation temperature of the coolant to −35 °C resulted in a significant decrease in the winding temperature to 15 °C, air temperature to 38 °C, and maximum rotor temperature to 118 °C at a motor power of 90 kW. Refrigerant R744 emerged as a promising option, offering high heat transfer coefficients and achieving high motor power within temperature limits. At the same time, the COP was lower when compared with other working fluids because of the high ambient temperature on the gas cooler side.
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Kang, Yunxin, e Ling Xu. "First-order Bandgap Reference Source Design with High Power Supply Rejection Ratio". Journal of Physics: Conference Series 2405, n.º 1 (1 de dezembro de 2022): 012003. http://dx.doi.org/10.1088/1742-6596/2405/1/012003.

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Abstract In this paper, a first-order bandgap reference source with a high power supply rejection ratio (PSRR) is designed. To obtain a low-temperature coefficient, a first-order bandgap temperature coefficient compensation method is used by adjusting the resistor resistance of the positive and negative temperature coefficients, and the gate-source voltage of the current mirror transistor is kept constant to increase the PSRR value in the low-frequency band. A self-start circuit is added to make the circuit start up quickly out of the simple bias point. The simulation results show that the bandgap reference voltage source has a constant 1.25V reference voltage with a temperature coefficient of 8.55ppm/°C in the temperature range of -40 to 125°C. The circuit is simulated using Cadence software. The circuit can be applied to OLED constant current source circuits and power management circuits.
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Hossain, Md Al Amin, Md Abdul Malek Soner, Md Abdus Salam, Md Fazlul Huq e Md Shamsul Huda Sohel. "Measurement of Feedback Reactivity Effects of the Baec Triga Reactor". Journal of Bangladesh Academy of Sciences 42, n.º 2 (30 de dezembro de 2018): 183–90. http://dx.doi.org/10.3329/jbas.v42i2.40050.

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The aim of this study is to measure the feedback reactivity effects of the Bangladesh Atomic Energy Commission (BAEC) TRIGA Research Reactor (BTRR). Using digital instrumentation and control (I&C) system, feedback parameters such as reactivity coefficients of fuel, moderator and power effects are measured. At 300 kW reactor power, the obtained results for fuel temperature coefficient are 0.664 ꬿ/0c and 0.765 ꬿ/0c at C1 and D3 core positions respectively. The results for 100 kW to 400 kW reactor power show its increasing nature as the reactor power increases. The measured value of the moderator temperature coefficient is found to be 0.419 ꬿ/0c at 500 kW reactor power. The power coefficient of reactivity is measured for several power ranges from 50 kW to 2.5 MW and the average value is found to be 0.0757 ꬿ/kw. The measured values of the reactivity coefficients are found to be in a good agreement with the GA Safety Analysis Report (SAR) provided for BTRR. Journal of Bangladesh Academy of Sciences, Vol. 42, No. 2, 183-190, 2018
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Prijić, Z., Z. Pavlović, S. Ristić e N. Stojadinović. "Zero-temperature-coefficient (ZTC) biasing of power VDMOS transistors". Electronics Letters 29, n.º 5 (1993): 435. http://dx.doi.org/10.1049/el:19930291.

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Imhoff, Eugene A., Karl D. Hobart, Francis J. Kub, M. G. Ancona, Rachael L. Myers-Ward, N. Y. Garces, Virginia D. Wheeler, Luke O. Nyakiti, Charles R. Eddy e D. Kurt Gaskill. "Positive Temperature Coefficient SiC PiN Diodes". Materials Science Forum 717-720 (maio de 2012): 981–84. http://dx.doi.org/10.4028/www.scientific.net/msf.717-720.981.

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Integration of patterned ballast resistance into the anode of SiC PiNs is a solution to the dilemma of negative dVf /dT for such diodes. In fabricated 4H-SiC PiN diodes, we demonstrate a cross-over from negative to positive temperature coefficient for current densities as low as 80 A/cm2. Adjusting the percentage of the patterned anode area, the positive or neutral dVf /dT can be achieved over a wide current-density range without substantial penalty in the forward voltage drop. This characteristic is crucial for high-power SiC packages with ganged-parallel rectifier arrays.
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Lin, Jyun-Min, Ying-Chung Chen e Chi-Pi Lin. "Annealing Effect on the Thermoelectric Properties of Bi2Te3Thin Films Prepared by Thermal Evaporation Method". Journal of Nanomaterials 2013 (2013): 1–6. http://dx.doi.org/10.1155/2013/201017.

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Bismuth telluride-based compounds are known to be the best thermoelectric materials within room temperature region, which exhibit potential applications in cooler or power generation. In this paper, thermal evaporation processes were adopted to fabricate the n-type Bi2Te3thin films on SiO2/Si substrates. The influence of thermal annealing on the microstructures and thermoelectric properties of Bi2Te3thin films was investigated in temperature range 100–250°C. The crystalline structures and morphologies were characterized by X-ray diffraction and field emission scanning electron microscope analyses. The Seebeck coefficients, electrical conductivity, and power factor were measured at room temperature. The experimental results showed that both the Seebeck coefficient and power factor were enhanced as the annealing temperature increased. When the annealing temperature increased to 250°C for 30 min, the Seebeck coefficient and power factor of n-type Bi2Te3-based thin films were found to be about −132.02 μV/K and 6.05 μW/cm·K2, respectively.
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Huang, Pei, Tong Shen, Zhenxing Liu, Renjun Dian, Wanlun Xu e Dan Wang. "Thermal characteristics analysis of medium frequency transformer under multiple working conditions". Thermal Science, n.º 00 (2023): 239. http://dx.doi.org/10.2298/tsci230807239h.

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Medium frequency transformer (MFT) plays an important role in high power AC-DC transformation in power grid, due to its high power density and high loss density, it brings difficulty to heat dissipation. Thermal reliability is crucial for transformer design, different from the previous work, the thermal characteristics of MFT under different working conditions are concerned and analyzed in this paper. The temperature field model of MFT is established, and the temperature field characteristics of MFT at rated load, no load, overload, fluctuating overload and short circuit conditions are simulated and analyzed, the results show that with the increase of load coefficient, the winding temperature increases obviously, the allowable load coefficient of MFT can be determined by calculating the transformer temperature at different load coefficients, which lays a foundation for thermal reliability and safe operation of MFT.
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Teses / dissertações sobre o assunto "Power temperature coefficient"

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Sandu, Sebastian. "Developing a power dissipation model for planetary roller screws". Thesis, Lyon, 2018. http://www.theses.fr/2018LYSEI096.

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Les vis à rouleaux convertissent la rotation en translation de manière très efficace et sont utilisées dans des nombreuses industries. Mais même s'il présente beaucoup d'avantages, le mécanisme reste complexe et relativement difficile à comprendre. Le principal but de cette thèse est de quantifier la puissance dissipée par les vis à rouleaux standard et inversées, qui est un résultat important pour toute étude liée à l'efficacité ou la distribution de température. De plus, il s'agit d'un critère de conception dans le choix de paramètres optimaux pour une certaine application. À cause des travaux peu nombreux en termes de recherche et des hypothèses restrictives faites dans la littérature courante, ce mémoire commence avec une analyse géométrique de base du mécanisme et envisage de généraliser les équations des surfaces filetées pour les différents types de profils et conditions de jeu. La position des points de contact peut ensuite être déduite avec un algorithme de type Newton-Raphson très rapide. Cette information est cruciale pour toute étude ultérieure de force. Après, les équations classiques de Hertz sont adaptées à des contacts peu conformes pour déterminer la forme, les dimensions et l'orientation des ellipses de contact rouleau-vis et rouleau-douille. Il est prouvé que les directions principales de courbure obtenues ici par géométrie différentielle sont différentes de celles supposées dans les précédents travaux de recherche. Ensuite, la cinématique du mécanisme est étudiée avec un modèle stationnaire, qui établit des liens entre les mouvements uniformes de tous les composants et permet de calculer d'une manière simplifiée le champ de vitesse de glissement en tout point de l'aire de contact. Le mouvement local apparaît comme une combinaison de spin et de glissement uniforme. Le modèle est calibré sur un seul degré de liberté qui prend la forme d'un quotient de glissement, qui dépend de conditions de lubrification et équations d'équilibre dynamique. Un banc expérimental est conçu pour mesurer ce quotient et permettre donc la comparaison avec des valeurs numériques, ainsi que les quelques modèles analytiques disponibles dans la littérature. Les résultats montrent que les mesures sont très proches des conditions de fonctionnement idéales, ce qui fait que les propriétés du lubrifiant et les coefficients de frottement deviennent les paramètres les plus influents dans le peu de marge disponible pour l'amélioration cinématique. Finalement, un modèle numérique en forces est développé et permet de calculer la puissance dissipée pendant l'équilibre stationnaire. L'algorithme itératif détermine d'abord le quotient de glissement atteint à l'équilibre et utilise ensuite le résultat pour déduire les autres variables cinématiques et dynamiques liées au calcul. Une étude paramétrique est réalisée dans le but d'identifier les facteurs importants pour l'efficacité et la puissance dissipée, ainsi que leur contribution relative
Roller screws are highly efficient rotation-translation converters used in a variety of industries. Despite its numerous advantages, the mechanism remains complex and rather difficult to understand. The main goal of this thesis is to quantify the amount of power dissipated by standard and inverted roller screws, which is an important result for any study related to efficiency or temperature distribution. Furthermore, it is used as a design criterion in choosing optimal parameters for a given application. Due to the limited amount of available research and the restrictive assumptions made in current literature, this memoir starts with a basic geometric analysis of the mechanism and attempts to generalize threaded surface equations for different types of profiles and backlash conditions. The contact point locations can then be deduced using a very fast Newton-Raphson algorithm. This information is crucial for any subsequent force analysis. Classic Hertzian equations are then adapted to slightly conforming contacts in order to calculate the shape, size and orientation of the roller-screw and roller-nut contact ellipses. It is shown that the principal directions of curvature obtained here by differential geometry are different from the ones assumed by previous research. Next, the mechanism kinematics is investigated using a stationary model, which relates the steady-state movement of all the different components and allows a simplified calculation of the sliding velocity field at any point within the contact areas. The local motion proves to be a combination of spin and uniform sliding. The model is set to have only one degree of freedom in the form of a slip ratio, which depends on lubrication conditions and force balance equations. An experimental setup is designed to measure this ratio and thus allow comparison to numerical values, as well as the few analytical models available in the literature. Results show that measurements are very close to ideal operating conditions, which makes lubricant properties and friction coefficients the most influential parameters in the little room available for kinematic improvement. Finally, a numerical force model is developed, which calculates the power dissipated during the steady-state regime. The iterative algorithm first determines the value of the slip ratio reached during stationary equilibrium and then uses the result to deduce the other kinematic and dynamic unknowns involved. A parametric study is conducted to identify the important factors in efficiency and power dissipation, as well as their relative influence
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Joseph, Jyothis. "Improving Photovoltaic Panel Efficiency by Cooling Water Circulation". Thesis, University of North Texas, 2018. https://digital.library.unt.edu/ark:/67531/metadc1404617/.

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This thesis aims to increase photovoltaic (PV) panel power efficiency by employing a cooling system based on water circulation, which represents an improved version of water flow based active cooling systems. Theoretical calculations involved finding the heat produced by the PV panel and the circulation water flow required to remove this heat. A data logger and a cooling system for a test panel of 20W was designed and employed to study the relationship between the PV panel surface temperature and its output power. This logging and cooling system includes an Arduino microcontroller extended with a data logging shield, temperature sensing probes, current sensors, and a DC water pump. Real-time measurements were logged every minute for one or two day periods under various irradiance and air temperature conditions. For these experiments, a load resistance was chosen to operate the test panel at its maximum power point. Results indicate that the cooling system can yield an improvement of 10% in power production. Based on the observations from the test panel experiments, a cooling system was devised for a PV panel array of 640 W equipped with a commercial charge controller. The test data logger was repurposed for this larger system. An identical PV array was left uncooled and monitored simultaneously to compare the effect of cooling, demonstrating that the cooled array provided up to an extra 132W or 20% of maximum power for sunny weather conditions. Future expansion possibilities of the project include automated water level monitoring system and water filtration systems.
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Ghorbani, Shaban Reza. "Structural and Electrical Transport Properties of Doped Nd-123 Superconductors". Doctoral thesis, KTH, Physics, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3461.

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It is generally believed that one of the key parameterscontrolling the normal state and superconducting properties ofhigh temperature superconductors is the charge carrierconcentrationpin the CuO2planes.By changing the non-isovalent dopingconcentration on the RE site as well as the oxygen content in(RE)Ba2Cu3O7−δ, an excellent tool is obtained tovary the hole concentration over a wide range from theunderdoped up to the overdoped regime.In the present thesis thefocus is on the doping effects on the structural and normalstate electrical properties in Nd-123 doped with Ca, La, Pr,Ca-Pr, and Ca-Th.T he effects of doping have been investigatedby X-ray and neutron powder diffraction, and by measurements ofthe resistivity, thermoelectric powerS, and Hall coefficient RH.T he thermoelectric power is a powerful tool forstudies of high temperature superconductivity and is highlysensitive to details of the electronic band structure.Sas a function of temperature has been analyzed in twodifferent two band models.The parameters of these models arerelated to charactristic features of the electron bands and asemiempirical physical description of the doping dependence ofSis obtained.So me important results are following:

(i)The valence of Pr in the RE-123 family.Results from thestructural investigations, the critical temperature Tc, and thethermoelectric power indicated a valence +4 at low dopingconcentration, which is in agreement with results of chargeneutral doping in the RE-123 family.(ii)Hole localization. The results of bond valence sum (BVS)calculations from neutron diffraction data showed that holelocalization on the Pr+4site was the main reason for the decrease of thehole concentration p.Differ ent types of localization wereinferred by S measurements for Ca-Th and Ca-Pr dopings.(iii)Competition between added charge and disorder. Theresults of RH measurements indicated that Ca doping introduceddisorder in the CuO2planes in addition to added charge.This could bethe main reason for the observed small decrease of thebandwidth of the density of states in the description of aphenomenological narrow band model.(iv) Empirical parabolic relation between γ and p.S data were analyzed and well described by a two-band modelwith an additional linear T term, γT.An empiricalparabolic relation for γ as a function of holeconcentration has been found.

Key words:high temperature superconductors, criticaltemperature, resistivity, thermoelectric power, Hallcoefficient, X-ray diffraction, Neutron diffraction, NdBa2Cu3O7−δ, hole concentration,substitution.

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Mirmasoudi, Sara. "High Temperature Transient Creep Analysis of Metals". Wright State University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=wright1452693927.

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Altalidi, Sulaiman Saleh. "Two-Phase Spray Cooling with HFC-134a and HFO-1234yf for Thermal Management of Automotive Power Electronics using Practical Enhanced Surfaces". Thesis, University of North Texas, 2017. https://digital.library.unt.edu/ark:/67531/metadc1011876/.

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The objective of this research was to investigate the performance of two-phase spray cooling with HFC-134a and HFO-1234yf refrigerants using practical enhanced heat transfer surfaces. Results of the study were expected to provide a quantitative spray cooling performance comparison with working fluids representing the current and next-generation mobile air conditioning refrigerants, and demonstrate the feasibility of this approach as an alternative active cooling technology for the thermal management of high heat flux power electronics (i.e., IGBTs) in electric-drive vehicles. Potential benefits of two-phase spray cooling include achieving more efficient and reliable operation, as well as compact and lightweight system design that would lead to cost reduction. The experimental work involved testing of four different enhanced boiling surfaces in comparison to a plain reference surface, using a commercial pressure-atomizing spray nozzle at a range of liquid flow rates for each refrigerant to determine the spray cooling performance with respect to heat transfer coefficient (HTC) and critical heat flux (CHF). The heater surfaces were prepared using dual-stage electroplating, brush coating, sanding, and particle blasting, all featuring "practical" room temperature processes that do not require specialized equipment. Based on the obtained results, HFC-134a provided a better heat transfer performance through higher HTC and CHF values compared to HFO-1234yf at all tested surfaces and flow rates. While majority of the tested surfaces provided comparable HTC and modestly higher CHF values compared to the reference surface, one of the enhanced surfaces offered significant heat transfer enhancement.
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Torres, aguilar Moira. "Development of photovoltaic module outdoor performance indicators based on experimental platforms". Electronic Thesis or Diss., Institut polytechnique de Paris, 2024. http://www.theses.fr/2024IPPAX025.

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Pour accélérer la transition énergétique vers le solaire photovoltaïque (PV) il faut améliorer la précision des estimations de puissance des installations solaires, la motivation principale de cette thèse. L'évaluation d'un module se fait dans des Conditions de Test Standard (STC) (irradiation de 1000 W/m², température du module (Tmod) de 25 °C, masse d'air de 1,5) que en général on ne trouve pas à l'extérieur, d'où la nécessité d'étudier le comportement d'un module PV fonctionnant dans des conditions réelles.Ce travail fournit une étude de cas de l'impact des facteurs comme l'irradiation (G), Tmod, la neige, le vent, l'ombrage et la salissure sur la production d'énergie d'un banc d'essai PV extérieur (BE) et d'une installation PV en toiture connectée au réseau (IT), situés sur le campus de l'École Polytechnique près de Paris. Basé sur cette analyse, différents filtres sont proposés pour nettoyer la base de données pour l'évaluation des performances. Le BE est composé de modules de cinq technologies différentes (a-Si/µc-Si, c-Si, CIS, HIT, CdTe). L'IT a une capacité de 16,3 kWp avec 52 panneaux de 6 modèles différents (feuille blanche et noire, PERC plein et demi-cellules, Q.ANTUM demi-cellules, bifacial), basés sur du silicium monocristallin.La caractérisation des performances de ces installations est effectuée sur une période de 4 ans pour le BE et de 3,5 ans pour l’IT. Pour le faire, on utilise des indicateurs de performance comme le rendement de référence, des modules et le ratio de performance (PR), avec leurs corrections de température.Les valeurs mensuelles du PR montrent des variations saisonnières selon le type de module, certaines d'entre elles montrant une forte dégradation au fil du temps. En moyenne, il y a une perte de PR du 5% due à l'effet de la température pour les modules à base de c-Si et d'environ la moitié pour ceux à couche mince dans le BE. Le PR moyen pendant l'hiver, compte tenu de l'effet de la température, est compris entre 89 et 93 % pour les modules c-Si et HIT et entre 77 et 90 % pour ceux à couches minces. En plus, des pertes de PR ont été observées dans l’IT dues à l'ombrage de 10 % pour la feuille noire, de 15 % pour celle blanche, de moins de 5 % pour les demi-cellules et de 7 % pour le bifacial.Un taux de dégradation a été estimé en %/an de -0,12, -0,30, -0,8, -0,46, -1,88 pour a-Si/µc-Si, c-Si, CIS, HIT, CdTe respectivement et de 1 %/an pour l’IT.La dernière analyse consiste à récupérer expérimentalement le coefficient de température de puissance (γ), utilisé pour corriger les estimations de puissance PV. Sa valeur STC (γSTC) est supposé constant et généralement prise de la fiche technique du module. Ce travail étudie sa dépendance à G (γG) et analyse la possibilité de l'utiliser pour améliorer la précision d’un modèle d'estimation de la puissance PV. Ceci est fait pour différentes données de G (pyranomètre, photodiode, extraites des mesures de courant de court-circuit, modélisées à partir de l'irradiance globale-directe-diffuse) et Tmod (mesurée, extraite des mesures de tension en circuit ouvert). Les résultats montrent que γ dépendait du niveau de G, des mesures d'irradiation utilisées pour son calcul et des filtres utilisés. L'utilisation de γG issu de pyranomètre ou d'irradiances modélisées et de Tmod mesuré n'améliore pas l'estimation de la puissance pour les modules du BE. En revanche, l'utilisation de mesures par photodiode réduit l'erreur relative moyenne absolue (rMAE) jusqu'à 2,9%, la rendant plus adéquate pour les technologies c-Si. De plus, le calcul de γG à partir de G et Tmod estimés via les mesures de la courbe I-V du module diminue la rMAE jusqu'à 3,6%. Cette méthode est adéquate pour les technologies c-Si et utile pour compenser la dégradation des modules à couche mince. Cette méthodologie a abouti à une amélioration de 1% de l'estimation de la puissance totale du BE
A crucial factor in accelerating the energy transition towards solar photovoltaic (PV) is the improvement of accuracy in power estimations from solar installations, the main motivation of this PhD thesis. The rating of a module is done under Standard Test Conditions (STC) (irradiance of 1000 W/m², module temperature (Tmod) of 25 °C, Air Mass of 1.5) not usually found outdoors, making it necessary to study the behavior of a PV module operating under real-life conditions.This work starts by providing a case-study of the impact of environmental factors such as irradiance (G), Tmod, snow, wind, shading, and soiling on the power output of a PV outdoor testbench and a grid-connected rooftop PV power plant, both located on the campus of École Polytechnique near Paris. Based on this analysis, different filters are proposed to clean the dataset for performance evaluation. The testbench is comprised of modules of five different technologies (a-Si/µc-Si, c-Si, CIS, HIT, CdTe). The rooftop installation has a capacity of 16.3 kWp with 52 panels of 6 different models (white and black backsheet, PERC full and half-cells, Q.ANTUM half-cells, bifacial), all based on monocrystalline silicon.Then, the performance characterization of said installations is carried out, for a 4-year period for the outdoor testbench and a 3.5-year period for the rooftop installation. This is done by utilizing performance indicators like reference yield, module yield, and performance ratio (PR), along with their temperature-corrected counterparts. Monthly PR values show diverse seasonal variation depending on the module type, some of them showing a strong degradation over time.On average, there is a 5% PR loss due to temperature effect for the c-Si-based modules and about half for the thin-film modules in the testbench. The average PR during winter, considering the temperature effect, is between 89-93 % for c-Si and HIT and between 77-90 % for thin-films. During this time, losses in PR due to shading of 10 % for the black backsheet, 15 % for the white backsheet, less than 5 % for the half-cells, and 7% for the bifacial module were observed in the rooftop installation.The PR loss for the modules in the testbench led to an estimated degradation rate in %/year of -0.12, -0.30, -0.8, -0.46, -1.88 for a-Si/µc-Si, c-Si, CIS, HIT, CdTe respectively and of 1%/year for the rooftop installation.The final analysis is the experimental retrieval of the power temperature coefficient (γ), commonly used to perform temperature corrections on PV power estimations and assumed to be constant, its STC value (γSTC) is usually taken from the module’s datasheet. Thus, this work studies its dependence on G (γG) and analyzes the possibility of using γG in a PV power estimation model to improve its accuracy. This is done for different data sources of G (pyranometer, photodiode, retrieved from short-circuit current measurements, modelled from global-direct-diffuse irradiance) and Tmod (measured, retrieved from open-circuit voltage measurements). The results showed a dependence of γ on the level of G, the irradiance sensor providing the measurements utilized for its computation, and the filters used to clean the data. Using a γG calculated with pyranometer or modelled irradiances and a measured Tmod yielded no improvement on the power estimation for the testbench modules whereas one using photodiode measurements reduced the relative mean absolute error (rMAE) by up to 2.9 %, proving more adequate for c-Si technologies. Furthermore, computing γG using a G and Tmod estimated from the module’s I-V curve measurements resulted in a decrease of rMAE of up to 3.6%, a method proving to be adequate for c-Si technologies and useful in compensating for degradation in thin-film modules. However, the improvements were modest, a 1% betterment of the total power estimation for the testbench
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Філянін, Данило Володимирович. "Методи і засоби інформаційного забезпечення режимів електричних мереж в умовах низької якості електроенергії". Thesis, Національний технічний університет України "Київський політехнічний інститут імені Ігоря Сікорського", 2019. http://repository.kpi.kharkov.ua/handle/KhPI-Press/40949.

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Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.14.02 – електричні станції, мережі і системи – Національний технічний університет України "Київський політехнічний інститут імені Ігоря Сікорського", Київ, 2018. Дисертація присвячена науково-прикладній проблемі – пошуку винуватців гармонічних спотворень в електричних мережах та підвищенню якості електроенергії шляхом створення системи діагностики і контролю на базі АСКОЕ. Обґрунтовано використання технології розподілених вимірювань для пошуку винуватців спотворень. Розроблено модифікацію методу гармонічного аналізу для підвищення достовірності визначення джерел спотворення. На підставі результатів досліджень запропоновано методи розподілу компенсаційних виплат між елементами електричної мережі та абонентами, що споживають потужність вищих гармонік. Розроблено ряд рекомендацій щодо практичного застосування результатів дисертаційної роботи. Запропоновано метод непрямого контролю температури кабельних ліній.
Thesis for the PhD degree in technical sciences, Specialty 05.14.02 – power plants and electric power complexes. National technical university of Ukraine "Kyiv polytechnic institute", Kyiv, 2019. The thesis is oriented to the scientific and applied problem - harmonic distortion sources detection in distribution systems (DS), improving the electromagnetic compatibility of electrical equipment, increasing the reliability of electric power supply by creating a diagnostic and control system. The use of distributed measurements to distortions source detection is justified. A modification of the method of harmonic analysis is developed to increase the reliability of distortions sources detection. Based on the study’s results, methods for distributing compensation payments between DS`s subjects that consume harmonics power are proposed. A number of recommendations on the practical application of the results of the thesis work have been developed. A method for indirect monitoring of the temperature of cable lines is proposed.
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Філянін, Данило Володимирович. "Методи і засоби інформаційного забезпечення режимів електричних мереж в умовах низької якості електроенергії". Thesis, Національний технічний університет "Харківський політехнічний інститут", 2019. http://repository.kpi.kharkov.ua/handle/KhPI-Press/40946.

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Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.14.02 – електричні станції, мережі і системи – Національний технічний університет України "Київський політехнічний інститут імені Ігоря Сікорського", Київ, 2018. Дисертація присвячена науково-прикладній проблемі – пошуку винуватців гармонічних спотворень в електричних мережах та підвищенню якості електроенергії шляхом створення системи діагностики і контролю на базі АСКОЕ. Обґрунтовано використання технології розподілених вимірювань для пошуку винуватців спотворень. Розроблено модифікацію методу гармонічного аналізу для підвищення достовірності визначення джерел спотворення. На підставі результатів досліджень запропоновано методи розподілу компенсаційних виплат між елементами електричної мережі та абонентами, що споживають потужність вищих гармонік. Розроблено ряд рекомендацій щодо практичного застосування результатів дисертаційної роботи. Запропоновано метод непрямого контролю температури кабельних ліній.
Thesis for the PhD degree in technical sciences, Specialty 05.14.02 – power plants and electric power complexes. National technical university of Ukraine "Kyiv polytechnic institute", Kyiv, 2019. The thesis is oriented to the scientific and applied problem - harmonic distortion sources detection in distribution systems (DS), improving the electromagnetic compatibility of electrical equipment, increasing the reliability of electric power supply by creating a diagnostic and control system. The use of distributed measurements to distortions source detection is justified. A modification of the method of harmonic analysis is developed to increase the reliability of distortions sources detection. Based on the study’s results, methods for distributing compensation payments between DS`s subjects that consume harmonics power are proposed. A number of recommendations on the practical application of the results of the thesis work have been developed. A method for indirect monitoring of the temperature of cable lines is proposed.
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Záboj, Jakub. "Návrh vytápění a ohřevu teplé vody v rodinném domě". Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2011. http://www.nusl.cz/ntk/nusl-229674.

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The thesis aims to propose a system for heating and hot water for a family house, according to drawings supplied by the building architect. At the request of the investor as the primary object will be considered a variant of underfloor heating. For comparing the heat loss, economic and possibly to State subsidies system selected will be processed by an alternative option to the ventilation air heating. Underfloor heating and hot air are among the low-temperature heating system, which can use low temperature heat sources, such as heat pumps. This assumption corresponds to investor requests, the source of heat in a family house with a heat pump and gas boiler. For hot water will be used as an alternative to a fireplace in the living room. To use the results of the thesis is to calculate the heat loss and heat, according to current standards include design and hot-water heating system including hot-drawing documentation. Finally, the economic evaluation of different alternatives in terms of investment and operating costs.
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Saulich, Sven. "Generic design and investigation of solar cooling systems". Thesis, Loughborough University, 2013. https://dspace.lboro.ac.uk/2134/13627.

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This thesis presents work on a holistic approach for improving the overall design of solar cooling systems driven by solar thermal collectors. Newly developed methods for thermodynamic optimization of hydraulics and control were used to redesign an existing pilot plant. Measurements taken from the newly developed system show an 81% increase of the Solar Cooling Efficiency (SCEth) factor compared to the original pilot system. In addition to the improvements in system design, new efficiency factors for benchmarking solar cooling systems are presented. The Solar Supply Efficiency (SSEth) factor provides a means of quantifying the quality of solar thermal charging systems relative to the usable heat to drive the sorption process. The product of the SSEth with the already established COPth of the chiller, leads to the SCEth factor which, for the first time, provides a clear and concise benchmarking method for the overall design of solar cooling systems. Furthermore, the definition of a coefficient of performance, including irreversibilities from energy conversion (COPcon), enables a direct comparison of compression and sorption chiller technology. This new performance metric is applicable to all low-temperature heat-supply machines for direct comparison of different types or technologies. The achieved findings of this work led to an optimized generic design for solar cooling systems, which was successfully transferred to the market.
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Capítulos de livros sobre o assunto "Power temperature coefficient"

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Shang, Chao-hao, You-sen Hu, Yuan-xiong Guo, Chang-ying Li e Jun Chen. "The Main Reason of SG Thermal Power Imbalance Between Each Loop in CPR1000 Nuclear Power Plants". In Springer Proceedings in Physics, 231–42. Singapore: Springer Nature Singapore, 2023. http://dx.doi.org/10.1007/978-981-99-1023-6_22.

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AbstractThe SG thermal power imbalance between each loop exists in some CPR1000 nuclear power plants. In this paper, the authors trying to figure out the chief reasons of SG power imbalance between each loop by analyzing the measurement data from the Nuclear Power Plants. The main thermal parameters from the nuclear power plants are analyzed. By analyzing factors affecting the SG thermal power, the main factors affecting the SG thermal power are loop flowrate and hot leg temperature. The loop flowrate depends on the pump characteristic curve and the loop resistance coefficient. The hot leg temperature depends on RPV structure and core power distribution. A CPR1000 SG model was established and the sensitivity analysis of the coefficients which affect SG heat transfer is performed. The analysis results show that the deviation of the hot leg temperature between loops has the most significant effect on the SG thermal power imbalance. Hence, the SG thermal power imbalance between each loop mainly due to the RPV structure, the core power distribution and the flowrate deviation.
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Demazière, C., e I. Pázsit. "On-line Determination of the MTC (Moderator Temperature Coefficient) by Neutron Noise and Gamma-Thermometer Signals". In Power Systems, 135–56. Berlin, Heidelberg: Springer Berlin Heidelberg, 2002. http://dx.doi.org/10.1007/978-3-662-04945-7_10.

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Huang, Yuxuan, Ruihuang Wu, Bingjun Xiong, Zhipeng Li, Jia Liu, Yun Zou, Jingjing Liu e Xinghua Sun. "An Ultra-Low Power CMOS Subthreshold Voltage Reference with Temperature Coefficient Compensation". In Lecture Notes in Electrical Engineering, 187–97. Singapore: Springer Nature Singapore, 2024. http://dx.doi.org/10.1007/978-981-97-2636-3_15.

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Liu, Ze, Sichuan Xu e Baitao Zhang. "Development and Validation of a 100 kW-Class Fuel Cell System Controller for Passenger Cars". In Proceedings of the 10th Hydrogen Technology Convention, Volume 1, 69–75. Singapore: Springer Nature Singapore, 2024. http://dx.doi.org/10.1007/978-981-99-8631-6_7.

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AbstractFuel cell (FC) vehicle is an important technology route to achieve carbon neutrality in transportation. This paper examines the integration, system control, and performance test of a high-power self-humidifying fuel cell system for passenger cars. Firstly, a high specific power FC system integration scheme is designed, and a highly integrated 100 kW self-humidifying fuel cell system is realized based on the installation requirements of passenger cars. Then, the system controller application layer is developed using Matlab/Simulink and the controller rapid development prototype for complete closed-loop control of each subsystem, such as hydrogen supply, air supply, cooling, and electrical management. Finally, the performance dynamics experiment of the 100 kW FC system is conducted based on the developed system controller. The results show that the developed system controller provides high-quality control effects of operating parameters such as air flow and pressure, hydrogen supply pressure, and cooling water temperature for the stack to meet different operating requirements. The highest efficiency of the system reaches 62%, and the coefficient of variation (Cv) of the cell voltages is controlled to be less than 1%. This study contribute to accelerate the deployment and application of high-power FC systems in passenger cars.
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Mukherjee, Koyel, Soumya Pandit e Rajat Kumar Pal. "Further Improved 198 nW Ultra-Low Power 1.25 nA Current Reference Circuit with an Extremely Low Line Sensitivity (0.0005%/V) and 160 ppm/$$^\circ $$C Temperature Coefficient". In Lecture Notes in Networks and Systems, 357–67. Singapore: Springer Nature Singapore, 2023. http://dx.doi.org/10.1007/978-981-99-2680-0_31.

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Zerrouk, I., S. G. Ionov, V. P. Popov e S. Hamamda. "Anisotropy of Thermal Expansion Coefficient of Pressed Graphite Foam Measured over the Temperature Interval 20-500°C". In Progress in Powder Metallurgy, 241–44. Stafa: Trans Tech Publications Ltd., 2007. http://dx.doi.org/10.4028/0-87849-419-7.241.

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Abdurakhmanov, Gulmurza, Dibya Prakash Rai e Gulbahor Vokhidova. "Modern Physics of the Thermoelectric Phenomena: Achievements and Problems". In New Materials and Devices for Thermoelectric Power Generation [Working Title]. IntechOpen, 2023. http://dx.doi.org/10.5772/intechopen.1002721.

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This chapter discusses internal discrepancies of contemporary conceptions of physics of thermoelectric phenomena (Seebeck, Peltier, and Thomson effects). These conceptions contradict also with experimental data obtained in a wide range of temperature for various materials (pure metals, alloys, Si, Ge, intermetallic and oxide compounds, borides, and silicides). One of these contradictions arises from the energy conservation law and definition of the Seebeck coefficient—the last cannot exceed 86.25 μV/K in any material. This limitation is met in metals and alloys, while in nonmetallic materials it exceeded hundreds and thousands of times. Experimental temperature dependence of the Seebeck coefficient demonstrates the polarity reversal and sharp extrema (increases up to 100–1000 times) for various materials, which are not followed from theory. Constancy of the Seebeck and Peltier coefficients (underlying the definitions of thermoEMF and Peltier heat) contradicts with Thomson formulae requiring temperature dependence of these coefficients (otherwise the Thomson effect is absent in any materials). The role of structural (spatial) inhomogeneity of the thermoelectric material and the wave nature of thermal radiation are discussed for potential physical mechanism of thermoEMF generation. Extension of expressions for charge and thermal energy flow to take into account nonlinear properties leads to huge mathematical complications.
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"Construction and Operating Parameters of Adsorptive Chillers". In Technology Development for Adsorptive Heat Energy Converters, 251–89. IGI Global, 2021. http://dx.doi.org/10.4018/978-1-7998-4432-7.ch008.

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The chapter is devoted to the design and performance of adsorptive chillers. Basic types of design and operating principle of adsorptive chillers were analyzed. Advantages and disadvantages performance of one-, two-, three-, and four-bed solar power adsorptive chillers are compared. Performance of adsorptive refrigerators based on composite adsorbents was studied. The correlation between the adsorbent composition and the coefficient of energy performance of the adsorptive chiler was revealed. An optimal composition of adsorbent 'silica gel – sodium sulphate' is stated to be of 20% silica gel and 80% sodium sulphate. The maximal values of the coefficient of performance of cycle of studied solar adsorptive chiller about of 1.14 are stated for composites containing about 20 wt. % silica gel and 80 wt% sodium sulphate. As a consequence of decreasing of adsorbent mass, the coefficient of performance is shown to increase when sodium sulphate content in the composite increased. Regeneration process parameters of the composite were shown to strongly affect on the coefficient of performance of the adsorptive chiller. The growth of the coefficient of performance is stated to result from decreasing the difference between adsorbent temperature and regeneration temperature from 85 to 55°C. The basic factors affecting the net coefficient of energy performance of the adsorptive solar refrigerator were stated daily solar radiant flux alongside with composition of the adsorbent and difference between adsorbent temperature and temperature regeneration. Net coefficients of performance of solar adsorptive refrigerator based on composite ‘silica gel – sodium sulphate' were stated to change from 0.25 to 0.34 during operating period. Utilization of the adsorption heat is suggested to warm the heat carrier which applied to heat adsorbent during regeneration. The ways to improve the design and performance of adsorptive solar chillers are suggested. The first one involves the introduction of solar collectors made of cellular polycarbonate plastics in the design of adsorptive solar chiller. Instantaneous efficiency coefficient were calculated as special thermal performance-solar radiant flux surface density ratio, optical efficiency factor is determined as special thermal performance-solar radiant flux surface density ratio at the equal temperatures of heat transfer medium and environment, reduced heat loss factor being calculated as the product of solar collector efficiency factor and net heat loss coefficient. The environmental test of developed collectors PSK-AV2-3, PSK-AV1-2, PSK-AV2-1, PSK-VS1-2, PSK-VS2-2, PSK-VS2-3, PSK-ST10-PW were conducted. The correlation of their results with laboratory tests when the thermohydraulic stand applied is shown. Relative accuracy of laboratory and environment tests was shown to be not exceeding 5 – 7%. The optical efficiency factor and the coefficient of thermal losses of polymeric solar collectors were determined. On the basis of the dependencies of the efficiency of the solar collectors vs. the reduced temperature, optimal designs of the polymeric solar collectors for the adsorption chilling solar systems are determined to be depended on the temperature of the regeneration temperature of the sorbents. As the temperatures of the regeneration of composite adsorbent ranged from 50ºС to 60ºС, appliance of the collectors PSK-AV2-1, PSK-CT10-PW occur to be expedient, and PSK-AB2-3, PSK-VS2-3, PSK-AB1-2, PSK-VS2-2, and PSK-VS1-2 are revealed to be more efficient when regeneration temperatures increased over 80 ºС. Thermotechnical characteristics of designed polymeric solar collectors are shown to surpass conventional metal and vacuum collectors. The perspectives of polymeric solar collectors in the design of adsorptive chilling solar plants were shown. Another way to improve the performance of adsorptive solar chillers concerns with equipping it with a photosensitive element and an electric drive, which will allow changing the angle of slope of the adsorber to the horizon depending on the intensity of the solar radiation. The chapter can be useful for design the efficient adsorptive chilling plants.
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Hooton, Brian. "Reactor Operations and Control". In Understanding Nuclear Reactors, 69–80. Oxford University PressOxford, 2024. http://dx.doi.org/10.1093/oso/9780198902652.003.0007.

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Abstract This chapter mentions the first natural reactor at Oklo, Gabon. Investigating chain reactions in the first reactors, Fermi’s first reactor CP1, with problems getting pure graphite. The story of CP1 is given. The components of a nuclear station are explained, Pressure vessel, coolant pump, pressurizer, and steam generator. The use of boron in the coolant to control reactivity. It explains how a reactor works with coolant transfer by Cold Leg, Hot Leg, and Cross Over Leg. Methods to measure power, neutron detectors, nitrogen16 gamma detectors, and calorimetry are given. It explains how using the enthalpy of the steam gives the most accurate value for reactor power. The roles of the fuel temperature coefficient, the moderator temperature coefficient, and the void coefficient in reactor control are described. It explains how operators and the computerized reactor control system deal with day-to-day operations in the control room, following steam demand.
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Lock, G. S. H. "The Simple, Tubular Thermosyphon". In The Tubular Thermosyphon, 35–102. Oxford University PressOxford, 1992. http://dx.doi.org/10.1093/oso/9780198562474.003.0002.

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Abstract Newton’s law of cooling, in which the rate of cooling of a body is taken to be proportional to its temperature measured relative to that of the environment, is the first quantitative statement ever made about natural convection. Implicit within this law is the requirement that the heat transfer coefficient at the body surface be constant. Today, not only is it known that the heat transfer coefficient h is a function of the temperature difference θ, but it is also understood that the natural convective system established around the body is governed directly by this temperature difference. It is a commonplace observation that h∝ θn where n is a small positive fraction. Over a small temperature difference range this power law relation may be approximated by a constant.
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Trabalhos de conferências sobre o assunto "Power temperature coefficient"

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Loaiza, David, F. Eric Haskin, Albert C. Marshall, Mohamed S. El-Genk e Mark D. Hoover. "TOPAZ II Temperature Coefficient Analyses". In SPACE NUCLEAR POWER AND PROPULSION: Eleventh Symposium. AIP, 1994. http://dx.doi.org/10.1063/1.2950131.

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Kawauchi, Yuma, Kenji Akimoto, Akihiko Watanabe e Ichiro Omura. "DUT Temperature Coefficient and Power Cycles to Failure". In 2021 33rd International Symposium on Power Semiconductor Devices and ICs (ISPSD). IEEE, 2021. http://dx.doi.org/10.23919/ispsd50666.2021.9452298.

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Da-Eun Jeong, Jae-Sub Ko, Jin-Gook Lee, Hak-Gyun Jeong, Dae-Kyong Kim e Dong-Hwa Chung. "MPPT control of photovoltaic system with temperature coefficient". In 2012 IEEE Vehicle Power and Propulsion Conference (VPPC). IEEE, 2012. http://dx.doi.org/10.1109/vppc.2012.6422602.

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4

Ford, R., e M. Kahn. "Positive Temperature Coefficient Resistors as High Power Pulse Switches". In Sixth IEEE International Symposium on Applications of Ferroelectrics. IEEE, 1986. http://dx.doi.org/10.1109/isaf.1986.201230.

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5

Wu, Zhenxing, Yu Wu, Yunpeng Jia, Feifei Tian, Yin Liu e Yueyang Liu. "Research to Improve the Forward Temperature Coefficient of FRD". In 2010 Asia-Pacific Power and Energy Engineering Conference. IEEE, 2010. http://dx.doi.org/10.1109/appeec.2010.5448583.

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6

Ishii, R., H. Tsuchida, K. Nakayama e Y. Sugawara. "20V-400A SiC Zener Diodes with Excellent Temperature Coefficient". In 19th International Symposium on Power Semiconductor Devices and Ics. IEEE, 2007. http://dx.doi.org/10.1109/ispsd.2007.4294986.

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7

Mamaev, Boris I., e Mikhail M. Petukhovskiy. "Gas Temperature Profile Attenuation Through a Multistage Axial-Flow Turbine". In ASME Turbo Expo 2009: Power for Land, Sea, and Air. ASMEDC, 2009. http://dx.doi.org/10.1115/gt2009-59033.

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Resumo:
Nowadays 2D through-flow models are widespread for designing and analysis of a turbine. Unlike 2D calculations, the measurements show that a non-uniform inlet gas temperature profile is strongly attenuated to the outlet of a turbine. This attenuation can be taken into account in through-flow models only using some corrective coefficients. The objective of this work was to find such an empirical coefficient. The results of full-scale tests of several power GTUs and aviation GTEs were employed to obtain values of the temperature profile attenuation coefficient in the through-flow model for various span locations of airfoil rows. During the tests detailed radial-circumferential distributions of the gas temperature upstream of each of rows and downstream of the turbines were measured (in absolute motion for stator and in relative motion for rotor). The values of the attenuation coefficient for airfoil rows of the three front stages were obtained by means comparison of experimental and computed results. The experience shows that the attenuation coefficient is easily incorporated into the 2D gas-dynamic codes. This incorporation allows spanwise distributions of flow parameters to be predicted and the airfoil geometry and cooling mass flow to be chosen more correctly.
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"A Low Temperature Coefficient and Low Power Voltage Detector for Energy Harvesting". In 2021 IEEE International Symposium on Circuits and Systems (ISCAS). IEEE, 2021. http://dx.doi.org/10.1109/iscas51556.2021.9401120.

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9

Ning Li e Peng Jin. "Voltage-temperature coefficient analysis and testing of high power light-emitting diodes". In 2013 10th China International Forum on Solid State Lighting (ChinaSSL). IEEE, 2013. http://dx.doi.org/10.1109/sslchina.2013.7177333.

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10

Pakravan, Elaheh, Mortaza Mojarad e Behboud Mashoufi. "A Low-Power Bandgap Voltage Reference Circuit With Ultra-Low Temperature Coefficient". In 2023 5th Iranian International Conference on Microelectronics (IICM). IEEE, 2023. http://dx.doi.org/10.1109/iicm60532.2023.10443209.

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