Search results for "Electric heating"
showing 8 items of 8 documents
Environmental benefits through new distributed on site control actions inside European apartments
2008
Energy management control actions inside apartments and detached houses have to be carried out in order to reduce CO2 emissions. In this work, new control actions turned to the reduction of both electrical energy losses and electrical energy consumptions inside typical European (Italian, French, German and United Kingdom) apartments are proposed. These actions are of the ldquoLoad Shiftingrdquo type, that makes the apartment daily load profile as flat as possible, and of the ldquoDistributed on Site (DoS)rdquo type consisting in heating the water needed by dishwashers and washing machines inside instantaneous gas water heaters (IGWHs) instead of inside the household appliances themselves. T…
Modeling propagation in high-power microwave devices
1999
Efficient generation of energetic ions in multi-ion plasmas by radio-frequency heating
2017
We describe a new technique for the efficient generation of high-energy ions with electromagnetic ion cyclotron waves in multi-ion plasmas. The discussed ‘three-ion’ scenarios are especially suited for strong wave absorption by a very low number of resonant ions. To observe this effect, the plasma composition has to be properly adjusted, as prescribed by theory. We demonstrate the potential of the method on the world-largest plasma magnetic confinement device, JET (Joint European Torus, Culham, UK), and the high-magnetic-field tokamak Alcator C-Mod (Cambridge, USA). The obtained results demonstrate efficient acceleration of 3He ions to high energies in dedicated hydrogen–deuterium mixtures.…
Practical Application of Eddy Currents Generated by Wind
2011
When a conductive material is subjected to time-varying magnetic fluxes, eddy (Foucault) currents are generated in it and magnetic field of opposite polarity as the applied one arises. Due to the internal resistance of the conductive material, the eddy currents will be dissipated into heat (Joule heating). Conventional domestic water heaters utilize gas burners or electric resistance heating elements to heat the water in the tank and substantial part of the energy to use for it is wasted. In this paper the origin of electromagnetic induction heat generated by wind turbine in special heat exchange camera connected to water boiler is discussed and material evaluation performed using mathemati…
Hybrid simulation of electron cyclotron resonance heating
2008
Electron Cyclotron Resonance (ECR) heating is a fundamentally important aspect in understanding the physics of Electron Cyclotron Resonance Ion Sources (ECRIS). Absorption of the radio frequency (RF) microwave power by electron heating in the resonance zone depends on many parameters including frequency and electric field strength of the microwave, magnetic field structure and electron and ion density profiles. ECR absorption has been studied in the past by e.g. modelling electric field behaviour in the resonance zone and its near proximity. This paper introduces a new ECR heating code that implements damping of the microwave power in the vicinity of the resonance zone, utilizes electron de…
Dielectric Characterization of Fruit Nectars at Low RF Frequencies
2015
Dielectric properties of apple, apricot, peach, and pear nectars were studied in the frequency range from 15 kHz to 30 MHz and the temperature range from 25 to 60 degrees C. Both the relative dielectric constants and the dielectric loss factors decreased by increasing frequency and increased linearly with increasing temperature with values in the order 10(4)-10(2) and 10(5)-10(2), respectively. The power dissipation densities and the power penetration depths were found to increase linearly with temperature. Power dissipation densities remained essentially constant for all the samples while power penetration depths decreased significantly on increasing frequency. The dependence of each of th…
Nanocrystallization of amorphous alloys using microwaves:In situtime-resolved synchrotron radiation studies
2009
Important energy and time savings can be achieved with the thermal treatment of materials by replacing conventional heating methods with microwave heating. The nano- crystallization of Co-Fe-W-B amorphous alloy powders under microwave irradiation was followed for the first time by in situ time-resolved synchrotron radiation powder diffraction. It is shown that even a very short exposure to the electromagnetic field (single pulse microwave application) typically of the order of a few seconds is sufficient to obtain the bulk nano- crystalline state. A metastable high-temperature Co-W-B orthorhombic phase forms during the microwave heating, which gradually transforms to the tetragonal Co2B sta…
Microwave heating as a tool for coupling Marangoni and Hickman instabilities
2007
The aim of this paper is the linear stability analysis of an evaporating interface in order to justify hydrodynamic behaviors observed during evaporation of water and ethanol simultaneously under microwave irradiation and reduced pressure. In relation to the local character of the thermal conversion of electromagnetic energy, and of the thermal dependency of the dielectric loss, it seems possible under microwave heating to induce a specific hydrodynamic compared to those induced by conventional heating.