Joule losses

As already mentioned, the induced current Ipl heats the plasma due to joule losses which are proportional to the plasma resistance. With increasing temperature the plasma resistance decreases and the ohmic heating becomes less effective. Theoretical analysis shows that the maximum temperature which can be reached in this way is below 2 keV, i.e. the plasma cannot enter the ignition region of 5 keV4. Therefore,... 

One of the problems caused by the liner is substantial energy loss on its surface, since the L/R time constant of the thin liner is comparable to the plasma formation time constant. During the plasma formation, 85 kJ and 65 kJ are lost due to poloidal and toroidal liner currents, respectively. In the no-plasma mode or in the failure mode, the energy d imped on the liner is large. The joule loss in the plasma is expected to be 80 kJ with 0.5 eV starting electron temperature and classical resistivity. The final plasma has a stored magnetic energy of 50 kJ in both the poloidal and toroidal fields. 

PF System Resistance PF System Inductance Maximum Joule Loss 1/2LI ... 

It is instructive to show the advantage of low-beta operation,when the joule loss is taking place, after the plasmoid formation. In order to maintain the plasma temperature high, the energy decay time Tg is required to satisfy the condition ... 

Solid Oxide Fuel Cells, Thermodynamics, Fig. 3 Themodynamic theoretical conversion efficiency for reforming SOFC and further lowering in efficiency due to the Joule loss and electrochemical oxygen permeation through the YSZ electrolyte for difference thickness... 

The supercapacitor can be characterized by a capacitance in series with a resistance. The capacitance represents its ability to store electrical energy. The series resistance represents the Joule losses. These losses cause the component s temperature to rise. The increase in temperature of the supercapacitor can degrade its energy performances and accelerate its aging. 

In the case of supercapacitors, heat production is linked mainly to the Joule losses relating to the equivalent series resistance. Indeed, supercapacitor currents may be of the order of 400 A or more depending on the type and technology used, even if the series resistance is very low (less than 1 mfJ). This leads to a drastic increase in the temperature of the supercapacitor with repeated charge/discharge cycles. This heating may lead to the following consequences ... 

To model performance change of nonequilibrium devices due to Joule losses an approximate empirical relation is applicable stating that the detector temperature increase is linearly proportional to the dissipation power divided by the active electrical area of the detector. For a HgCdTe photoconductor the proportionality factor has an empirical value of 0.6 Km /W). When numerically calculating thermal... 

The length of each current line is increased by 2h, the resistance Rj=R-Rs is due to losses by joule effect in the ring volume of eddy currents of Ar deep. 

The diird curve, dial of die compression/Joule-Tliomson cooling, shows 58.2% efficiency. This is calculated based on die difference in die accounting shown in Table 3-2 and is die practical efficiency of diis effect. It would be 68%—that of die compressor—except for several losses, such as die warm end temperature difference and a small, not easily recoverable, portion of the flash loss. 

Corresponding to the charge in the potential of single electrodes which is related to their different overpotentials, a shift in the overall cell voltage is observed. Moreover, an increasing cell temperature can be noticed. Besides Joule-effect heat losses Wj, caused by voltage drops due to the internal resistance Rt (electrolyte, contact to the electrodes, etc.) of the cell, thermal losses WK (related to overpotentials) are the reason for this phenomenon. 

Jahn-Teller distortions 309 ff Japanese separators 264, 267 Joule effect, heat losses 13 jump frequency, solid electrolytes 532 Jungner nickel cadmium batteries 22... 

For collision frequencies large compared with the frequency of the electric field, the current remains in phase with the electric field in the reverse case, the current is 90° out of phase. The in-phase component of the current gives rise to an energy loss from the field (Joule heating loss) microscopically, this is seen to be due to the energy transferred from the electrons to the atoms upon collision. 

Micro reactors are seen to have smaller inhomogeneities of the electrical field and less temperature rise in the reaction medium due to the Joule heating effect between the electrodes [70]. Submillimeter interelectrode gaps are expected to reduce the ohmic loss. 

Capacitance measurements are quite simple. A typical drawback is the need of coaxial cables that introduce a thermal load which is not negligible in low-power refrigerators. On the other hand, capacitance bridges null the cable capacitance. Multiplexing is more difficult than for resistance thermometers. In principle, capacitors have low loss due to Joule heating. This is not always true losses can be important, especially at very low temperatures. Dielectric constant thermometers have a high sensitivity capacitance differences of the order of 10-19F can be measured. 

A process is thermodynamically reversible when an infinitesimal reversal in a driving force causes the process to reverse its direction. Since all actual processes occur at finite rates, they cannot proceed with strict thermodynamic reversibility and thus additional nonrevers-ible effects have to be regarded. In this case, under practical operation conditions, voltage losses at internal resistances in the cell (these kinetic effects are discussed below) lead to the irreversible heat production (so-called Joule heat) in addition to the thermodynamic reversible heat effect. 

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