Effect Ettingshausen

Equation (6.10.4b) shows that a current flow along x produces a temperature gradient along y this is the so-called Ettingshausen effect, specified by... 

The purpose of this paper is to review recent progress that has been made in this laboratory toward application of the Ettingshausen effect to thermomagnetic cooling devices. The material requirements based upon transport theory and the device theory will be outlined, and a comparison of theory with the performance of an actual cooling device will be made. 

As previously stated, the Ettingshausen effect occurs when a current is made to flow in a conductor perpendicular to a magnetic field (Fig. la). The Ettingshausen coefficient which defines this effect is... 

The Hall effect, first reported in 1879 by Hall, is by far the best known of the various galvanothermomagnetic effects. In this case, if an electrical current is made to flow in a conductor perpendicular to a magnetic field, in addition to the transverse temperature gradient due to the Ettingshausen effect, one also observes a transverse electric field which is perpendicular to both the electrical current and the magnetic field (Fig. Ic). The Hall coefficient is defined by... 

The transverse temperature gradient we are trying to produce by the Ettingshausen effect will tend to be thermally shorted out through the electrodes. 

For the two-carrier system, the situation is considerably different. In this case, referring to Fig. 3b, thermal energy is transported by both holes and electrons and the Ettingshausen effect is mainly due to generation of hole-electron pairs at one side of the sample and their recombination on the other side. In addition, if the number densities and the mobilities of the holes and electrons are equal, the Hall effect and thus the opposing Hall field vanishes. In this case, the Ettingshausen effect is expected to be quite large. 

The Ettingshausen effect, which has historically been assumed to be very small, is in fact quite large in the bismuth-antimony alloy system at temperatures below 200°K. By utilizing this effect in a cooling device, practical solid-state cooling is now feasible in the... 

Magnetic Faraday effect Magnetostriction Ettingshausen effect Hall effect Magnetic induction ... 

PHENOMENOLOGICAL DESCRIPTION OF TRANSVERSE GALVANOTHERMO-MAGNETIC EFFECT AND ETTINGSHAUSEN COOLERS... 

Ettingshausen F, Kleemann J, Michel M, Quintus M, Fuessa H and Roth C (2009), Spatially resolved degradation effects in membrane-electrode-assembUes of vehicle age polymer electrolyte membrane fuel cell stacks. Journal of Power Sources, 194,899-907. 

---