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Electrocaloric effect

AS, entropy (C/T) AT, heat capacity C, divided by T Pi Et, electrocaloric effect q, Hi, magnetocaloric effect ay <3y, piezocaloric effect... [Pg.295]

Permittivity variations in a strong electric field non-linear and saturation behaviour progress of e gperimental methods molecular behaviour and various theoretical models molecular correlations complete dielectric saturation electrostriction and electrocaloric effect. [Pg.105]

On using the approximation (330a) this variation vanishes. Many authors use the following, approximate formula for the electrocaloric effect - ... [Pg.194]

Table 19 Aef(E) variations due to electrocaloric effect in dielectric samples of various shapes calculated with the data listed in ref. 4886... Table 19 Aef(E) variations due to electrocaloric effect in dielectric samples of various shapes calculated with the data listed in ref. 4886...
The pyroelectric effect is used in pyroelectric energy harvesting, and the electrocaloric effect is currently being explored for refrigeration. Perovskite aystals that show the pyroelectric effect contain a unique polar axis and a spontaneous electric polarisation, P, directed along this axis. As all ferroelectrics are also pyroelectrics (Chapter 6),... [Pg.288]

The inverse efFect-that is, the dependence of temperature on an external electric field (AT = q-E where q is the electrocaloric coefficient)-is used today in devices for electrostatic cooling to achieve temperatures close to the absolute temperature, as required for experiments conducted in the Large Hadron Collider. [Pg.291]

The above scheme actually involves 9 + 3+ 1 =13 distinct equations, each containing 13 independent variables. Proceeding across the various entries we find the following (1,1) elasticity, all (Trs except u / remain fixed (1,2) converse piezoelectricity (1,3) thermal expansion (2,1) direct piezoelectricity, all ffrs except ajk remain fixed (2,2) electrical permittivity (2,3) pyro-electrity (3,1) piezocaloric effect, all Urs except [Pg.324]

These Maxwell relations show that the matrix elements in Eq. (5.11.2) are symmetric about the diagonals. Specifically, the coefficients of the direct and converse piezoelectric effects are equal—a conclusion that verifies an earlier statement in Section 5.10. Also, the coefficients for the thermal expansion and for the piezocaloric, as well as for the pyroelectric and electrocaloric effects, respectively, are identical. Again, bear in mind that Eq. (5.11.2) represents six relations for e,-, three relations for Dj, and one equation for d5, each of which contains six variables Uy, three variables ,-, and Tas the independent quantities. [Pg.324]

Figure 1.32 The well-known triangle used to describe the pathways between mechanical, electrical, and thermal energies in a class of noncentrosymmetric materials exhibiting piezoelectric effect, pyroelectric effect (converse of electrocaloric effect), piezocaloric effect (converse ofthermal expansion), and so on. For... Figure 1.32 The well-known triangle used to describe the pathways between mechanical, electrical, and thermal energies in a class of noncentrosymmetric materials exhibiting piezoelectric effect, pyroelectric effect (converse of electrocaloric effect), piezocaloric effect (converse ofthermal expansion), and so on. For...
The electrocaloric properties of (Pb,La)(Zr,Ti)03 (PLZT) and BaTiOj ceramics were investigated by the indirect estimation and direct measurement of temperature-electric field (T-E) hysteresis loops. The measured T-E loops showed a similar shape to strain-electric field (s-E) loops. The adiabatic temperature change AT due to electrocaloric effects was estimated from the polarization change of these samples. ATs of 038 and 0.36 K were estimated for the (Pb,La)(Zr,Ti)03 (PLZT)(9.1/65/35) ceramics and BaTi03 ceramics sintered at 1400 Q respectively. The measured temperature changes ATs in these samples upon the release of the electric field from 30 kV/cm to zero were 0.26 and 0.29 K, respectively. [Pg.139]

Keywords Electrocaloric effect, PLZT, BaTiO refrigerator... [Pg.139]

Mischenko AS, Zhang Q, Scott JF, Whatmore RW and Mathur ND Giant electrocaloric effect in thin-film PbZro95Tioo503.Science, 2006 311 1270-1271. DOI 10.1126/ science.il23811... [Pg.149]

Shebanovs L, Borman K, Lawless WN, Kalvane A Electrocaloric effect in some per-ovskite ferroelectric ceramics and multilayer capacitor. Ferroelectr., 2002 273 137-142. DOI 10.1080/00150190211761... [Pg.149]

Mischenko AS, Zhang Q, Whatmore RW, Mathur ND Giant electrocaloric effect in the thin film relaxor ferroelectric O.OPbMgi/jNbj/sOs-O.lPbTiOs near room temperature. Appl. Phys. Lett, 2006 89 242912. DOI 10.1063/1.2405889... [Pg.149]

Chen H, Ren TL, Wu XM, Yang Y, Liu LT Giant electrocaloric effect in lead-free film of strontium bismuth tantalite. Appl. Phys. Lett, 2009 94 182902. DOI 10.1063/1.3123817... [Pg.149]

Neese B, Chu B, Lu SG, Wang Y, Furman E, Zhang QM Large electrocaloric effect in ferroelectric pol)nners near room temperature. Science, 2008 321 821-823. DOI 10.1126/science.ll59655... [Pg.149]

Lu SG, Rozic B, Zhang QM, Kutnjal Z, Pirc R, Lin M, Li X, Gomy L Comparison of directly and indirectly measured electrocaloric effect in relaxor ferroelectric polymer. Appl. Phys. Lett. 2010 97 202901. DOI 10.1063/1.3514255... [Pg.150]

Wang J, Yang T, Wei K, and Yao X Temperature-electric field hysteresis loop of electrocaloric effect in ferroelectridty—Direct measurement and analysis of electrocaloric effect. I. Appl. Phys. Lett. 2013 102 152907. DOI 10.1063/1.4801997... [Pg.150]

Heat evolved by applying an electric field (electrocaloric effect)... [Pg.518]

See other pages where Electrocaloric effect is mentioned: [Pg.198]    [Pg.198]    [Pg.192]    [Pg.196]    [Pg.395]    [Pg.396]    [Pg.421]    [Pg.422]    [Pg.423]    [Pg.200]    [Pg.288]    [Pg.289]    [Pg.302]    [Pg.174]    [Pg.14]    [Pg.75]    [Pg.179]    [Pg.254]    [Pg.504]    [Pg.1546]    [Pg.139]    [Pg.140]    [Pg.148]    [Pg.149]   
See also in sourсe #XX -- [ Pg.198 ]



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