Dobovišek Andrej, Ambrožič Milan, Kutnjak Zdravko, Kralj Samo
University of Maribor, Koroška Cesta 160, 2000, Maribor, Slovenia.
University of Maribor, Taborska Ulica 8, 2000, Maribor, Slovenia.
Heliyon. 2023 Feb 24;9(3):e14035. doi: 10.1016/j.heliyon.2023.e14035. eCollection 2023 Mar.
The active electrocaloric (EC) regenerator exploiting electric conversion into thermal energy has recently become important for developing a new generation of heat-management devices. We analyze an active EC regenerator numerically. We establish a temperature span across the regenerator by commuting a liquid crystalline (LC) unit between regions with and without an external electric field . In modelling, we use Landau-de Gennes mesoscopic approach, focusing on the temperature regime where isotropic (paranematic) and nematic phase order compete. We determined conditions enabling a large enough value of suitable for potential applications. In particular, (i) the vicinity of the paranematic-nematic (P-N) phase transition, (ii) large enough latent heat of the transition, (iii) strong enough applied external field (exceeding the critical field at which the P-N transition becomes gradual), and (iv) relatively short contact times between LC unit and heat sink and heat source reservoirs are advantageous. Our analysis reveals that could be achieved using appropriate LC material.
利用电能向热能转换的有源电热（EC）蓄热器最近在新一代热管理设备的开发中变得至关重要。我们对有源EC蓄热器进行了数值分析。通过在有和没有外部电场的区域之间切换液晶（LC）单元，我们在蓄热器上建立了一个温度跨度。在建模中，我们使用朗道 - 德热内斯介观方法，重点关注各向同性（顺排相）和向列相序竞争的温度范围。我们确定了能够实现足够大的[具体物理量未明确，用 指代]值以适用于潜在应用的条件。特别是，（i）顺排相 - 向列相（P - N）相变附近，（ii）足够大的相变潜热，（iii）足够强的外部施加场（超过P - N相变变得渐进的临界场 ），以及（iv）LC单元与散热器和热源储器之间相对较短的接触时间是有利的。我们的分析表明，使用合适的LC材料可以实现[具体物理量未明确，用 指代]。
