Fluidic and Mechanical Thermal Control Devices

Abstract

In recent years, intensive studies on thermal control devices have been conducted for the thermal management of electronics and computers as well as for applications in energy conversion, chemistry, sensors, buildings, and outer space. Conventional cooling or heating techniques realized using traditional thermal resistors and capacitors cannot meet the thermal requirements of advanced systems. Therefore, new thermal control devices are being investigated to satisfy these requirements. These devices include thermal diodes, thermal switches, thermal regulators, and thermal transistors, all of which manage heat in a manner analogous to how electronic devices and circuits control electricity. To design or apply these novel devices as well as thermal control principles, this paper presents a systematic and comprehensive review of the state‐of‐the‐art of fluidic and mechanical thermal control devices that have already been implemented in various applications for different size scales and temperature ranges. Operation principles, working parameters, and limitations are discussed and the most important features for a particular device are identified.

Ferrofluidic thermal switch in a magnetocaloric device

“…Internal heat generation is a consequence of effects accompanying the actuation of the thermal switches that transform into heat and heats the thermal switch (Joule heating, eddy currents, friction, etc.). More about these issues can be found in the following references ( Klinar et al., 2021 ; Swoboda et al., 2021 ; Wehmeyer et al., 2017 ).…”

“…The first studies on thermal switches began in 1949, when Heer and Daunt (1949) investigated the change in the thermal resistance in superconducting and normal states for tin and tantalum at temperatures below 1 K. Since then, different mechanisms have been developed for applications operating at or above room temperature by implementing solid-state, fluidic, and mechanical thermal switches. These are described in a few recent review papers ( Klinar et al., 2021 ; Swoboda et al., 2021 ; Wehmeyer et al., 2017 ). The performance of the thermal switch is determined by the switching ratio (the ratio of heat fluxes in the on and off states), the switching time (the time it takes to transition from on to off , and vice-versa), and the energy efficiency.…”

Thermal rectification in multilayer phase change material structures for energy storage applications

“…In recent years, solid-state thermal control devices ( Swoboda et al., 2020 ) have received increased attention as a potential solution for improved energy management, storage, or conversion ( Klinar et al., 2020b ; Liu et al., 2019 ; Swoboda et al., 2020 ; Wong et al., 2021 ). Thermal diodes, regulators, switches, or transistors are capable of managing heat in a manner analogous to how electricity is controlled by their electrical counterparts ( Wehmeyer et al., 2017 ).…”

Caloric devices: A review on numerical modeling and optimization strategies

“…This way, one can avoid to use complex hydraulic systems, which can result in cheaper and more reliable devices. These systems substitute the use of fluids by thermal management elements (TMEs): heat switches, heat diodes, or heat regulators 41,54 . These components are usually located between the CM and the HEXs.…”