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E-book Transformation Thermotics and Extended Theories : Inside and Outside Metamaterials

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Penilaian

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The first level (LV1) is those transformation-related theories for designing cloak-ing, concentrating, rotating, etc. Since the theory of transformation thermotics wasproposed for controlling steady and passive heat conduction in 2008 [1,2], extendedtransformation theories have been developed successively from steady and passiveto transient and active heat conduction [3]. Then, temperature-dependent (nonlin-ear) thermal conductivities were considered for developing nonlinear transformationthermotics [4]. These coordinate transformations were all time-independent, mak-ing it challenging to deal with time-dependent coordinate transformations. Thus,spatiotemporal coordinate transformations were discussed [5]. Beyond conduction,convection is also a primary heat transfer mode, so researchers developed a trans-formation theory for convection control [6]. Nevertheless, it was still challenging toguide convective velocities directly. Therefore, the Darcy law in porous media wasintroduced to transform convection and ensure feasibility [7,8]. Another convec-tive model with creeping flows was also explored [9]. The last basic heat transferscheme is radiation, and researchers also proposed a transformation theory to reg-ulate the radiation described by the Rosseland diffusion approximation [10]. Withthese efforts, conduction, convection, and radiation can be unified in the transformation framework [11]. Besides, heat transfer may also be accompanied by otherphysical processes, such as electric transport. Therefore, a transformation theory wasput forward to regulate thermal and electric fields simultaneously [12]. Researchersfurther studied the coupling between thermal and electric fields, i.e., the thermo-electric effect, and proposed a transformation theory [13]. Therefore, most thermalphenomena can be manipulated by transformation theories.The second level (LV2) is other theories for designing functions predicted bythe transformation theory. Although the transformation theory is powerful, it stillhas some limitations. For example, the parameters for thermal cloaking should beanisotropic, inhomogeneous, and even singular. Thus, other theories beyond thetransformation theory were proposed. We take thermal cloaking as an example. Abilayer scheme was proposed [14–16] to remove anisotropic and inhomogeneousparameters. Then, an active scheme was developed to remove all parametric require-ments because only active temperature control was required [17]. Furthermore, adipole-based scheme was considered to simplify the active temperature control [18].Besides these analytical theories, topology optimization is an indispensable methodthat largely simplifies the design [19,20]. These theories and schemes are distinctlydifferent from the transformation theory, but they are still applied to design functionspredicted by the transformation theory.The third level (LV3) is other theories for designing functions not predicted bythe transformation theory. With the development of theoretical thermotics, manyphenomena and functions beyond the predictions of transformation thermotics wererevealed, such as the anti-parity-time symmetry in diffusive systems [21,22], diffu-sive geometric phases [23,24], thermal wave nonreciprocity [25–29], thermal edgestates [30–34], and thermal skin effects [35,36]. These emerging theories may guidethe future development of theoretical thermotics.2.2 Characteristic LengthCompared with traditional thermodynamics (A in Fig.2.1), theoretical thermoticsfocuses on the active control of heat based on transformation thermotics and extendedtheories (B in Fig.2.1). Since theoretical thermotics also designs artificial structuresfor heat regulation, what is the relation between theoretical thermotics and the emerg-ing field of metamaterials? The answer is the characteristic length.Metamaterials generally refer to those artificial structures with a structural unitsize (much) smaller than the characteristic length (C in Fig.2.1). In this way, anartificial structure has novel parameters that do not exist in nature or chemical com-pounds according to effective media, such as negative permittivities. Electromagneticmetamaterials (C2 in Fig.2.1) originate from the research on negative refractiveindex [37–39]. Then, the metamaterial research was extended to other wave systems(C3inFig.2.1), such as acoustics [40,41] and elastodynamics [42,43]. In 2008,transformation thermotics and thermal cloaking were proposed [1,2], extending themetamaterial physics from wave to diffusion systems (right part of C1 in Fig.2.1).

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Ketersediaan

Informasi Detail

Judul Seri

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No. Panggil

536.7 LIU t

Penerbit

Singapore : Springer Nature., 2023

Deskripsi Fisik

342 hlm

Bahasa

English

ISBN/ISSN

9789811959080

Klasifikasi

536.7

Tipe Isi

text

Tipe Media

computer

Tipe Pembawa

online resource

Edisi

-

Subjek

Thermodynamics

Info Detail Spesifik

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Pernyataan Tanggungjawab

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Versi lain/terkait

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