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Fin-Metal Foam Hybrid Structure for Enhancing Solid–Liquid Phase Change
Published in Moghtada Mobedi, Kamel Hooman, Wen-Quan Tao, Solid–Liquid Thermal Energy Storage, 2022
Xiaohu Yang, Ming-Jia Li, Kamel Hooman
Metal foam has an open porous structure with a series of advantages such as high thermal conductivity, high porosity, and large specific surface area (see Figure 8.4a). It has a periodic structure similar to that of a tetrakaidecahedron. PCMs fill the pores made by the interconnected ligaments as depicted in Figure 8.4b. The high thermal conductivity skeleton can efficiently transfer heat into the PCM and evenly spread it in a larger volume. While accelerating the heat transfer process, thanks to the high porosity (>90%) of metal foam which can be achieved without compromising the structural integrity the TES capacity will not be significantly reduced [35,36].
Choice of materials and processes
Published in William Bolton, R.A. Higgins, Materials for Engineers and Technicians, 2020
A metal foam is a cellular structure consisting of a solid metal containing gas-filled pores. The pores can be closed or open. Typically, 75–95% of the volume of a metal foam consists of voids, making these materials very light but stiff. Metallic foams tend to retain some physical properties of their base material but notably with a reduced thermal conductivity.
Nonthermal and Alternative Food Processing Technologies
Published in C. Anandharamakrishnan, S. Padma Ishwarya, Essentials and Applications of Food Engineering, 2019
C. Anandharamakrishnan, S. Padma Ishwarya
The heating system of a nanospray dryer includes open-pore metal foam, arranged between the air inlet and outlet; the outlet directly opens to the spray-drying chamber. Metal foam encompasses a large volume fraction of gas-filled pores in a solid metal to form a cellular structure. The advantage of metallic foam is its ability to uniformly heat the entire volume of air flowing through it (Schön and Baumgartner, 2009). Pores in the metal foam structure can be sealed to result in closed-cell foam, or they can be interconnected to form an open-cell foam. The open-celled metal foams enable an effective heat transfer from the metal foam to the drying medium, owing to its large surface area.
Experimental Study of the Metal Foam Suppression Effect on the Gas Deflagration and Detonation
Published in Combustion Science and Technology, 2022
Hao Shao, Huan Hu, Shuguang Jiang, Zhengyan Wu
Metal foam has the advantages of small bulk density, high strength, large pore surface area, good air permeability, etc. It also has characteristics of sound absorption, heat insulation, vibration absorption, shock energy absorption, etc. The metal foam used for the experiment is the copper foam with a pore density of 70PPI. The average pore size is 0.35 mm. The porosity is 95%, and the bulk density is 0.25 g/cm3. The cross section of each piece of the metal foam is 20 mm × 20 mm, which is the same as the section of pipe, and the thickness is 10 mm. In order to prevent the metal foam from moving under shock wave, the metal frame was made to fix the metal foam. Figure 3 shows the metal foam fixed on the metal frame and 3 pieces of the metal foam fixed in the pipe.
Flexural wave dispersion characteristics of imperfect Ti-6Al-4V foam circular cylindrical shells in a thermal environment
Published in Waves in Random and Complex Media, 2021
Chunwei Zhang, Huidong Cao, A. Eyvazian, Afrasyab Khan, Naeim Farouk, Pooya Sareh
One of the essential parameters in the design and analysis of structures is the weight of their constitutive materials. Various lightweight materials have been widely exploited for numerous engineering applications owing to their favorable properties. Porous materials such as metal foams, ceramic foams and graphene foams are among the most ubiquitous classes of lightweight materials with diverse applications in the automotive, aerospace, marine and civil engineering industries. For instance, aluminum foams have been utilized for energy absorption to reduce the structural mass of vehicles in the automotive industry [1,2]. A metal foam is a cellular structure consisting of solid metal with gas-filled pores, which comprise a large portion of its volume. As such a structure is typically strong and lightweight, the mechanical properties of porous materials have been the focus of numerous investigations over the last two decades [3–5]. More specifically, porous functionally graded materials (FGMs) are considered to be generally desirable in terms of structural mass; hence analyzing their mechanical behavior has been an interesting topic for scientists and engineers. For example, the dynamic response of doubly-curved nanosize shells made of porous FGMs based on the nonlocal strain gradient theory (NSGT) was analyzed by Karami, Shahsavari [6]. Furthermore, the influence of imperfections on the vibrational behavior of FGMs tapered nanoscale beams and plates in a thermal environment according to NSGT was surveyed by Karami, Janghorban [7], Karami, Shahsavari [8].
Low-velocity impact of clamped slender rectangular sandwich tubes with metal foam core
Published in International Journal of Crashworthiness, 2021
Jianxun Zhang, Yuqing Zhu, Yang Ye, Hui Yuan, Qinghua Qin
Lightweight tubes [1] are widely adopted in critical engineering, such as aerospace, aircraft, ships, etc. Also, metal foam is a kind of lightweight material with a number of advantages [2], such as high specific stiffness, high specific strength and energy absorption. The lightweight tube and filled foam can form foam-filled tubes. Many researchers focussed on the mechanical properties of foam-filled tubes under different conditions [3–8]. Compared with foam-filled tubes, sandwich tubes with metal foam core have different performances and better energy absorption efficiency [9–11].