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Multi-physical contact simulation in Vehicle applications

Schmid Michal, Tomek Petr, Hanus Petr

Production Engineering Archives

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2022

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Vol. 28, Iss. 4

369--374

EN

Multi-physical contact behaviour is important in multiple disciplines related to the automotive industry. Nowadays battery-electric vehicles’ (BEV) thermal management systems deal with contact between bodies where mechanical, electric, and thermal interaction occurs. The battery thermal management itself is crucial for cell life, safety, and everyday vehicle performance. Thus, comprehensive and accurate simulation of the multi-physical contact is a vital part of vehicle development. The multi-physical contact is represented by two or more bodies under applied mechanical load and a current or heat conducted throughout the realized contact area. The amount of conducted current/heat or generated Joule heat is the function of the contact area as well as contact pressure, thus the structural simulation should be essential for such thermal management system simulations Most of the current full vehicle battery pack CFD cooling simulations simplified the multi-physical contact as ideal. Detailed contact modelling is time-consuming, hence not applicable for the full vehicle modelling. In this work, a feasible approach based on contact resistance curves was implemented. Furthermore, the work demonstrates the necessity of correct structural contact prediction for a joule heating and thermal solution.

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Thermal barrier concepts against continuous laser irradiation

Lenarczyk M., Domański R.

Journal of KONES

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2018

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Vol. 25, No. 2

231--238

EN

Rapid development in the high-power laser technology poses new requirements on the thermal protective materials. Military laser applications have been characterized and the examples have been presented. Existing materials, which may be used as a protection against high-energy laser beam, have been discussed. Several concepts of the new thermal barrier materials have been proposed. The proposals include multilayer structures, porous materials, systems with phase change materials (PCMs), and systems with various thermal contact resistance for different contact pairs. Comparative study based on numerical simulation results has been performed to assess efficiency of each proposal. Three major candidate technologies were considered: the CO2 laser, the HF/DF chemical laser, and the Nd-glass solid-state laser. The CO2 combustion driven gas laser was built in mid-seventies. Its power was 500 kW with the poor beam quality. In the context of thermal protection against laser, high conductive material component in a complex structure might be especially useful, since irradiated surface is usually limited to a small size.

3

On the effect of a variable thermal contact resistance on the solidification process

Lipnicki Z., Weigand B., Bydałek A.

Archives of Metallurgy and Materials

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2005

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Vol. 50, iss. 4

1055-1064

EN

In this paper, the influence of a variable thermal contact resistance between a cold plate and a flowing liquid on the solidification process is theoretically analysed. A contact layer which exists between the crust and the cold plate, causes additional resistance for the flowing heat. The structure of this layer is complex. A non-pure substance occupies this volume. Gaps of air can also be present. A non-linear differential equation for the behaviour of the thickness of the solidification front is derived and solved analytically and numerically. In the contact layer there exists temperature difference between the temperature of the frozen layer plane of the opposite cold plate and the temperature of the wall of the cold plate. The thermal contact resistance depends strongly on solidification time. The general shape of this function has been prescribed by using results from other experimental studies.

PL

W pracy określono teoretycznie wpływ zmiennego cieplnego oporu kontaktu między zimną płytą i przepływajacą ciecza na proces krzepnięcia. Warstwa kontaktu powstająca między warstwą zakrzepłą a zimna płyta tworzy dodatkowy opór cieplny. Struktura warstwy kontaktu jest złożona, w objetości, której moga występować zanieczyszczenia i pecherzyki powietrza. Sformułowano i rozwiązano analitycznie i numerycznie nieliniowe równanie różniczkowe opisuje rozwój grubości warstwy frontu krzepnięcia. W warstwie kontaktu występuje różnica temperatur między temperatura powierzchni warstwy zakrzepłej i temperatura powierzchni zimnej płyty. Opór cieplny kontaktu, którego funkcja opisana jest na podstawie danych eksperymentalnych zależy silnie od czasu krzepnięcia.