Razvoj elementa za prevzemanje energije pri trku vozila

Brili, Danijel (author), Klemenc, Jernej (mentor)

V modernih vozilih so med sprednjim odbijačem in nosilcem motorja vgrajeni porušitveni elementi z namenom, da pri trku absorbirajo kinetično energijo vozila. S strani zavarovalnic so se pojavile zahteve, da se pri trku do 15 km/h porušijo le porušitveni elementi. Trk vozila je dinamičen proces, pri katerem so posledica velike deformacije nosilne strukture v zelo kratkem časovnem intervalu, zato je simulacija takega pojava kompleksna. Uporabljen je Johnson-Cookov materialni model, ki upošteva vpliv hitrosti specifičnih deformacij. Simulacije so izvedene v programu Abaqus Explicit. Simulacija trka je preverjena z realnim eksperimentom in dokazano je, da je simulacija zelo dober približek realnosti. Izbrani so bili trije različni profili porušitvenih elementov, ki so bili vključeni v simulacijo. Oblika profilov je pogojena z izdelavo ekstrudiranja aluminijeve zlitine 6063. Prikazano je, da imata debelina stene in začetna guba velik vpliv na absorbcijo energije. Hkrati je določen tudi pospešek, ki deluje na potnike v vozilu med deformiranjem porušitvenih elementov.

• Language: Slovenian
• Keywords: porušitveni elementi, Johnson – Cook materialni model, plastične deformacije, Abaqus Explicit, trki vozil, absorbcija energije
• Work type: Master's thesis/paper
• Typology: 2.09 - Master's Thesis
• Organization: FS - Faculty of Mechanical Engineering
• Place of publishing: Ljubljana
• Publisher: [D. Brili]
• Year: 2020
• Number of pages: XXIV, 88 str.
• PID: 20.500.12556/RUL-114899
• UDC: 531.66:629.33:004.94(043.2)
• COBISS.SI-ID: 15983619
• Publication date in RUL: 26.03.2020

Secondary language

• Language: English
• Title: Development of an element to absorb energy in a vehicle collision

Abstract

Modern vehicles have built-in crash boxes between the front bumper and the engine mount to absorb the kinetic energy of the vehicle during collision. Insurance companies have demanded that only crashboxes are destroyed during collision up to 15 km/h. Vehicle collision is a dynamic process that results in a large deformation of the supporting structure in a very short time interval. Simulaton of collision is very complex. A Johnson–Cook material model is used to follow agreement of the influence of the rate dependent specific deformation. The simulations were made in Abaqus Explicit. The collision simulation was verified by a real experiment and it was proven to be very good approximation to the reality. Three different profiles of crashboxes were selected and included in the simulation. The shape of the profiles is conditioned by the extrusion of aluminum alloy 6063. It is shown that the wall thickness and the initial fold have a great unfluence on the energy absorption. The deceleration affecting affecting the passengers in the vehicle during the collision was also determined for the considered crash boxes.

• Keywords: crash boxes, Johnson – Cook material model, plastic deformation, Abaqus Explicit, vehicle collisions, energy absorbtion