Influence of Notches in Corners of Casement Windows on Stress Experienced in the Aluminum Profiles under Thermal Load

J. Arfaoui [1], L. Fromme [1]
[1] University of Applied Sciences Bielefeld, Department of Engineering Sciences and Mathematics, Bielefeld, Germany
Published in 2016

Modern aluminum casement windows consist of an inner and outer profile made of aluminum, which are separated by an insulating bar made of polyamide (see Figure 1). Due to the low heat conductivity of the plastic material the thermal interaction between the living space and the surrounding is reduced significantly, but thermal expansion of the different materials could cause elastic or even plastic deformations of the aluminum parts. A deflection of the window profile can be reduced by notches on the insulating bar. For this purpose, the influence of notches with different lengths on the appearing stresses has been studied using simulation. The numerical results confirm the expected behavior: notches on the insulating bar reduce the appearing stresses in the aluminum profiles and therefore the deflection. On the basis of this simulation, it is possible to optimize existing systems.