Volume 8, Issue 4, October 2014, Pages 1669–1678
Galal A. Hassaan1
1 Department of Mechanical Design & Production, Faculty of Engineering, Cairo University, Giza, Egypt
Original language: English
Copyright © 2014 ISSR Journals. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Door closing mechanisms are used in all building venues using air conditioning systems to reduce thermal losses. One of the closing mechanisms is the torsional type. The visco-elastic characteristics of the closing mechanism may exhibit certain sort of nonlinearities from its linear characteristics. The dynamics of the door with nonlinear characteristic with positive and negative deviation from the linear characteristics of the door closing mechanism are studied. The system dynamics are defined by a nonlinear ordinary second-order differential equation which is solved using Runge-Kutta 4 technique through the MATLAB environment. Two types of nonlinearity are considered depending on the deviation from the linear characteristics of the closing mechanism. One type reveals dynamic behaviour similar to that of overdamped linear dynamic system while the other type reveals dynamic behaviour similar to that of underdamped linear dynamic system. The second type has large effect on the door dynamics where the maximum deviation in the door dynamic response may exceed 700 % from the linear characteristics of the door.
Author Keywords: Automatic door closing mechanism, Nonlinear mechanism characteristics, Door dynamics.
Galal A. Hassaan1
1 Department of Mechanical Design & Production, Faculty of Engineering, Cairo University, Giza, Egypt
Original language: English
Copyright © 2014 ISSR Journals. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Abstract
Door closing mechanisms are used in all building venues using air conditioning systems to reduce thermal losses. One of the closing mechanisms is the torsional type. The visco-elastic characteristics of the closing mechanism may exhibit certain sort of nonlinearities from its linear characteristics. The dynamics of the door with nonlinear characteristic with positive and negative deviation from the linear characteristics of the door closing mechanism are studied. The system dynamics are defined by a nonlinear ordinary second-order differential equation which is solved using Runge-Kutta 4 technique through the MATLAB environment. Two types of nonlinearity are considered depending on the deviation from the linear characteristics of the closing mechanism. One type reveals dynamic behaviour similar to that of overdamped linear dynamic system while the other type reveals dynamic behaviour similar to that of underdamped linear dynamic system. The second type has large effect on the door dynamics where the maximum deviation in the door dynamic response may exceed 700 % from the linear characteristics of the door.
Author Keywords: Automatic door closing mechanism, Nonlinear mechanism characteristics, Door dynamics.
How to Cite this Article
Galal A. Hassaan, “Dynamics of a Nonlinear Automatic Door Closing Torsional Mechanism,” International Journal of Innovation and Applied Studies, vol. 8, no. 4, pp. 1669–1678, October 2014.
