Sharif Digital Repository

Nonlinear identification of a narrow cantilever blade undergoing free vibration was studied. In the absence of forced excitation and because of general data deficiency of this system, the current identification methods cannot be applied with sufficient accuracy. A new identification approach was introduced in the present study based on nonlinear free vibration decay. Nonlinear free response of the presented system is determined by the coupling of generalized variation iteration and the modified differential transformation methods. The comparisons between the experiments and calculations is highlighted the good accuracy of the identified nonlinear model. © 2020 Faculty of Engineering,... 

Electrical efficiency of photovoltaic (PV) modules depends on their working temperature. Effective cooling is required in order to achieve higher performance. Pulsating heat pipes (PHPs) are compact heat transfer devices with high effective thermal performance due to the two-phase heat transfer mechanism. Since the lower temperature of PV modules leads to higher electricity generation and better efficiency, PHPs can be applied for PV cooling. In this work, the PV cooling by applying a single turn PHP is numerically investigated. In addition, a copper fin with the same dimensions as the PHP for cooling the PV panel is simulated to compare the performance of the PHP with a solid metal like...