Amirkabir University of Technology

About: Amirkabir University of Technology is a education organization based out in Tehran, Iran. It is known for research contribution in the topics: Nonlinear system & Finite element method. The organization has 15254 authors who have published 31165 publications receiving 487551 citations. The organization is also known as: Tehran Polytechnic & Tehran Polytechnic University.

Direct contact membrane distillation for seawater desalination

Abstract: Membrane distillation (MD) is a non-isothermal membrane separation process. It is based on the phenomenon that pure water in its vapor state can be extracted from aqueous solutions, with vapor passing through a hydrophobic microporous membrane when a temperature difference is established across it. In this work, three commercially available hydrophobic microporous membranes were used for seawater desalination via direct contact MD. The effects of pertinent operating parameters on the permeation flux have been studied. A plate and frame module was used for seawater desalination. Long-term performance evaluation was carried out to evaluate the process as a stand-alone desalination alternative. The results indicated that polytetrafluoroethylene membrane had the best performance when a hot feed temperature of 80°C with 800 ml/min flow rate was used. At optimum condition a 99.99% salt rejection was achieved.

Thermal buckling analysis of functionally graded material beams

Abstract: Buckling of beams made of functionally graded material under various types of thermal loading is considered. The derivation of equations is based on the Euler–Bernoulli beam theory. It is assumed that the mechanical and thermal nonhomogeneous properties of beam vary smoothly by distribution of power law across the thickness of beam. Using the nonlinear strain–displacement relations, equilibrium equations and stability equations of beam are derived. The beam is assumed under three types of thermal loading, namely; uniform temperature rise, nonlinear, and linear temperature distribution through the thickness. Various types of boundary conditions are assumed for the beam with combination of roller, clamped and simply-supported edges. In each case of boundary conditions and loading, a closed form solution for the critical buckling temperature for the beam is presented. The formulations are compared using reduction of results for the functionally graded beams to those of isotropic homogeneous beams given in the literature.