Sharif Digital Repository

Thermopneumatic micropump is one type of positive displacement micropumps, which has many applications due to its relatively large stroke volume, low working voltage, and simple fabrication in microscale. In this paper, a numerical study of heat transfer and fluid flow in a valveless thermopneumatically driven micropump is presented. For rectifying the bidirectional flow, a nozzle and a diffuser are used as the inlet and outlet of the chamber. Since the fluid flow is induced by the motion of a diaphragm, the numerical simulation includes fluid structure interaction, which requires applying a dynamic mesh. The domain of solution is divided into two sections; the actuator unit, which contains... 

Modeling is one of the most important steps in analysis and design of structures. Most of the time behavior of floor diaphragms is assumed completely rigid in their plane in order to simplicity in practical design. Although this assumption leads to acceptable results in analysis and design of conventional buildings, erroneous results may assess in some particular buildings—for instance narrow buildings with stiff end walls. Accordingly, behavior of these buildings in future earthquakes opposes those were predicted in design phase, and they are so vulnerable since in-plane deflection of floor diaphragms are striking which cannot be ignored. This thesis investigates the significance of... 

Reinforced concrete slabs carry both vertical gravity loads and in plane forces due to seismic loads. In this study interaction of bending and in plane forces will be considered. Lee et al. in 2007 studied the floor diaphragm behavior. They considered combination of both in plane and out of plane loadings. In the most previous studies, the diaphragm behavior of a floor slab was represented by its behavior under in-plane forces only. With this assumption, analysis of the floor diaphragm was simplified to the two dimensional plane stress problem. For low-rise buildings, the lateral stiffness of the structure is usually higher than high-rise buildings.Tena et al. in 2014 assessed ment the... 

This study investigates the seismic demand in diaphragms, chords and collectors in typical floor systems used in steel structures. These systems include joist-block slabs, open web steel joists, and composite steel decks. The lateral load resisting systems considered were Special Concentrically Braced Frames (SCBF) and Special Moment Frames (SMF) of varying heights. For each system, the influence of using shear connectors for perimeter beams, joist orientation, geometric configuration, and number of stories on lateral force transfer was examined. Nonlinear static and time history analyses were conducted on selected models. Key findings are as follows:
• In joist slab system without shear...