In this paper, topology optimization (TO) is applied to determine the form, size and location of holes for the special form of Perforated steel plate shear wall (PSPSW). The proposed model is based on the recently presented particular form of PSPSW that is called the ringshaped steel plate shear wall. The strain energy is selected as the objective function in the optimization. Simple Isotropic Material with Penalization (SIMP) method and the solution algorithms, including sensitivity and condition-based methods are utilized in the TO. Four initial plate forms are presented in the TO with regards to the length of the connection between the plate and column. Based on the solution methods and initial forms of the plate, eight scenarios are proposed and seven different Perforated plates obtained using TO. The nonlinear responses of the optimized Perforated plates are compared together, and with the ring-shaped model as a benchmark. The nonlinear analysis is conducted under cyclic and monotonic loadings. Key issues include cyclic and monotonic behavior, pinching behavior, stiffness, load-carrying capacity, energy dissipation, fracture tendency and out-of-plane deformation are investigated and discussed. The results demonstrate the optimized models have better behavior than the ring-shaped model without changing the volume of the plate.

Thin Perforated Steel plate Shear (SPS) Walls are among the most common types of energy dissipating systems. The applied holes reduce the shear strength of the plate and allow to decrease the profile size of the members at the boundary of the panel when these systems are used in the typical design of structures. On the other hand, the different fracture locations of these panels are visible when considering the different perforation patterns. This paper reports on the results obtained from the experimental study under cyclic loading of the effect of different hole patterns on the seismic response of the systems and the location of the fracture. According to this, two Perforated specimens by different patterns were considered. In addition, a plate without holes for a better comparison of the fracture location was chosen. The results showed that changing the pattern of the holes causes a change in the fracture location. Moreover, in Perforated specimens, the amount of shear strength did not reduce suddenly after the fracture phenomenon. In the specimen which was Perforated around the web plate, the pinching force was more than any other in the low cycle of the drifts. For this reason, the energy dissipation and initial stiffness were more than up to 3% drift. The experimental specimens were then simulated with a Finite Element (FE) method using the ABAQUS. Finally, a parametric FE analysis on different series of Perforated panels, by changing the diameter of the holes and the plate thickness, has been carried out.

This paper experimentally and numerically investigated the impact of a blunt projectile to Perforated steel targets. In this study, projectiles were made of AISI 52100 and Perforated plates were made of AISI 1045. In order to investigate the effect of the hole diameter on the projectile, three different diameters of the hole were considered, along with the effect of the projectile overlap with the hole. After examining different hitting states, the projectile was deviated from its movement direction after hitting the hole and changed from vertical hit to skew. The deviation of the projectile increased when the diameter of the hole increased or the amount of projectile overlap with the hole increased. Then, numerical modeling of impacting the projectile was performed by ABAQUS software and the results were compared with experimental results and the accuracy of the model was confirmed. And this model was used to investigate the effect of initial projectile speed on deviation of the projectile, accordingly, an increase in the initial velocity of the impact led to an increase in the deviation of the projectile.

The current study introduces and analyzes a novel square cross-flow Perforated solar air heater (SAH). Since the convection mechanism in SAHs is weak, numerous methods have been suggested to address this problem and improve thermal efficiency. Perforations and cross-flow configuration generate high turbulency and, consequently, high convection rate resulted. Hence these methods have been applied to enhance thermal efficiency. To achieve this goal, an experimental setup was fabricated and tested at outdoor conditions for two air mass flow rates (mair) of 0.015 kg/s and 0.03 kg/s while several sensors monitored the collector’s heat dynamics and ambient conditions. The obtained results illustrate that outlet temperature reaches the peak values of 38 oC and 34 oC, which is only 6 oC and 7 oC lower than the maximum absorber temperature. This crucial issue proves a high heat exchange rate in the fabricated SAH that causes the absorber temperature to approach the outlet temperature due to high turbulency. The strong convection mechanism in the fabricated SAH improves daily thermal efficiency, in which its value reaches nearly 78.6% for the mass flow rate of 0.03 kg/s. In conclusion, the square cross-flow Perforated SAH is an economy, applicable, compact collector, ensuring high thermal efficiency.

Nowadays, different industries are using sheets, plates, and shells as important parts of their components. Because of their small thickness compare to other dimensions, their structural safety requires more attention. Therefore, increasing their strength and intensifying their resistance against any kind of failure type could be introduced as an important problem for enhancing the structural safety. Buckling is one of the most significant failure type that should be considered in the stability of any parts such as sheet metals. Thus, investigation of the buckling capacity of the sheet metals is remarkable. On the other hand, the existence of discontinuity like holes and notches in sheet metals can decrease their buckling capacity, significantly. In current study, based on Finite Element Method (FEM), ABAQUS/Explicit has been employed to determine the elastic buckling capacity in a Perforated rectangular sheet metal with different boundary conditions on its edges. Afterward, the effect of the hole position and the plate aspect ratios (plate length/plate width) on the buckling capacity of sheet metal was studied. Finally, in order to enhance the sheet metal buckling capacity, two different types of stiffeners were used. The outcomes showed that the maximum buckling coefficient is related to the sheet metal which have four clamped edges. Moreover, For all boundary conditions, the buckling coefficient does not change significantly for the sheet metals with aspect ratio of more than 4. Also, stiffener type 2 increased the buckling capacity of sheet metal up to 83%.

The indispensable vital structure in any harbor is a breakwater in order to make available calm water region inshore. Pile breakwater can be employed as small coastal-protection structure where tranquility required is low. This study is concerned with CFD study on performance of Perforated hollow pile to dissipate wave energy and the novelty of this investigation is the role of perforation layout to dissipate energy of water. Pile models under two different incident waves with constant water depth and wave amplitude have been classified into two groups with two different wavelengths, making a total of 10 models which has been simulated numerically by computational flow solver FLOW 3D. The analytical results of simulations show changes in the velocity profiles after piles while dissipation happened in the vicinity of the pile. The results implied that the Perforated models can perform better than the nonPerforated ones and energy dissipation was found much more significant in Perforated piles because dissipation goes on for about 2. 5 m after the pile for the Perforated case, while for the non-Perforated case this distance reduce to 1. 5 m after pile.