Plates with interior openings are often used in both modern and classical aerospace, mechanical and civil engineering. The understanding of the effects of two cutouts on the stress concentration factor, maximum stress and deflections in perforated clamped rectangular plates, were considered. Parameters such as location, size of cutout and the aspect ratio of plates are very important in designing of structures. These factors were presently studied and solved by finite element method (ANSYS) program. The results based on numerical solution were compared with the results obtained from different analytical solution methods. One of the main objectives of this study is to demonstrate the accuracy of the analytical solution for clamped square plate. In general, the results of the square clamped plates with two cutouts come out in good agreement. The results presented here indicated that the maximum stress, deflection of perforated plates can be significantly changed by using proper cutouts locations and/or size. The results show that the rectangular plate containing two cutouts arranged along the width is stronger and stiffer than when arranged along the length at a given spacing, and the square plate is always stronger and stiffer than an equivalent rectangular plate for the same loading condition.
Free vibration analysis of a cracked cantilever beam with two types of additional substructure attachment is investigated using ANSYS program. The cantilever beam is used as a master structure with single substructure attachment in various locations (as 1-DOF mass attachment and 1-DOF mass-spring attachment) with influence of crack in different location and depths. The results for the changes of the natural frequencies of a cracked beam are compared with the results produced by Vahit et al [1]. So the same geometrical properties have been studied. In additional work a cracked beam carrying two types of substructure attachment are compared with the results of the beam without a crack and with multi crack depth. In all calculations the beam has a uniform cross-section and the crack was modeled by reduction in the modulus of the beam. The reducing effects of the cracked beam on the natural frequencies had been more apparent with the substructure attached to the beam in different situations. The effect of mass-spring substructure is larger than the effect of the attachment when modeled as mass substructure for the same mass, with 17% for the first natural frequency and 2% for the second and third natural frequencies. The results can be used to identify cracks in simple beam structure; cracks have a clearer decreasing impact on the natural frequencies.
Composite laminate plates, fabricated by bonding fiber–reinforced layers, were dynamically analyzed under different combinations of number of layers, type of cutout, hole dimensions, angle of lamination and type of dynamic loading . This work was achieved by the well–known engineering software (ANSYS). The toughness of composite plates was evaluated in terms of the normal stress in the direction of loading at the periphery of the cutout. The toughness was found to increase by increasing the number of layers, by setting the lamination angle at around 40o,by selecting hole dimensions to width of plate ratio of around 0.4 and by employing square cutouts or avoiding triangular cutouts. Also, composite plates were found to be more strain-rate-sensitive in ramp loading, with least number of layers and with triangular type of cutout.
Recently, the investigations studies of simulating flow over spillways have increased using numerical models. Due to its important structure in the dams to pass flood wave to the downstream safely. Researches finding have shown that CFD (Computational fluid dynamics) models as the numerical method are a perfect alternative for laboratory tests. Performance analysis of the CFD platforms Ansys Fluent-2D and Flow-3D are presented, focus on finding the variations between the numerical results of the two programs to simulate the flow over ogee spillway. The present study treats the turbulence using RNG k-ε of RANS approach, and also use the Volume of Fluid (VOF) algorithm to track the water-air interaction. The Fluent-2D and Flow-3D accuracy are assessed by comparing representative flows variables (velocity; free surface profiles; pressure; and the turbulent kinetic energy). The results of both codes have been also compared with experimental data. The results of the analysis show an excellent agreement between the two platforms data, which could assist in the future by using both programs to calibrate each other, rather than traditionally relying on laboratory calibration models.
The nonlinear finite element analysis has become an important tool, for the structural design and assessment of prestressed reinforced concrete members. However, design and assessment of torsion are still done with simplified analytical or empirical design methods. This paper pre-sents results from a numerical analysis using the ANSYS finite element program to simulate a prestressed concrete beams subjected to static and cyclic torque. The eight- node brick ele-ments SOLID65 are used for the idealization of concrete while the reinforcements are idealized by using 3D spar element LINK8. The steel plates are idealized by using three dimensional solid elements SOLID45. The results showed that the general behavior of the finite element models represented by torque- twist angle relationships show good agreement with the experimental results from the Abdullah's beams.
This paper presents an analytical investigation which includes the use of three dimensional nonlinear finite elements to model the performance of the space trusses by using (ANSYS 11.0) computer program. The numerical results show very good agreement (100%) with experimental results, while the graphical option reflects the behavior of the structure under the applied loads because of the ability of this option to simulate the real behavior of the structure under these loads. Also finite element models of the space truss simulate the lateral deflection of the top chord members especially at the corners, and the twisting of the bottom chords.
This study focuses on improving the thermal comfort in Mosques in Iraq. Omar bin Abdul Aziz Mosque in Baghdad is taken as a case study. In general, the weather in Baghdad is hot- dry climate during the summer. the study was conducted at the time of noon prayer on Friday where the maximum number of people can be obtained inside the Mosque about 500 worshipers and severe environmental conditions. Numerical methods (CFD) are used for the simulation utilizing the package of ANSYS (FLUENT V. 18). As the results depending on the number of elements, 4 millions elements are used for dividing the physical domain. Thermal comfort was assessed by finding the values of the predicted mean vote (PMV), predicted percentage of dissatisfied (PPD), and ASHRAE standard-55. The adaptive redistribution of the air conditioning device strategy at five cases is used to obtain the best thermal comfort. Moreover, changing the angle of air intake of space by changing the angle inclination of the access blade at three different angles of 0o, 7.5o and 15o degree, and studying its effect on the thermal comfort in breathing level. The four case is the best in terms of thermal comfort when the angle of intake air at 0o.when the PMV was 0.35 and PPD is 7.5, which is lower than the original state. The improving percentage of PPD is 10 % and PMV 14 %.
In this study, a numerical investigation on the thermo-hydraulic performance of thedouble pipe heat exchanger into heat transfer by different shapes of fins on the outersurface for the inner tube as extended surfaces. The inner and outer diameters of theinner pipe were (16.05 mm), (19.05 mm) respectively, and (34.1 mm), (38.1 mm) for theouter tube. The length of the heat exchanger was (1000 mm). Hot and cold water wereused as the working fluid, where the hot water flows inside of the inner one in counterflow with the cold water which flows in the annulus. The inlet temperature for the hotwater is (75 OC) while it is (30 OC) for the cold. The hot fluid flows at constant ratewhich is (0.1kg/s) while the cold is varied from (0.1 kg/s to 0.2 kg/s).The study wasperform using the known commercial CFD package (ANSYS – FLUNET 15) .Theresults shows that both (rectangular and triangular) fins enhances the heat transfercoefficient compare with the conventional plain tube .The rectangular fins presents anheat transfer enhancement ratio of (61% to 74%). Using of extended surfaces present agood result in saving energy by enhancing the performance of the double pipe heatexchangers used in petroleum industry.
The Cooper-Harper rating of aircraft handling qualities has been adopted as a standard for measuring the performance of aircraft. In the present work, the tail plane design for satisfying longitudinal handling qualities has been investigated with different tail design for two flight conditions based on the Shomber and Gertsen method. Tail plane design is considered as the tail/wing area ratio. Parameters most affecting on the aircraft stability derivative is the tail/wing area ratio. The longitudinal handling qualities criteria were introduced in the mathematical contributions of stability derivative. This design technique has been applied to the Paris Jet; MS 760 Morane-Sualnier aircraft. The results show that when the tail/wing area ratio increases the aircraft stability derivative increases, the damping ratio and the natural frequency increases and the aircraft stability is improved. Three regions of flight conditions had been presented which are satisfactory, acceptable and unacceptable. The optimum tail/wing area ratio satisfying the longitudinal handling qualities and stability is (0.025KeywordsLongitudinal Handling---Stability---Tail Design
Modeling and simulation are indispensable when dealing with complex engineering systems. It makes it possible to do essential assessment before systems are built, Cantilever, which help alleviate the need for expensive experiments and it can provide support in all stages of a project from conceptual design, through commissioning and operation. This study deals with intelligent techniques modeling method for nonlinear response of uniformly loaded paddle. Two Intelligent techniques had been used (Redial Base Function Neural Network and Support Vector Machine). Firstly, the stress distributions and the vertical displacements of the designed cantilevers were simulated using (ANSYS v12.1) a nonlinear finite element program, incremental stages of the nonlinear finite element analysis were generated by using 25 schemes of built paddle Cantilevers with different thickness and uniform distributed loads. The Paddle Cantilever model has 2 NN; NN1 has 5 input nodes representing the uniform distributed load and paddle size, length, width and thickness, 8 nodes at hidden layer and one output node representing the maximum deflection response and NN2 has inputs nodes representing maximum deflection and paddle size, length, width and thickness and one output representing sensitivity (∆R/R). The result shows that of the nonlinear response based upon SVM modeling better than RBFNN on basis of time, accuracy and robustness, particularly when both has same input and output data.
This investigation provides experimental results and nonlinear analysis by using finite element model of thick hollow core slab made from recycled lightweight material. Four hollow core slabs specimens were cast and tested in this investigation with dimensions (1200mm length, 450mm width and 250mm thickness). The crushed clay brick was used as a coarse aggregate instead of gravel. The iron powder waste and silica fume were used in order to increase the compressive strength of concrete. The techniques reduction hollow length and use shear reinforcement were used to improve shear strength and avoid shear failure. The specimens were tested by applying two-line load up to failure. The experimental results were showed these techniques were resisted the shear failure significantly and works to change failure mode from shear to flexural failure. Finite element computer software program (ANSYS) was used to analysis hollow core slabs specimens and compare the experimental results with the theoretical results. Good agreement have been obtained between experimental and numerical results.
Viscoelasticity, as its name implies, is a generalization of elasticity and viscosity. Many industrial applications use viscoelastic matrix with reinforcement fiber to obtained better properties. Tensile testing of matrix and one types of fabric polyamide composites was performed at various loading rates ranging from (8.16* 10-5 to 11.66 * 10-5 m/sec) using a servohydraulic testing apparatus. The kind of reinforcement, random glass fiber (RGF), and the kind of matrix, epoxy (E) are used shown that the linear strain (،ـ 0.5) for the three parameter model gives a good agreement with experimental results. The results showed that both tensile strength and failure strain of these matrices and composites tend to decrease with increase of strain rate. The experimental results were comparison with numerical results by using ANSYS 5.4 program for simple study case has shown some agreement. Fracture regions of the tested specimens were also observed to study micro mechanisms of tensile failure.
In recent decades, functionally graded porous structures have been utilized due to their light weight and excellent energy absorption. They have various applications in the aerospace, biomedical, and engineering fields. Therefore, the balance between material strength and light weight is the goal of the researchers to decrease the cost. Samples of PLA material were designed and manufactured using a 3D printer according to international standard specifications to study the effect of porosity gradient through thickness. An experimental three-point bending test was performed, and then simulations were performed using ANSYS 2022 R1 software on samples with functionally gradient different porosity layers to verify the experimental results. The results from the experiment and the numerical values were in excellent alignment with an error rate of no more than 13%. The maximum bending load and maximum deflection of the beam were specified experimentally and compared with the numerical solution. The maximum bending and the maximum deflection When the porosity layer in the middle of the beam, matched the ideal maximum bending load (190,194) N experimentally and numerically, respectively. The maximum deflection (5.9,6.4) mm experimentally and numerically, respectively was obtained in samples with varying porous layers.
The demand for strengthening structures becomes necessary when an increase in load is inevitable. For instance very little information is available on the time-dependent behaviour of strengthened concrete columns. Also, this is a primary factor hindering the widespread uses of FRP strengthening technologies in the construction implementations. This paper investigates the behaviour of strengthened concrete columns with FRP sheets subjected to long-term loading by non linear finite element analysis using ANSYS computer package. A three-dimensional finite element model has been used in this investigation. This study achieved a good agreement between numerical and experimental results, it was found that the percentage of error of specimens do not pass (5%) for creep strain. In addition, a parametric study was performed to study the effect of different factors on the behaviour of FRP strengthened concrete columns.
Recently, the use of sandwich panels has become increasingly important. This is due to its good mechanical properties and high strength-to-weight ratio. It is used in many fields, especially in aviation, construction and aerospace. It is necessary to know the behavior of the materials used, especially the free vibrations, to know the effect of external factors on the sandwich panels. The honeycomb core sandwich panel was studied. A model for analysis and modeling is proposed. A previous model was chosen for analysis and comparison. Hoff theory was applied to convert honeycomb sandwich panel into equivalent sandwich panel to facilitate the solution and save time. The limits were considered fixed on the one hand and moving on the other hand, and the ANSYS program was used to analyze and extract the results, and the results were compared and were promising and accurate, which proves to us the validity and accuracy of the proposed theoretical results
This research presents an experimental and theoretical investigation of the effect of cutouts on the stress and strain of composite laminate plates subjected to static loads. The experimental program covers measurement of the normal strain at the edges of circular and square holes with different number of layers and types of composite materials by using strain gages technique under constant tensile loads. A numerical investigation has been achieved by using the software package (ANSYS), involving static analysis of symmetric square plates with different types of cutouts. The numerical results include the parametric effects of lamination angle, hole dimensions, types of hole and the number of layers of a symmetric square plate. The experimental results show good agreement compared with numerical results. It is found that increasing the number of layers reduces the value of normal strain at the edges of circular and square holes of a symmetric plate and the maximum value of stress occurs at a lamination angle of (30o) and the maximum value of strain occurs at a lamination angle of (50o) for the symmetric square plates subjected to uni-axial applied load. The hole dimensions to width of plates ratio is found to increase the maximum value of stress and strain of a symmetric square plate subjected to uniaxial applied load. Moreover, the value of maximum stress increases with the order of type of circular, square, triangular and hexagonal cutout, whereas the value of maximum strain increases with the order of type of circular, square, hexagonal and triangular cutout.
This paper presents a nonlinear finite element analysis of reinforced concrete beams subjected to pure torsion. A verification procedure was performed on three specimens by finite element analysis using ANSYS software. The verification with the experimental work revealed a good agreement through the torque-rotation relationship, ultimate torque, rotation, and crack pattern. The studied parameters of strengthening by CFRP sheets included strengthening configurations and number of CFRP layers. The confinement configuration methods included full wrapping sheet around the beam, U-shaped sheet, ring strips spaced at either 65 or 130 mm, longitudinal strips at the top and bottom faces, U-shaped strips in addition to the number of layers variable. It was found that the performance of the beam for resisting a torsional force was improved by (33-49%) depending on the method of coating with CFRP sheets and the number of used layers. A change in the angle of twist, as well as the shape of the spread of cracks, was also noticed from the predicted results.
An experimental investigation as well as nonlinear analysis is carried out in this paper to study the behavior of polymer members (Epoxy & Polyester) under direct tension. The ANSYS model accounts for nonlinear phenomenon, such as, Tension Softening Material (TSM) and Enhanced Multilinear Isotropic Softening (EMIS) models. The polymer specimens are modeled using PLANE82 element – eight node plane element – eight node plane element, which is capable of simulating the failure behavior of polymer material members. The intention of this paper is thereby to discuss the proposed softening models to validate the complete Stress-Strain and Load-Deflection response of prismatic specimens subjected to uniaxial tension. The outcomes from the verifications of both modeling techniques have shown good agreement with the experimental results obtained from literature.
In this paper, an analytical solution of a tapered bimodular beam has been developed. An Euler-Bernoulli beam theory with shear deformations has been utilized to obtain the solution. The bimodular beams are different from those unimodular beams in having two different moduli of elasticity one in compression and another in tension. A verification for the solution has been performed using FEM analysis with ANSYS. The results of the program were very close the results of the analytical solution presented in this paper.
A finite element method for free vibration analysis of generally laminated composite plateswith central crack and clamped edges have been studied using ANSYS 5.4 program. The fiber-reinforced composite materials are ideal for structural applications where highstrength-to-weight and stiffness-to-weight ratios are required, where structures must safelywork during its service life. But damages initiate a breakdown period on the structures.Cracks are among the most encountered damage types in the structures. The non-dimensionalfundamental frequency of vibration decreases with presence of cracks because, therigidity of cracked plate decreases. The natural frequency of plates depends on size andshape of the cracks, the effect of number of layers is found to be insignificant beyond fourlayers and the change of fiber orientation increasing the fundamental frequency of vibration.The results obtained have been compared with the available published literature with goodagreement results
The aim of current work is to investigate the tensioned composite plates with two types of cutouts. Many industrial applications use composite matrix with reinforcement fiber to obtain better properties. The objective of this work is divided into two parts, first the experimental work covers the measuring of the normal strain (εx) at the edges of (circular & square) holes that are perpendicular to the direction of the applied loads with different number of layers and types of cutouts of composite materials by using strain gages technique under constant tensile loads to compare with the numerical results. The second part is numerical work, which involves studying the static analysis of symmetric square plates with different types of cutout (circular – square). In static analysis, the effect of the following design parameters on the maximum stress (σx), strain (εx) and deflection (Ux) is studied. This part of investigation was achieved by using the software finite element package (ANSYS 5.4).