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A magnetic actuated capsule microrobotic system (MACMS) is proposed to control the microrobot to complete specific medical tasks, such as medical diagnosis or drug delivery. The structure design and control of the microrobot are optimized. By establishing the dynamic model of the microrobot with spiral structure, the optimal structure parameters are analyzed, and the fluid simulation of the propulsive force and the resistance of the microrobot are carried out by the finite element analysis software to obtain the optimal performance. During the experiment, the peristaltic pump was used for imitating the environment of the gastrointestinal tract, because the human intestinal tract is constantly peristaltic at random speeds. The experimental results indicated that by adjusting the rotational velocity and frequency of the rotating magnetic field, the magnetic actuated spiral jet microrobot could move flexibly in the pipeline where the fluid’s peristaltic velocity is constantly changing medical functions at the desired area for diagnosis. The proposed microrobot and its optimization method make it possible for microrobot to be applied in medical practice.

The excavation of a foundation pit considerably affects the adjacent structures and underground pipelines owing to the change in the stress state of the surrounding soil, resulting in deformation. The study of an actual engineering case was conducted to examine the influence of excavation on the deformation of adjacent subway tunnels. The finite element analysis software PLAXIS 3D was used to simulate the entire excavation process. The structural design of the foundation pit was optimized based on the simulation results to ensure the stability of the foundation pit and the safety of the existing subway tunnel structure. Finally, the safety evaluation of the excavation of the foundation pit that caused the deformation of the adjacent subway tunnel was performed. The influence of the excavation and unloading of the foundation pit on the subway tunnel is closely related to the distance between the subway and the foundation pit, the amount of earthwork excavated at one time, and the engineering geological conditions. The results of this paper can provide useful reference for the design optimization and safety assessment of similar projects.

In this study, compression tests under quasi-static and dynamic states and plate impact experiments were performed on Zr58Cu12Ni12Al15Nb3 bulk metallic glass (BMG). The experimental results demonstrated that the BMG specimen fractured catastrophically without noticeable plastic deformation. Therefore, the Johnson-Holmquist II (JH-2) constitutive model was used to describe the mechanical response of the presented alloy. The constitutive parameters of the Zr-based BMG were determined from the experimental results based on the JH-2 constitutive equations. Subsequently, the constitutive model with the presented material parameters was programmed in the commercial finite element analysis software LS-DYNA to simulate the dynamic compression and penetration process. The good agreement between the numerical simulations and experimental results indicates that the obtained JH-2 constitutive parameters are accurate and effective.

In some clinical situations, the installation of four or more dental implants may be infeasible. Therefore, the installation of protocol-type prostheses with only three implants may be necessary. The mechanical failures can hinder the success of the rehabilitation treatment. Objective: To evaluate and compare the mechanical stress of the metallic prosthetic bar when installed over protocol-type prostheses of three and four implants, and to evaluate the stress on the dental implants. Methodology: Two three-dimensional human jaw models were created. In one model, four dental implants (P4) were designed and in the other model three dental implants (P3) were designed. In both models, according to the arrangement of the dental implants, prosthetic bars were designed. In a finite element analysis software, compressive forces were applied to the ends of both prosthetic bars, simulating the force application during mastication. Tension and stress dissipation were analyzed on the prosthetic bar and dental implants. Results: Both P4 and P3 protocol-type prostheses supported the force efficiently without breaking the bar or the implants. Force dissipation along the bar was more homogeneous in the P3 prosthetic bar than in P4. In addition, P3 implants received a higher concentration of stress in relation to P4 implants. Conclusions: Prosthetic bars and dental implants withstand the stress of load application in both four and three implant protocol-type prostheses. Three-implants protocol showed more satisfactory force dissipation than the four-implant protocol.

A damping model of fiber reinforced composites was established in this study. Meanwhile, the accuracy of the damping model was verified through experiments. Subsequently, the factors affecting the damping ratio and dynamic response under sinusoidal excitation force of fiber reinforced composites were explored and the measures improving the damping ratio were proposed. The damping model of the fiber reinforced composite was applied to its dynamic equation, and then the dynamic response curves were calculated by the direct time integration method, and the calculated dynamic response curves were compared with the experimental dynamic response curves. The two groups of curves almost coincided, verifying the excellent accuracy of the damping model. Additionally, this study discussed the effects of the fiber volume fraction, the thickness of each layer, the number of layers, the orientation of laying-up, and the sequence of layers on the damping ratio and dynamic response of composite material laminates. The damping model proposed in this paper was suitable for calculating the response curves of composite laminates under sinusoidal concentrated loads. The damping model can be used to calculate the response of the laminate in the elastic range. The accuracy of the model was verified through experiments in the frequency range of 10–200 Hz. The method of calculating the dynamic response of fiber reinforced composites proposed in this study can be easily inserted into the finite element analysis software and directly applied to engineering practice.

Background/Objectives: To professionally meet bridge load demands, hollow PC-girders are recently considered for bridge construction, particularly in Japan. Hollow girders are pretensioned girders, which can be a good alternative for ordinary PC-girders by having lightweight, using less material than other beams, and spanning long distances. Hollow PC-girders can be vulnerable to horizontal end cracking at the time of prestressing strand release. Methods: In this study, a nonlinear finite element analysis was performed to investigate the occurrence of horizontal cracks at the time of prestressing at the ends of hollow PC-girders. First, the selected hollow girder was miniaturized to a span length of 4 m required for sufficiently prestressing; then, a standard static prestressing analysis was performed using a finite element analysis software Midas FEA. This software is an analysis tool with standard FEM analysis functions in the construction field and can perform detailed analysis for reinforcements and concrete crack analysis. The software was used to model the girder and investigate the temporal changes of principal stresses at hollow PC-girders’ ends. Findings: The study showed that placing only end-zone reinforcements cannot reduce principal stresses to the level to be less than the concrete’s tensile strength. However, debonding four PC-strands at the ends of the girder alongside the placement of end-zone reinforcements could sufficiently reduce principal stresses to the level to be less than the tensile strength of concrete, and consequently, horizontal cracks were eliminated at the ends of the hollow PC-girder., 論文

The interfacial transition zone (ITZ) is a weak region of recycled concrete. To further study the influence of the ITZ on the damage performance of recycled concrete, a formula for calculating the ITZ thickness is derived, and the ITZ thickness is calculated for various recycled concrete mixtures with a recycled aggregate content of 30%. The concrete model test method and finite element analysis software were used to numerically simulate common concrete and recycled concrete with ITZ thicknesses of 0.05 mm, 1 mm, 2 mm, 3 mm, and 4 mm. The results show that the thickness of the ITZ has an obvious influence on the cracking strength of recycled concrete and that the cracking strength of recycled concrete decreases with increasing ITZ thickness. The cracks in recycled concrete initiate from the ITZ, and the damage degree increases with increasing ITZ thickness. Compared with that of common concrete, the cracking strength of recycled concrete with an ITZ thickness of no more than 2 mm (i.e., the replacement rate of the recycled aggregates is no more than 30%) is not significantly reduced.

The strengthening of the steel beams is the only way to solve the problem of damage due to several factors, The means of support is always associated with the manner and strengthening in terms of the risk and the operational status, The mineral origin of the consolidation is simple and easy in terms of implementation method whenever he has the acceptance and desire to follow this method for that In this study we will strengthen the steel beams in the operating mode and by strengthening them with sheets of CFRP in many shape to reach the best of these methods. The aim of this research is to study the strengthening of steel beams in sheets of CFRP, by means of three shapes and their comparison using many sections and many lengths for modeling purposes .In order to analyze the result, a finite element analysis software ANSYS version 15.0 and software SAP version 16.0 is used. Moreover, a comparison is conducted between results of the ANSYS and SAP program by conducting laboratory tests for three samples similar in properties and dimensions and different in the shape of the CFRP. A comparison will be made between the load and the deflection of all tested elements, whether the laboratory test or the representation of the section in the ANSYS or SAP program.

Introduction: Mild traumatic brain injury (mTBI) is a common injury, with nearly 3 – 4 million cases annually in the United States alone. Neuroimaging in patients with mTBI provides little benefit, and is usually not indicated as the diagnosis is primarily clinical. It is theorized that microvascular trauma to the brain may be present in mTBI, that may not be captured by routine MRI and CT scans. Electromagnetic (EM) waves may provide a more sensitive medical imaging modality to provide objective data in the diagnosis of mTBI. Methods: COMSOL simulation software was utilized to mimic the anatomy of the human skull including skin, cranium, cerebrospinal fluid (CSF), gray-matter tissue of the brain, and microvasculature within the neural tissue. The effects of penetrating EM waves were simulated using the finite element analysis software and results were generated to identify feasibility and efficacy. Frequency ranges from 7 GHz to 15 GHz were considered, with 0.6 and 1 W power applied. Results: Variations between the differing frequency levels generated different energy levels within the neural tissue—particularly when comparing normal microvasculature versus hemorrhage from microvasculature. This difference within the neural tissue was subsequently identified, via simulation, serving as a potential imaging modality for future work. Conclusion: The use of electromagnetic imaging of the brain after concussive events may play a role in future mTBI diagnosis. Utilizing the proper depth frequency and wavelength, neural tissue and microvascular trauma may be identified utilizing finite element analysis.

Two-high screw piercing of steel 50 billets was performed at feed angles of 15 and 18 degrees. Piercing was stopped at 10–12 mm distance from the rear end of the billet. Axial fracture was registered at 15 degrees feed angle in front of the mandrel nose, while no fracture was observed at 18 degrees feed angle. Piercing for similar parameters was simulated using DEFORM finite element analysis software, and several criteria were used for fracture prediction. Ayada criterion was ineffective, as evidenced by the comparison with experimental data. The normalized Cockcroft–Latham criterion was effective for fracture prediction only in the axial zone. Results of this study showed that the most effective technique for fracture prediction is the construction of a dependence of “accumulated strain–stiffness coefficient of tension” along the trajectory of the point movement.

Cold formed steel is one of the structural materials which are vastly growing product and being used as various structural elements. It has major advantages in time effectiveness and the ability to shape it into the necessary shape even in room temperature. In this study the behaviour of the Steel column having flutes of different shapes when filled with concrete will be analytically investigated by analysing 8 column models using Finite Element Analysis software. Here Cold formed steel is to be used as the hollow section that confines the concrete. The Finite Element Analysis software that will use for the analysis is ABAQUS 14. All the specimens will be loaded with an eccentrically load and the results will be studied further. By providing the flutes along the longitudinal length of the column increases the moment of inertia and the stiffness of the column. The parameters of the column that will be varied for the analysis are the D/t ratios, Shapes of flutes and the thickness of the steel column. High Strength concrete of grade M50 will be used here in this analytical study. The thickness of the steel column used is 1 mm and 1.2 mm. The shapes of the flutes varied is rectangular flute and triangular flute. The maximum stress induced was in the column with 1 mm thickness with triangular flutes. And the maximum load was carried by the Triangular fluted column with 1.2 mm thickness.

In this study free vibration behavior of a stepped beam on an elastic foundation is considered. The vibration of uniform beams on an elastic foundation has been previously studied extensively and various solutions are available in the literature. However, the problem considered in current study appears not to have been widely covered in the literature and analytical solutions are strictly limited. To this aim, semi-analytical solutions are obtained first by using Adomian decomposition method, then finite element solutions are computed via structural finite element analysis software (SAP 2000). The free vibration analysis of stepped beam considering the combinations of different support conditions at each end are performed employing semi-analytical and finite element methods. The findings of the analysis are compared and discussed in detail.

Nickel-based superalloy GH4169 has high strength and stability at high temperature and is widely used in aerospace and military fields.However, due to the problems of hard spots and poor thermal conductivity in actual processing,it is difficult for workers to select reasonable processing parameters during processing,which increases the difficulty of processing.In order to optimize the milling parameters,reduce the milling cost and operational difficulties in actual machining,we used ABAQUS finite element analysis software to simulate the 3D milling of GH4169 nickel base superalloy.The variation of milling force during milling was studied.The influences of milling speed,feed per tooth and radial depth on milling force were analyzed and the results of the simulation were compared with those obtained by orthogonal experiment.The variation of milling force was verified.Finally,we obtained the reasonable milling parameters.

This paper investigates whether the Weibull parameters of the new local approach model for cleavage fractures are affected by the geometric size of the specimen. Based on the fracture test data of A508-C steel, low temperature round notched bar tensile specimens of A508-C steel with two different notch sizes are numerically simulated by using finite element analysis software ABAQUS, and the stress distributions are obtained. The Weibull parameters of two notched bars are calibrated by linear regression method. The results show that the Weibull parameters of the specimens with different notch sizes are different. This suggests that the calibration parameters are dependent on the notch size.

We present a novel consistent singularity-free strain-based finite element formulation for the analysis of three-dimensional frame-like structures. Our model is based on a geometrically exact finite-strain beam theory, quaternion parametrization of spatial rotations, assumption that the strain measures are constant along the length of the element and a proper choice of basis for the translational strain vector representation. As it is common for strain-based elements, the present formulation does not suffer from shear locking. A comparison of our results with the results from the literature and a commercial finite element analysis software demonstrates the advantages of the proposed formulation, especially when the structure is subjected to larger shear deformations. This stems from the fact that our model ensures a mathematically consistent updating procedure for all the quantities describing the beam. This aspect is often overlooked, since most of the numerical cases from other studies on this topic engage rather small-shear strains for which the consistent update is not crucial as the number of elements is increased.

Machine foundations are special type of foundations, designed to carry various loads which have wide range of speeds, loads, and operating conditions. Therefore, in addition to static loads due to the weight of the foundation, they transmit dynamic loads to the soil below. Due to this, the size of the machine foundation required is big, thus making construction cost also huge. To tackle this problem, dynamic properties of the soil upon which the foundation rests can be modified by reinforcing it with geosynthetic material. In this paper, numerical analysis on static as well as dynamic properties of soil has been carried out, by using a finite element analysis software, PLAXIS. The performance of an unreinforced sand was compared with a polypropylene geotextile-reinforced sand. Modeling of the entire setup in PLAXIS 2D 8.6 was done to simulate laboratory model footing test using cyclic plate load test. The effect of depth and width of placement of polypropylene geotextile on improving the dynamic behavior of sand has been studied. The obtained results showed that with the incorporation of geotextile in sand, dynamic properties of sand were significantly improved. It was found that for a time period of 0.05 s, there has been a difference of 10 mm in total extreme displacement when the model with unreinforced and reinforced sand are compared.

The simultaneous turning technique is used to increase the rotary component’s fatigue life by increasing the surface compressive residual stresses. Cutting velocity, cutting tool rake angle, nose radius, feed and tool separation distances are the major cutting parameters in simultaneous turning. Computer simulation was performed by finite element analysis software ABAQUS 6.14. It was used to predict the surface residual stresses and optimization of the cutting parameters was carried out using Taguchi method. MINITAB software was employed for this purpose. The study revealed that the optimal combination of cutting parameters are 150 m/min cutting speed, 0.1 mm/rev feed, 4° negative rake angle, 0.1 mm tool nose radius and 0.4 mm tool separation distance. These optimal values yielded a highest circumferential and axial surface residual stresses of −817.59 and −928.04 MPa for the surface turned by first tool whereas for surface machined by other tool it was −875.89 and −1010.44 MPa.

The usage of fiber reinforced plastic material occupies most of the prominent places in this modern industrial era, which starts from construction industries to automobile sectors. Its versatility and adoptability towards the various applications emphasize their importance as one of the fore most leading and irreplaceable material in most of the predominant areas. In this present work, a series of proportions of vinylester (VER) and (0, 20, 40 wt%) polyurethane (PU) have been blended with each other and concurrently reinforced with E-Glass fiber reinforcement, with the purpose of fabricating the IPN laminate. In order to evaluate the physical strength, their flexural strength of IPN laminate was studied as per ASTM D790 standard. Result reveals that the addition of PU can significantly decreases the flexural stress to strain ratio to the maximum extent, but adversely increases the strain value. To validate this, obtained results from the experimental data’s are cross verified with finite element analysis software ANSYS. The load – deflection curves at mid of the laminate were compared with ANSYS data’s. The precision of the FEM data’s are assessed by comparing with the experimental results, which are shown good agreement. The differences were observed as 8.33%, 0.697%, 1.5944% for 0%, 20%, 40% PU respectively.

In the present work, design modification and stress analysis of blade and stator assembly for turbines using pin and spacer method are carried out. The locker pins are a kind of small device that locks the bucket and inserted them into the grooves. To avoid centrifugal force, a spacer is placed between tangential blades that make more comfort. Design calculations are calculated and the obtained stresses and simulations are performed by using commercial finite element analysis software ANSYS 14.5. Observed stresses on space and locker pins are much below the yield stress of the material

Defects in the form of dimples, straight edges, and wrinkles can easily appear when a multipoint die is used to directly form sheet metal. The main methods currently used to address this issue are to add polyurethane elastic pads between the punch units and the blank or to use a blank holder device. However, the use of polyurethane elastic pads or a blank holder device may reduce the accuracy of the formed die surface or the material utilization ratio, respectively. To improve the outcome, a composite elastic pad for multipoint forming is proposed. Taking a spherical surface of radius R400 as the target surface, numerical simulations and forming experiments using three different forming conditions, namely, without any cushion, with polyurethane elastic pads, and with composite steel pads, were conducted using the finite element analysis software Abaqus and a YAM-200 multipoint forming press, which was independently developed by the Jilin University. The results show that compared with the forming conditions without any cushion and with polyurethane elastic pads, when the proposed composite steel pads are used in multipoint forming, the forming accuracy is effectively improved, and defects in the form of dimples, straight edges, and wrinkles are effectively suppressed. Further research revealed that varying the thickness of polyurethane sheet A or polyurethane sheet B in the composite elastic pad design will result in different effects on forming accuracy and quality improvement. When the thicknesses of polyurethane board A and polyurethane board B are 5 mm and 10 mm, respectively, the forming effect is the best. Compared with forming without a cushion, the maximum error and average error of the formed parts are reduced by 68.3% and 66.1%, respectively.

Sasis merupakan bagian penting dari sebuah kendaraan, yang membentuk kerangka dari sebuah kendaraan. Sasis harus cukup kaku untuk menahan kejutan, twist, getaran dan tekanan lainnya. Pertimbangan penting dalam desain sasis adalah memiliki kekakuan lentur yang memadai disertai kekuatan untuk karakteristik handling yang lebih baik. Oleh karena itu tegangan maksimum, dan defleksi merupakan kriteria penting untuk desain sasis. Tujuan kajian ini untuk menentukan desain paling optimal dari ketiga desain sasis tipe C, I dan Rectangular Box (Hollow). Mendapatkan ketebalan sasis paling minimum pada sasis bus tipe Rectangular Box (Hollow) dari metode optimasi ASO dan MOGA. Serta membandingkan hasil optimasi yang didapatkan dari kedua metode optimasi tersebut. Pada kajian ini digunakan 2 jenis software yaitu software CAD (SOLIDWORKS 2015) untuk pembuatan model sasis bus dan software Finite Element Analysis (ANSYS Workbench v.16) untuk melakukan simulasi pembebanan static structural dan optimasi. Hasil pada kajian ini menunjukan bahwa tegangan maksimum terjadi pada cross section C besar tegangan 73,235 Mpa, dan defleksi sebesar 1,5455 mm. Hasil analisis pembebanan statik menunjukan bahwa desain tipe Rectangular Box (Hollow) jauh lebih optimal daripada tipe C ataupun I. Berdasarkan optimasi pada sasis bus tipe Rectangular Box (Hollow) dengan dua metode tersebut, hasil terbaik menggunakan metode ASO dengan nilai massa optimum sebesar 682,57 kg (persentase penurunan massa sebesar 1,224 %) dengan equivalent (von-misses) stress sebesar 53,557 MPa dan total deformasi sebesar 1,1847 mm. Sedangkan hasil optimasi metode MOGA, massa hasil optimasi sebesar 686,83 kg dengan equivalent (von-misses) stress 53,517 MPa dan total deformasi sebesar 1,1809 mm. Terjadi penurunan massa sebesar 0,608%.

Stress is one of the key factors affecting cold rolling effect. In order to determine the influence of process parameters on cold rolling stress of wear-resistant steel, finite element analysis software ABAQUS was used to analyze the rolling process. In the analysis process, the solver adopts explicit dynamic scheme, and the research method is a single variable method. The stress variation characteristics are calculated under different tension and friction coefficient before and after rolling. According to the analysis results, the stress is related to the tension. The stress increases first and then decreases with the rolling direction. The cold rolling stress can be significantly increased when the friction coefficient increases to a certain value.

The magnetic enrichment behavior of monodispersed MFe2O4 (M = Mg, Ca, Ni, Co, and Cu) ferrite nanoparticles with different size (10–130 nm) on the surface of a 15 mm o.d. NdFeB-N40 magnetic rod has been investigated. The materials were synthesized by a modified sol-gel method. They were characterized by XRD, TEM, and VSM. The magnetic field of the rod was modelled numerically using a finite element analysis software to obtain the input data for the magnitude of magnetic force. Three adsorption models can be used to describe the enrichment mechanism of ferrite nanoparticle depending on the magnetic permeability: (i) Freundlich adsorption model at low magnetic permeability ( 100 μemu/Oe) leading to the enrichment percentage above 90%.

In industrial sheet forming of high strength steel sheets, shear fracture has been reported to occur in narrow die shoulders where the sheet is subject to excessive bending and stretching. For high strength steel plates, which generally show low ductility, the die curvature becomes relatively large for thin sheets, increasing the risk of fracture. Under these circumstances, failure is caused by the shear stresses induced by the high through-thickness stress gradient. Since shear fracture cannot be predicted by the strain-based forming limit diagram, efforts have been made to overcome this limitation and eventually led to the triaxiality failure diagram. In this study, we investigate shear fracture occurring in the forming of thick high strength steel sheets by means of finite element analysis. To do so, we implement the TFD in the commercial finite element analysis software AFDEX through a subroutine. We compare and analyze the predicted damage values obtained for diverse damage models with those obtained via the subroutine so to gain better insight in the theory and background of shear fracture. Finally, the influence of the mesh quality on the predicted stress triaxiality-dependent damage parameter is investigated.

A new fence type blast wall consisting of steel poles was recently proposed based on the idea that the blast wave-obstacle interaction could generate wave reflection, diffraction and out-of-phase interference to reduce the wave energy. The effectiveness of this kind of new blast wall in mitigating blast loading was investigated through 2D numerical simulations and field blasting tests. In this study, 3D numerical simulations are carried out as an extension of the previous studies for a more comprehensive understanding of the effectiveness of fence blast wall. The simulations are performed by using an explicit dynamic finite element analysis software AUTODYN 3D with validated material models. Responses of a reinforced concrete (RC) wall under blast load are also calculated for comparison. Influences of different parameters of the fence wall, including the cross-sectional shape of the steel poles, spacing between poles, number of fence layers and spacing between layers, on its effectiveness in mitigating the blast loadings are investigated. The peak overpressure, impulse and overpressure-time histories behind the fence and RC blast wall are compared with those in free field for evaluation. It is found that the fence blast wall, if properly arranged, could perform equally or even better than the RC wall in mitigating overpressure and impulse of blast wave. Moreover, fence blast wall is less likely to generate the secondary debris hazards associated with the RC and other solid walls when close-in explosion occurs. Therefore, it is an excellent alternative blast barrier in protecting critical structures in urban areas.

Lunar exploration has become increasingly popular, and lunar habitation research must be a core focus during the exploration of the Moon. The lunar habitation research must mainly include architectural and structural designs built using suitable material-forming technology and construction equipment. To address these issues, Chinese Super Mason (CSM) was proposed. This technology is an autonomous robotic construction system that is capable of automated assembling on-site prefabricated multistructural bricks and arched segments. The compound fabrication system was composed of a six-axis robotic manipulator and a dry mixed autoclaving fabricator carried on an autonomous-limbed vehicle platform. The Xuanwu Station for the lunar habitation conceptual design was developed and intended for erection by the CSM. A case study was conducted in a 2.8 m-long, 0.8 m-wide, and 1.1 m-high open arched-formwork structure fabricated within 8.5 h on the Earth. In addition, the Xuanwu Station was evaluated using finite element analysis software considering the temperature, air pressure, and other special environments on the Moon. The reliabilities and limitations of the CSM method were analyzed. Finally, the applications of the CSM in the extreme environment of the Earth and several improvements of the experimental equipment were discussed along with the proposed future applications for autonomous construction.

Hot banding is a typical thermoelastic instability phenomenon that occurs on the sealing surface of the sealing ring in a transmission. The presence of hot banding on sealing contact surfaces causes local wear. The wear of a sealing ring results in the loss of supply pressure and ultimately causes transmission failure. Local wear and hot banding migration also affect each other. This paper has discussed the influence of the wear of the sealing interface on hot banding migration using the general finite element method. A wear simulation procedure, based on Archard's wear law, was used to calculate the wear of the sealing ring, and the thermoelastic effects were also included in the simulation model. An iterative cyclic updating method was performed using the general finite element analysis software. The results of the simulation showed how wear influenced the migration of the hot banding. The worn sealing surfaces lead to more complex migration states of the hot banding, including division and combination of the hot banding. The proposed simulation method and the procedure that was used are suitable for trend analysis of seal design.

This paper considers the use of Nonlinear Finite Element Analysis (NLFEA) to predict the load capacity of a range of experimentally tested in-plane restrained reinforced concrete slabs which experienced internal arching effects under loading. The slabs were constructed at one third scale and strengthened with basalt fibre reinforced polymer (BFRP) or carbon fibre reinforced polymer (CFRP) bonded in place using the near surface mounted (NSM) technique. As the research was representative of existing floor slabs within reinforced concrete building frames, all test specimens were constructed with normal strength concrete (~40N/mm2) and 0.15% steel reinforcement. One tenth of one percent fibre reinforced polymer (FRP) was used to strengthen samples which were compared with unstrengthened control specimens. The London University Structural Analysis System (LUSAS) finite element analysis software package was used to model all test samples using experimentally derived material test values. Experiments and NLFEA models were compared with the Queen’s University Belfast (QUB) arching theory which showed that LUSAS was slightly more accurate than the QUB arching theory in predicting slab capacity. However, the QUB arching theory was found to be slightly more consistent in estimating slab capacities compared with LUSAS. Yet, both of these methods were significantly better at predicting slab capacities than existing Eurocode and American Concrete Institute codes.

In this paper, vibration modal analysis of a horizontal axis micro wind turbine blade of different rotational speeds was carried out by using the finite element analysis software COSMOSWorks. The dynamic stiffening phenomenon and its effect on the vibration mode of the wind turbine blade were taken into account. Numerical results were analyzed and compared. The analysis can help not only to ensure the reliability of system operation but also to improve the structural performance.

Water movement under hydraulic structures through a permeable layer of soil is considered as one of the main causes of failure of hydraulic structures. Therefore, this study aims to minimize the influence of water movement under hydraulic structures by using a filter. The case was simulated using the finite element analysis software ANSYS where many valuables were studied such as head of water, depth of upstream cut off wall, filter depth, and filter location. Such variables usually influence the uplift pressure, exit gradient and seepage discharge, which control the performance of the hydraulic structure. The results have shown that the position of filter at downstream leads to increases the seepage discharge and exit gradient, while at upstream, it reduces the uplift pressure significantly.

In this paper, considering the sufficiency of the verification of functions and interfaces between a large space station system, a digital design method is used to research and design a verification platform, innovatively combining aluminum profiled materials and aluminum honeycomb panel materials, through special profiled corners. Pieces are connected and built to complete the entire structural design. Using this platform structure to perform AIT pre-test verification on a core module, which can find out the problems of a core module system level, complete device level, and inter-segment functions and interfaces as early as possible, and can verify the correctness of the space station system-level electrical functions in advance And rationality, effectively compress the system function test time in the AIT stage, and make up for the shortcomings of current traditional verification platform for the lack of verification of certain functions of whole device. In this paper, the structural module of the verification platform is designed and analyzed in detail, and the safety and reliability of the overall structure of verification platform are calculated and verified by the NASTRAN finite element analysis software. After practical application, the innovation and feasibility of the platform are further verified. It is worth promoting.

The simulation model of MEMS energy changer is established by using the finite element analysis software ANSYS. The electrothermal performance of MEMS energy changer under the action of different currents was simulated and analyzed. The bridge area is made of NiCr, and the shape of the bridge area is two different chamfering rectangles. The temperature distribution diagram of MEMS energy changers, the temperature change curve and the phase transition distribution diagram of the bridge region were obtained when the four current values acted on each other. The simulation results are analyzed and discussed.

In microelectronics assemblies, Thermal Interface Materials (TIMs) are vital to the reliability of the devices in operation. Some electronic devices operate in elevated temperature environments such as military and industrial applications. Hence, the need to evaluate the reliability of such devices at elevated temperatures. Tin-Silver-Copper lead-free solder TIMs have been used during the assembly process of some electronic devices operating under harsh temperature environments. In this study, the reliability of SAC305 lead-free solder TIM was considered at elevated temperatures ranging from 100 oC to 200 oC at 25 oC interval, and aged for about an hour. ANSYS finite element analysis software was employed for the design and evaluation of SAC305 lead-free solder model. The findings of the investigation demonstrated that the higher the harsh temperature environment, the lower the reliability of the SAC305 solder TIM. In addition, the highest fatigue life (36735 or 4.2 years) was recorded at 100 oC, while 200 oC recorded the lowest fatigue life (1014 or 0.12 years). The fatigue life is an indication of the lifespan of the TIM when in operation. This research will be beneficial to engineers assembling microelectronic products. Keywords— elevated temperature; fatigue life; microelectronics; reliability; SAC305 solder

Composites have been used in motorsports, aviation and many industrial machines for decades. In this paper, the recent research works on composites are reviewed. This work explores the possibility of using carbon fiber in different sequences of an inter-ply hybrid composite. This review also concentrates on various tests conducted on a select few composites to test their strength in different areas. The visco-elastic properties of these hybrid composites can be found out by performing dynamic mechanical analysis. Further analysis will be conducted in finite element analysis software. From the results, the most optimal hybrid configuration can be found out.

The finite element analysis software AdvantEdge is used to simulate the milling process of titanium alloy TB8 in two dimensions. Comparing with the experimental results, it can be concluded that simulation results are reasonable. Based on the model, the influences of the milling speed vc, the axial milling depth ap, the per-feed feed rate fz on the milling force are analyzed. The temperature field distribution at different milling speeds and the influence of milling speed on the rake face and relief face of temperature are studied. The results show that when milling titanium TB8, it is recommended to use higher milling speed, smaller axial milling depth and feed per tooth when conditions permit. The temperature distribution of the tool has a significant gradient change, the maximum temperature is located in the rake face of the main cutting edge near the tip of 0.01–0.02 mm position. Most of the cutting heat of Titanium alloy milling process is taken away, and only a small part of the heat is transferred to the tool and workpiece.

Analysis of an earthen dam, especially its slopes, is very important these days as its failure may cause huge loss of lives and properties. These days numerical models are used to check the stability of an earthen dam. Numerical models simulate all the parameters, which affect the safety of an earthen dam. The most important parameters are properties of the soils used for the construction of an earthen dam. For the numerical modeling in this study, a finite element analysis software is used, i.e. GEOSTUDIO 2007 (SEEP/W and SLOPE/W). The parameters considered in this analysis are the site and its foundation conditions, soil material characteristics and hazard potential associated with the particular site. To find the factor of safety, a numerical model of SLOPE/W and SEEP/W program of GEOSTUDIO software is tested for steady-state condition and sudden drawdown. The Morgenstern-Price method, based on limit equilibrium, which is incorporated in SLOPE/W to analyse the model for four cases, namely earth dam without berm and without a toe drain, earth dam with berm without a toe drain, earth dam without berm with a toe drain and earth dam with berm with a toe drain. The results showed that out of four cases, the best case to improve the factor of safety of the slope is the fourth case, i.e. earth dam with berm with a toe drain.

Three-wheeler vehicles are used as one of the major public transportation systems in Ethiopia society. They have played a very important role in a short-distance transport system in Ethiopia especially in city and town. The purpose of this research is to improve the design of the body and structure of three-wheeler vehicles to bring significant change in their overall activity. To fulfil the objectives of this study, the following main activities were performed. CAD model was prepared by using CATIA V5R19 software; structure analysis was done by using finite element analysis (FEA) with ANSYS 16.0 software. Also, for impact analysis such as frontal and rollover static impact analysis, finite element analysis software was used. Designing the overall body and structure improves vehicle stability and handling. This rollover impact simulation is used to bring a great change to protect occupants from rollover accidents.