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The losses present in electrical machines are of major concern in modern industrial applications, very high speed drives, aerospace applications and the automotive industry. This paper presents the magnetic characterization of non-oriented steel sheets used for manufacturing permanent magnet synchronous machines and synchronous reluctance machines when these steel sheets are used at higher frequencies...
This paper presents the design of a high-performance 14-pole, 12-slot interior permanent magnet synchronous machine with flux barriers inside the stator iron core and fractional-slot concentrated windings. This work focuses on electromagnetic, mechanical and thermal aspects of the machine design. The specific goal of this work was to design an electrical machine, which will have a small size, high...
In this paper, we present a method for physics-based dynamic deformation simulation of 3D object. In interactive virtual deformation simulation, there are many common linear and non-linear elasticity models for various deformable situations. We discuss constitutive models of common materials and analyze their differences. On account of their homogeneous and isotropic material properties, these models...
Spinal Cord Injury is one of the most important issues of medical society in the world. Problems that the disabled encounter after the accident are significant, namely pressure sores, bone mineral density loss, and disorders in circulation system. The proposed design is a new standing wheelchair that helps the disabled overcome these problems. Affordability and manufacturing problems still exist....
There are many advantages of 1-3 piezocomposite transducers, such as lighter weight, lower specific acoustic impedance. The matching layer is commonly used to expand the bandwidth of composite transducers. The finite element modal of transducer was set up with ANSYS software and the structure of the transducer was optimized. A final 1-3 piezocomposite transducer was designed, which used the first...
The objective of this work is to use the Finite Element Method (FEM) to simulate the performance of a PVDF transducer array to measure temperature gradients through the determination of phase shifts, i.e. time shifts of the waveform of the echo due to a change in the speed of propagation of ultrasound as a result of a change in temperature, they can be interpreted as phase shifts in the frequency...
Monitoring the integrity of structures in the oil and gas industry is a mandatory task that helps preventing both natural disasters and economical losses. This paper presents the optimization of the geometry of a magnetic circuit for the detection of faults in a pipeline by the magnetic flux leakage method. The main goal of these efforts is to perform a sensitivity analysis on the geometrical parameters...
This paper represents the answer to many challenges in terms of numerical models for the transport of pollutants in drinking water. Due to these reasons this paper represents a particular methodology for estimating the velocity and dispersion coefficients. The aqueous solution transport and adsorption was performed using the COMSOL mathematical program.
In order to participate in the Formula SENA ECO, which is a national design and race performance competition using electric drive system vehicles, these must be lightweight, have a lower drag coefficient and high energy efficiency. An engineering redesign has been developed at the vehicle rear section using the CATIA PLM-tool, providing an optimized solution which focuses on main issues and needs...
This study uses formal mathematical optimization techniques based on parametric computationally-efficient models and differential evolution algorithms. For constant-power applications, in the novel approach described, three concurrent objective functions are minimized: material cost, losses, in order to ensure high efficiency, and the difference between the rated and the characteristic current, aiming...
We have previously proposed an imaging technique called Viscoelastic Response (VisR) ultrasound that uses acoustic radiation force (ARF) impulses to assess the viscoelastic properties of tissue. Using two successive ARF impulses in the same region of excitation and monitoring the induced deformation, VisR fits displacements to the mass-spring-damper mechanical model to measure the relaxation time...
This paper presents a simple yet effective method to determine the flux density-magnetic field intensity (B-H) characteristics of the magnetic material used in a salient pole synchronous machine (SPSM). This is achieved by distributing the magnetic field intensity, H, in the different parts of SPSM using 2D Finite Element (FE) simulations and theoretical calculations. The distribution is based on...
The aim of the paper is to present a structural characterization of the bell tower of the Cathedral of Trani (Bari, Italy) collecting the data of two different non-destructive techniques. The tower, built in 1200, is about 60 meters high and has a square plan with a side of about 7.50 meters; moreover, it is connected to the church through a step supported by a pointed arch. Firstly, an Operational...
The wedge bonding process on a sensor chip design has been simulated using three-dimensional FEM, across a range of die bond stiffness's, where the results and analysis thereof are discussed in this paper. Comparisons have been made with respect to the influence of the stiffness of the die bond, which has implications for both the sensitivity and accuracy of the sensors. Soft die bonds are preferable,...
This paper deals with a simulation modelling of a thermoelectric energy harvester for aircraft applications. The aim of this paper is to provide overview of simulation modelling methods, which are used in development process of the autonomic thermoelectric energy harvester. The assumed harvester is based on MEMS technology and is capable to operate as an independent energy source under high range...
This paper describes the importance of residual magnetism in the stator of a brushless exciter used in a self-starting alternator set. It then shows how a pragmatic hysteresis model within finite element simulations of the exciter can be used to optimize the material properties required to obtain the maximum residual exciter armature voltage, while also minimizing the losses associated with using...
A multi-layer piezoelectric actuator (PEA) stacks piezo thin layers which can convert electric energy to deformation. It is widely used to generate nano-scale displacements. It is well known that the more layers one can stack for a given overall PEA length, the more deformation it can produce when excited by the same voltage. As a result, there is a tendency to reduce the thickness of piezo layers...
Wheel speed sensors are commonly used in automotive applications where knowledge of the precise rotational velocity of the wheels is required to determine the vehicle speed or to obtain subtle information about tire pressure, road conditions or to steer modern driver assistance systems like the Electronic Stability Program. The conventional back-bias speed sensor solution requires the design of a...
In 3D through-silicon-via (TSV) interposer package, there are large numbers of micro bumps and micro solder balls, the sizes of the entities in the package having a difference of 3 orders of magnitude. This multi-scale structure brings difficulties to establish the finite element model for analyzing the thermal fatigue life of board-level solder joint. Homogenization method is adopted to avoid these...
The influence of viscoelastic behavior of polybutylene terephthalate (PBT) on reliability of the thermal contact of a spotlight module is evaluated. The contact between a module and the heat sink is evaluated using non-linear finite element model. The viscoelastic behavior of PBT was obtained under multiple frequencies from single cantilever DMA experiments. The relevant viscoelastic parameters (i...
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