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In this paper the mathematical and numerical models of the heating process of the medium-carbon (AISI 1045) steel element are presented. The heat equation including the convection term is solved using the Petrov-Galerkin formulation. The temperature fields are determined using the copyright software based on the finite element method (three-dimensional). Influence of assumed material properties on the shape of the heat affected and fusion zones is analyzed. The results obtained from the numerical model are compared to experimental ones. [ABSTRACT FROM AUTHOR]

In this paper, we shall construct a new numerical scheme for fourth-order fractional diffusion wave model. The solvability, stability and convergence of proposed method are established in l2 norm and it is shown that the numerical scheme improves the earlier work done. Simulation is carried out to verity the accuracy and efficiency of the numerical scheme. [ABSTRACT FROM AUTHOR]

The paper presents an algorithm for constructing of synthesizing control function. This algorithm is sufficiently convenient for numerical implementation and a wide class of nonlinear nonstationary systems of ordinary differential equations, provide the passage from initial state into to origin coordinates. We obtain a constructive condition for the choice of initial state for which the passage is possible with regard of the constraints imposed on the control. We consider an problem of control of single manipulator, for which we carry numerical simulation. [ABSTRACT FROM AUTHOR]

This paper presents a comparison of two Cholesky-like algorithms for solving symmetric quasi-definite system Mz = f . This pair of methods computes the block factorization M = RTDR, where R is upper triangular and D is a diagonal matrix. [ABSTRACT FROM AUTHOR]

Any large functioning system consists of equipment that needs to be repaired during its lifetime. The methods of mathematical programming are used to formalize the optimization problem of preventive equipment repair planning in this paper. The method is used to find the annual optimal plan of preventive equipment repair. The goal of such plan is the uniform distribution of repair works by the months. It is supposed, that the deviation from the standard plan of repair works can not be more than one month. An algorithm to find the optimal plan of repair works is provided. A numerical example is given. [ABSTRACT FROM AUTHOR]

The paper contains a model of penetration and electrically accelerated extraction of chlorides from a reinforced concrete structure. A numerical framework is formulated based on the Fick's law, Nernst-Planck equation and Gauss law of electrostatics. Finite element approximation and the Galerkin-Petrov approach is used to solve the task. A sample calculation of extraction of chlorides from a bridge deck taking into account several solution stages like developing of chloride profile by diffusion, calculation of the electric field and accelerated extraction chlorides is performed. The example clearly shows uneven distribution of the computed fields (electric potential, chloride concentration) and uneven efficiency of the method in a real reinforced concrete structure. [ABSTRACT FROM AUTHOR]

The paper focuses on numerical solution of a nonlinear aeroelastic problem. The classical approach of linearized aerodynamic forces is compared to the numerical approximation of the coupled fluid-structure problem. In the second case the finite element method is used for solution of the incompressible Navier-Stokes equations and coupled with the non-linear motion equations of a flexibly supported airfoil. The obtained results are compared to the linearized approach approximations. The influence of the nonlinear terms is discussed. [ABSTRACT FROM AUTHOR]

This paper aims to obtain positive fuzzy minimal solution for positive singular fully fuzzy Sylvester matrix equation (FFSE). A FFSE is said to be singular when the coefficient fuzzy matrix of the equation is not invertible whereby its determinant equal to zero. In obtaining the solution, first of all, the FFSE is converted to fully fuzzy linear system (FFLS) by using Kronecker product and Vec-operator. Then, by applying an associated linear matrix system approach, the crisp form of matrix is obtained. Finally, the solution of the equation is obtained by using method of pseudoinverse. A numerical example is also given in this paper [ABSTRACT FROM AUTHOR]

In this paper, we focus on the steepest descent and quasi-Newton method in solving unconstrained optimization problem. Therefore, we develop a new search direction for hybrid BFGS-ZMRI method with global convergence properties. Based on the numerical result, our method shows significant improvement in the number of iteration and CPU time. [ABSTRACT FROM AUTHOR]

The Rim-driven Thruster (RDT) integrates the thrust motor and the propeller, which can effectively reduce the space occupied by the propulsion system, improve the propulsion efficiency, and thus has important research value and broad market prospects. The Halbach Permanent Magnet Rim Thrust Motor (HPMRTM) can improve the torque density of the propulsion motor by utilizing the unilateral magnetic field of the Halbach array. In this paper, the numerical method is used to study the electromagnetic performance of the motor under different Halbach array parameters. The relationship between motor parameters such as air-gap flux density, electromagnetic torque and Halbach array parameters is obtained, and then the motor structure is optimized. By comparing with Common Permanent Magnet RTM, the advantages of HPMRTM are verified. [ABSTRACT FROM AUTHOR]

In this paper, the numerical analysis and computer simulation of deep drawing process has been presented. The incremental model of the process in updated Lagrangian formulation with the regard of the geometrical and physical nonlinearity has been evaluated by variational and the finite element methods. The Frederic Barlat’s model taking into consideration the anisotropy of materials in three main and six tangents directions has been used. The work out application in Ansys/Ls-Dyna program allows complex step by step analysis and prognoses: the shape, dimensions and state stress and strains of drawpiece. The paper presents the influence of selected anisotropic parameter in the Barlat’s model on the drawpiece shape, which includes: height, sheet thickness and maximum drawing force. The important factors determining the proper formation of drawpiece and the ways of their determination have been described. [ABSTRACT FROM AUTHOR]

In this paper, the authors pointed out a study on the profitable combination of forming techniques. More in detail, the attention has been put on the combination of the single point incremental forming (SPIF) and, generally, speaking, of an additional process that can lead to a material thickening on the initial blank considering the local thinning which the sheets undergo at. Focalizing the attention of the research on the excessive thinning of parts made by SPIF, a hybrid approach can be thought as a viable solution to reduce the not homogeneous thickness distribution of the sheet. In fact, the basic idea is to work on a blank previously modified by a deformation step performed, for instance, by forming, additive or subtractive processes. To evaluate the effectiveness of this hybrid solution, a FE numerical model has been defined to analyze the thickness variation on tailored sheets incrementally formed optimizing the material distribution according to the shape to be manufactured. Simulations based on the explicit formulation have been set up for the model implementation. The mechanical properties of the sheet material have been taken in literature and a frustum of cone as benchmark profile has been considered for the performed analysis. The outcomes of numerical model have been evaluated in terms of both maximum thinning and final thickness distribution. The feasibility of the proposed approach will be deeply detailed in the paper. [ABSTRACT FROM AUTHOR]

The project is the study of the thermal drilling process. The process is a hole forming process in the sheet metals using the heat generated by means of friction. The main advantage of the process over the conventional drilling process is that the holes formed using this process does not need any backing arrangements such as weld nuts, rivet nuts etc. Because the extruded bush itself acts as a supporting structure for the fasteners. This eliminates the need for the access to the backside of the work material for fastening operations. The major factors contributing the thermal drilling operation are the spindle speed and the thrust force required for forming a hole. The process of finding out the suitable thrust force and the speed for drilling a particular material with particular thickness is a tedious process. The process can be simplified by forming a mathematical model by combining the empirical formulae from the literature. These formulae were derived in the literature from the experimental trials by following certain assumptions. In this paper a suitable mathematical model is formed by replicating the experiments and tried to be validated by the results from numerical analysis. The numerical analysis of the model is done using the ANSYS software. [ABSTRACT FROM AUTHOR]

In this paper some of the important parameters that influence the effectiveness of composite material shaft of high speed rotor-bearing system on rotor dynamics are analyzed. The type of composite material composition, the number of layers along with their stacking sequences are evaluated as they play an important role in deciding the best configuration suitable for the high-speed application. In this work the lateral modal frequencies for five types of composite materials shaft of a high-speed power turbine rotor-bearing system and stresses due to operating torque are evaluated. The results are useful for the selection of right combination of material, number of layers and their stacking sequences. The numerical analysis is carried out using the ANSYS Rotor dynamic analysis features. [ABSTRACT FROM AUTHOR]

The paper presents a practical implementation of hybrid simulation using Real Time Finite Element Method (RTFEM). Hybrid simulation is a technique for investigating dynamic material and structural properties of mechanical systems by performing numerical analysis and experiment at the same time. It applies to mechanical systems with elements too difficult or impossible to model numerically. These elements are tested experimentally, while the rest of the system is simulated numerically. Data between the experiment and numerical simulation are exchanged in real time. Authors use Finite Element Method to perform the numerical simulation. The following paper presents the general algorithm for hybrid simulation using RTFEM and possible improvements of the algorithm for computation time reduction developed by the authors. The paper focuses on practical implementation of presented methods, which involves testing of a mountain bicycle frame, where the shock absorber is tested experimentally while the rest of the frame is simulated numerically. [ABSTRACT FROM AUTHOR]

Integration of stress in an RC cross-section is an important step in any computation of an RC beam or frame. In a standard procedure, the numerical integration is used in most cases. However, in 2005, Zupan & Saje developed a semi-analytical method of section stress integration [1]. This paper discusses a compact algorithm for the method published by Zupan & Saje. The compactness is achieved by splitting the computations into two parts: the first one focuses on calculating stress integrals which are independent of the section geometry and the second on generating coefficients dependent on the geometry but not on stress. In order to demonstrate the steps of the algorithm, the authors have provided a detailed example of the most frequently studied section, published by Fafitis [2]. The complete algorithm is presented in the last part of the paper. [ABSTRACT FROM AUTHOR]

The paper presents the defect detection in plates considering the influence of dynamic characteristics, especially with regard to the vibration modes. The aim if this work is to detect the localization of a defect provided that damage exists in the considered plate structure. The Kirchhoff plate bending is described and solved by the Boundary Element Method (BEM). Plates have rectangular shape and different boundary conditions. The analysis of a structural response is carried out with the use of signal processing tool namely Discrete Wavelet Transformation (DWT). Defects in plates are introduced as slots near the plate boundary. [ABSTRACT FROM AUTHOR]

The paper deals with numerical analysis of the DCB test configuration together with the data reduction scheme described in the ASTM D 5528 Standard for determination of the mode I fracture toughness in case of the laminated composites with mechanical couplings. Numerical analysis based on the FEM approach was performed with the Abaqus software exploiting the VCCT technique. The experiments on the DCB beams made of coupled laminates were also performed. The results show, that the distribution of the Strain Energy Release Rate can be asymmetric. A need for appropriate data reduction schemes has been revealed. [ABSTRACT FROM AUTHOR]

The paper considers the problem of coach occupant safety during crash events. The authors present a simple low-cost seat buffer concept which may mitigate the effects of frontal impact. The method of computer simulation was chosen to solve the problem efficiently. The Finite Element Method (FEM) implemented in the LS-DYNA commercial code was used. The testing procedure was based on European Commission regulations, under which vehicles move at a defined speed. Simulations have shown that seat occupants suffer serious trauma during a crash, with the head experiencing relatively high acceleration, thus resulting in an HIC36 of 1490. The installation of a protective buffer mounted on the upper part of the seat reduced the HIC36 to only 510. However, in its current form it does not meet the requirements of the regulations. Further modifications to the overlay shape and structure are essential in order to better improve the deceleration of passengers' bodies. Moreover, a detailed model of seats and their anchorage should be taken into account. A more flexible structure should provide more positive and more accurate results. [ABSTRACT FROM AUTHOR]

This paper presents an attempt of using a finite element method for predicting delamination of a glue laminated timber beam through a cohesive layer. There were used cohesive finite elements, quadratic stress damage initiation criterion and mixed mode energy release rate failure model. Finite element damage was equal to its complete stiffness degradation. Timber material was considered to be an orthotropic with plastic behaviour after reaching bending limit. [ABSTRACT FROM AUTHOR]

The paper considers the influence of the assumed error indicator on the final adapted mesh. Provided that threshold values of an error are increased by applying the adaptive procedure, it turns out that final mesh depends on the assumed error indicator. In the paper, there were used the standard error estimates and the error indicator proposed by the author. The proposed error indicator is based on applying hierarchically generalized finite difference method (FDM). In the case of the proposed error indicator, the final adapted mesh is the most optimal for the exact solution. [ABSTRACT FROM AUTHOR]

We present an enhancement of the multiscale finite element method (MsFEM) by combining it with the hp-adaptive FEM. Such a discretization-based homogenization technique is a versatile tool for modeling heterogeneous materials with fast oscillating elasticity coefficients. No assumption on periodicity of the domain is required. In order to avoid direct, so-called overkill mesh computations, a coarse mesh with effective stiffness matrices is used and special shape functions are constructed to account for the local heterogeneities at the micro resolution. The automatic adaptivity (hp-type at the macro resolution and h-type at the micro resolution) increases efficiency of computation. In this paper details of the modified MsFEM are presented and a numerical test performed on a Fichera corner domain is presented in order to validate the proposed approach. [ABSTRACT FROM AUTHOR]

In this paper, we study the inverse problem for the reconstruction of the right-hand side of parabolic systems of equations with overdeterminations, given by point measurements. The numerical algorithm is based on a special decomposition of the numerical solution first proposed for the heat equation in [9, 11]. Numerical experiments show the capacity of the numerical algorithm for parabolic systems. [ABSTRACT FROM AUTHOR]

The paper considers the problem of describing high-angle boundary migration within the framework of a multilevel inelastic deformation modeling approach. The proposed method is based on the consideration of grain boundary defects (grain boundary steps) and takes into account the physical mechanism of boundary migration. Steps are formed at the intersection of edge lattice dislocations with grain boundaries. The quantitative characteristic of such steps is their height, which is determined by the scalar product of the Burgers vector of a lattice dislocation with the normal of the boundary facet plane. The grain boundary migration velocity is proportional to the difference in the height of grain boundary steps of neighboring grains. Numerical calculations are carried out to confirm most of the experimental dependences between the migration velocity and orientation of boundary facets. [ABSTRACT FROM AUTHOR]

The solution of a singularly perturbed problem corresponds to a function with large gradients. Therefore the question of interpolation and numerical differentiation of such functions is relevant. The interpolation based on Lagrange polynomials on uniform mesh is widely applied. However, it is known that the use of such interpolation for the function with large gradients leads to estimates that are not uniform with respect to the perturbation parameter and therefore leads to errors of order O(1). To obtain the estimates that are uniform with respect to the perturbation parameter, we can use the polynomial interpolation on a fitted mesh like the piecewise-uniform Shishkin mesh or we can construct on uniform mesh the interpolation formula that is exact on the boundary layer components. In this paper the numerical differentiation formulas for functions with large gradients based on the interpolation formulas on the uniform mesh, which were proposed by A.I. Zadorin, are investigated. The formulas for the first and the second derivatives of the function with two or three interpolation nodes are considered. Error estimates that are uniform with respect to the perturbation parameter are obtained in the particular cases. The numerical results validating the theoretical estimates are discussed. [ABSTRACT FROM AUTHOR]

The present paper describes the applications of vortex regulators and the current state of the issue on the use and development of such devices. A patent review has been carried out. Automatic control systems using a vortex regulator are considered. Based on the analysis and preliminary numerical calculation of gas flow in the working cavity of the regulator, a new design of a vortex gas pressure regulator has been developed. An experimental sample of the device was made using additive technologies and a number of tests were carried out. The results of experimental studies confirmed the adequacy of the created mathematical model. Based on further numerical studies a new design of a vortex regulator with a distributed feed of the process control flow as well as with the regulated swirl of the supply and control process flows has been developed. [ABSTRACT FROM AUTHOR]

Recently, numerous studies have been concerned in conjugate gradient methods for solving large-scale unconstrained optimization method. In this paper, a three-term conjugate gradient method is proposed for unconstrained optimization which always satisfies sufficient descent direction and namely as Three-Term Rivaie-Mustafa-Ismail-Leong (TTRMIL). Under standard conditions, TTRMIL method is proved to be globally convergent under strong-Wolfe line search. Finally, numerical results are provided for the purpose of comparison. [ABSTRACT FROM AUTHOR]

A nonlinear conjugate gradient method (CG) plays an important role in solving a large-scale unconstrained optimization problem. This method is widely used due to its simplicity. The method is known to possess sufficient descend condition and global convergence properties. In this paper, a new nonlinear of CG coefficient βk is presented by employing the Strong Wolfe-Powell inexact line search. The newβk performance is tested based on number of iterations and central processing unit (CPU) time by using MATLAB software with Intel Core i7-3470 CPU processor. Numerical experimental results show that the newβk converge rapidly compared to other classical CG method. [ABSTRACT FROM AUTHOR]

The Laplace-Beltrami operator plays an important role as C² function smoother and its eigenfunction applications are studied extensively in last five decades, not only, in image processing field but we can meet with these functions ranging from molecular physics scientific field to mechanical engineering. However, in many non-trivial cases, e.g. computations on non-uniform meshes, the discrete Laplace operator could be ill-conditioned and inappropriate for numerical computations. Especially, in the spectral clustering tool, a condition number of the graph Laplacian goes to infinity, when pairwise similarities among most graph nodes go to zero. Therefore, in this paper, we reformulate the image graph Laplacian as the semi-smooth Laplace-Beltrami operator on a non-uniform mesh and study its numerical properties, then we introduce our fundamental approach for improving a numerical stability of this operator. [ABSTRACT FROM AUTHOR]

In this paper, a new class of time-stepping schemes for structural dynamics is presented, which originally emanate from Gauss-Runge-Kutta schemes as traditional representatives of higher-order symplectic-momentum schemes. The presented time stepping schemes belong to the family of higher-order energy-momentum schemes, which represent Gauss-Runge-Kutta schemes with a physically motivated time approximation of the considered mechanical system. As higher-order energy-momentum schemes so far are not derived by using a straight-forward design method, a variational-based design of energy-momentum schemes is shown. Here, a differential variational principle of continuum mechanics, Jourdain's principle, is discretized, and energy-momentum schemes emanate as discrete Euler-Lagrange equations. This procedure is strong related, but is not identical, to the derivation of variational integrators (VI), which emanate from discretising a Lagrange function or Hamilton's principle, respectively. Furthermore, this design procedure is well suited to connect energy-momentum schemes with numerical modifications based on mixed variational principles, as the enhanced assumed strain elements for improving the spatial discretisation in direction of a locking-free discrete formulation. Therefore, a Q1/E9 energy-momentum scheme of higher order for the continuum formulation of fiber-reinforced materials is presented. This material formulation is important for simulating dynamics of light-weight structures. [ABSTRACT FROM AUTHOR]

In this paper, we define bi-periodic Fibonacci and Lucas polynomials and investigate properties of these polynomials which generalized of bi-periodic Fibonacci and Lucas numbers. We also obtain some new algebraic properties on these numbers and polynomials. [ABSTRACT FROM AUTHOR]

The paper presents the mixed-mode delamination of plates made of sublaminates. To this purpose an opening load mode of delamination is proposed as failure model. The failure model is implemented in ANSYS code to calculate the mixed-mode delamination response as energy release rate. The analysis is based on interface techniques. Within the interface finite element modeling there are calculated the individual components of damage parameters as spring reaction forces, relative displacements and energy release rates along the lamination front. [ABSTRACT FROM AUTHOR]

The paper considers the problem of estimating the stress-strain state of a cylindrical pipe section according to measured vertical displacements of a number of cross-sections of the cylinder. The problem is ambiguous, as there are an infinite number of different variants of loading, under the action of which we obtain the same values of displacements at a finite number of the set points of the pipeline. Four variants of such loading from the hard(concentrated load) to soft (continuously distributed according to some rule) are discussed . As a model of a cylindrical pipe section is used the linear theory of thin shells. The method of orthogonal sweep Godunov is used for the numerical solution of the corresponding linear boundary-value problems. [ABSTRACT FROM AUTHOR]

This paper addresses on the numerical modeling approaches for flood inundation in urban areas. Decisive strategy to choose between 1D, 2D or even a hybrid 1D-2D model is more than important to optimize flood inundation analyses. To find cost effective yet robust and accurate model has been our priority and motivation in the absence of available High Performance Computing facilities. The application of 1D, 1D/2D and full 2D modeling approach to river flood study in Jakarta Ciliwung river basin, and a comparison of approaches benchmarked for the inundation study are presented. This study demonstrate the successful use of 1D/2D and 2D system to model Jakarta Ciliwung river basin in terms of inundation results and computational aspect. The findings of the study provide an interesting comparison between modeling approaches, HEC-RAS 1D, 1D-2D, 2D, and ANUGA when benchmarked to the Manggarai water level measurement. [ABSTRACT FROM AUTHOR]

Economic order quantity (EOQ) model has been used extensively over a century. Many studies have altered the model to imitate the actual inventory problem. This paper extends the traditional EOQ model and considers an inventory condition where items received are partly with imperfect quality and noninstantaneous deterioration after inspection. We assume the imperfect quality items are discarded immediately by the end of the 100% screening process. A mathematical model is developed and numerical examples along with graphical representation and sensitivity analysis are provided to illustrate the model. [ABSTRACT FROM AUTHOR]

In this paper, the problem of boundary layer flow and heat transfer in a viscous fluid over a stretching sheet with viscous dissipation and internal heat generation is studied. Thermal boundary condition on the surface that is prescribed surface temperature (PST) is considered. The governing nonlinear partial differential equations are transformed into nonlinear ordinary differential equations by applying the similarity transformations. The obtained nonlinear ordinary differential equations are reduced to the system of first order ordinary differential equations. Then the system of first order ordinary differential equations is solved numerically using the Keller-box method. Results are presented in figures and discussed in details for the temperature profiles and the temperature gradient for some values of the Prandtl number, Eckert number and heat/source sink parameter. [ABSTRACT FROM AUTHOR]

In this paper, flow and heat transfer over a stretching and shrinking sheet with slip and convective boundary condition were investigated. The governing boundary layer equations are transformed into ordinary differential equations and solved by using the shooting technique. The stretching and shrinking parameters, dimensionless slip parameter, Biot number and constant mass suction parameter are used to generate the numerical results. The results show that the dual solutions exist for suction case. The obtained results also indicate that the mass suction and slip processes delay the boundary layer separation. [ABSTRACT FROM AUTHOR]

Intraguild Predation (IGP) is classified as killing and eating among potential competitors. Intraguild Predation is a universal interaction, differing from competition or predation. Lotka Volterra competition model and Intraguild predation model has been analyze. The assumption for this model is no any immigration or migration involves. This paper is only considered IGP model for susceptible and infective (SI) only. The analysis of stability of the equilibrium points of Intraguild Predation Models with disease using Routh Hurwitz criteria will be illustrated using some numerical example. [ABSTRACT FROM AUTHOR]

Many soft robotic structures are developed using soft fluidic actuators, which are developed using elastomeric materials such as silicon rubber. Due to the complicated geometries and nonlinearity in the soft actuator's design, it becomes very difficult to predict their behavior analytically. Finite Element Method (FEM) analysis is a numerical technique which is utilized to predict the stress, strain, and deformation in such actuators design. In this paper, bending behavior of two soft pneumatic fingers with varying wall thickness are designed and compared. Bending angle configurations of the designed fingers are evaluated at 30 and 40 kPa of actuating pressure. The obtained results show that to achieve a bending angle of 116 degrees, finger 2 requires 40 kPa of actuating pressure whereas finger 1 requires 80 kPa. Due to low stiffness of finger 2 as compared to the finger 1, which is resulted due to thickness variation in the two designed fingers, much higher bending angle configuration can be achieved at very low pressure for the finger 2. [ABSTRACT FROM AUTHOR]

The presence of ducts surrounding wind turbines improves the performance by accelerating the wind at the entrance. The objective is to find a duct that produces improved wind power with low duct drag forces. Numerical analyses were carried out on the flow past a ducted wind turbine using computational software ANSYS Fluent. In this paper, the performance of six different ducts surrounding the wind turbine was compared. The duct geometries considered were S1) E423 aerofoil duct of chord length (L) / (throat diameter) D ratio=0.225 at 37.5 °, S2) duct with leading-edge slot, S3) duct with trailing edge slot, S4) duct with trailing edge flap, S5) duct with converging section and S6) duct with multiple slots. The performance improvement was evaluated using the average velocity in front of the blade plane and power output. The flow characteristics of conventional turbines and six ducted turbines were discussed. It was found that duct with trailing edge flap had shown higher power output with higher drag. The results indicate that the duct with multiple slots in the duct's circumference had equivalent power output to a fully closed duct. [ABSTRACT FROM AUTHOR]

A screw-type centrifugal pump is a kind of non-clog type pump and has been widely used, for instance, for drainage of rainwater as well as slurries and mud in sewage control systems. In order to avoid choking the impeller passage with the congestion of solids, the impeller is designed to have a wide passage which configuration is screw formed by a three-dimensional spiral blade added to a conical hub cone. This paper presents the results of pressure and velocity fields in centrifugal pump with single blade. In the pump tested, a volute with circular cross-section was used. The prediction of radial thrust is important and useful information for the safe operation and design of the bearings. Particularly, the fluctuation of radial thrust in this pump is large because of one blade. The tests were carried out for several flows, including above and below the nominal one. Effects of the time-steady flow in a single-blade pump are investigated by numerical method CFD (Computational Fluid Dynamics), specifically discussing the conditions of internal flow such as velocity and pressure. For a numerical approach the three-dimensional, viscous, unsteady flow field in the pump has been achieved by solving the unsteady Navier-Stokes equations (URANS) with a commercial code. Commercial code ANSYS CFX was used for the calculations. [ABSTRACT FROM AUTHOR]

In March 2021, an ultra-large container ship, the M.V Ever Given, was stranded at the southern part of the Suez Canal and blocked the two ways of the canal and subsequently deferred more than 100 vessels traversing between Asia and Europe. The blockage was cleared within five days; however, notwithstanding the short period, the incident had caused huge world trade losses. One of the prevailing causes of ship groundings is manoeuvring difficulties due to ship-bank interaction. This study is therefore aimed at understanding the effect of the ship's size on the ship-bank interaction in a canal. In this paper, a mathematical model was developed to study the effects of ship-bank interaction on the manoeuvring performance of a large container vessel in a canal, with different ship parameters. The results showed that the increase in size and speed significantly influenced the bank-effect and contributed to the eventual grounding of the ship. The effect of rudder surface area to counter the bank-effect was also investigated. This study showed that increasing the rudder surface area can improve the counter-actions of the ship against the bank effect. [ABSTRACT FROM AUTHOR]

The ship hull is the basic underlying structure of ship that makes the ship water tight or water proof. Meaning the hull prevents the water from entering the cargo, machinery.so hull are usually made of materials that have high mechanical properties, impact less and less water absorption qualities.conventional hull materials used where steel wherein the boat becomes too heavy in considerations with its high strength, abrasion resistance etc.so composite materials where used which give a single structure offering solutions of strength, durability, light speedy, watertight structure in the manufacturing of boats for past 50 years. This novel paper focuses on a comparative study of composite materials previously used with further improvements in characteristics such as increased strength, ease of manufacturing, more impact resistance and increase is load tensile and compressive load bearing characteristics. The composite materials comprising of GFRP+graphite powder and GFRP+Aluminum powder was tested and analyzed experimentally for enhancement in various mechanical properties, structural and water absorption capabilities, and optimum designs further obtained. Even though experimental analysis where performed numerical analysis of these composite models is yet to done which would lead to determining more efficient structures with best materials used. [ABSTRACT FROM AUTHOR]

Investigation still on board for finding the best techniques to develop the thermal and hydraulic performance of the heat exchanger. One of the useful, practical methods for finding the modification is the numerical analysis. This numerical analysis was obtained by modelling and simulation using ANSYS FLUENT software. In this present work five elements were modelled and simulated of three different configuration models, helical tape, rectangular and triangular straight strip inserts were inserted inside the inner pipe. This simulation was employed according to the working operation conditions of the real practical double pipe heat exchanger. The results show that, the helical tape configuration demonstrated the effective enhancing technique of the heat transfer, which is improving the thermo-hydraulic performance of this type of heat exchanger in this study. According to this work, the technique of studying numerically the design enhancement of the heat exchanger can produce an excellent result and gives a good recommendation to transfer it into practical work. [ABSTRACT FROM AUTHOR]

: Tilt of G+4 RCC buildings with isolated foundation systems due to differential settlement is one of the common problems, which affects the overall structural stability of the real life buildings. Tilt may be caused due to excavation of adjacent plots of the building without adequate lateral support, poor workmanship, overloading on cantilevered portions above first floor level, improper design and construction etc. The overall stability of the tilted RCC buildings mainly depend on the type & amount of tilt along with the building configuration. NDT results of concrete members are nowadays practiced extensively in real life situation to evaluate the strength and quality; which are sparse to assess the stability of the structures as these are of qualitative and piecewise manner. Additionally, the seismic force; which depends on the seismic zone of the building site, adversely affects the building stability. Thus, the parametric study on the stability of various buildings subjected to different type & extent of tilts; situated on different seismic zones seems to be significantly important. This present paper aims to assess the stability of various G+4 RCC buildings of same plan area & height, with different number of bays in their structural system, located at different seismic zones; when subjected to different extent of uniaxial and biaxial tilts. Different G+4 RCC buildings with different structural configurations and located at different seismic zones; subjected to different types & amount of tilt are duly considered in the finite element framework of SAP2000 for the parametric numerical analyses. Along with type & extent of tilt, it is found that building configuration and zone of seismicity significantly affects the overall stability of these multistoried tilted buildings. The present study may have a great scope for safety assessment and upgradation of real life medium high RCC building structures subjected to tilt. [ABSTRACT FROM AUTHOR]

Advanced high strength steel is the basic structure material for lightweight design and safety enhancement for automobile industry. Quenching and partitioning steel is a recently developed kind of low carbon and low alloy material with retained Austenite for the requirements of both high strength and high ductility. This paper focuses on the formability of a hinge pillar for some car under numerical modelling analysis. The results show that QP980 has an equal elongation comparing with DP590. Moreover, the numerical modelling results of QP980 are more sensitive to the selection of yielding equation comparing with DP590. [ABSTRACT FROM AUTHOR]

In this paper, a fourth-order explicit hybrid method with constant step-size is developed. The free parameters are chosen so that the error constant is small. Numerical comparisons are carried out to show the advantage of the new method for solving special second order ordinary differential equations. [ABSTRACT FROM AUTHOR]

The arrival of hardware accelerators has created a new gold rush to be the first to deliver their promise of high performance for numerical applications. Despite the recent advances in programmability, it is still hard to develop tuned programs that extract all the potential performance promised by the manufacturers. In this paper we remind the community that while this development effort is a noble endeavor, there is a lot of low hanging fruit that can be harvested easily. Picking this low hanging fruit benefits the scientific computing community immediately and prototypes the approach that further optimizations may follow. We demonstrate this by focusing on a widely used set of operations, the level-3 BLAS, targeting the NVIDIA GPUs. [ABSTRACT FROM AUTHOR]

In this paper, the influence of non-equilibrium CO2 kinetics on gas dynamic parameters and transport properties in a viscous shock layer near blunt bodies is studied. This problem is important for accurate prediction of macroscopic parameters and heat transfer near a space vehicle re-entering the Mars atmosphere. The hypersonic flow of reacting CO2/CO/O2/C/O mixture is studied numerically using the accurate kinetic theory models for transport properties and chemical reaction rates proposed in our previous papers on the basis of three-temperature vibrational distributions. The kinetic theory algorithms were implemented directly to the computational fluid dynamics solvers. The transport properties and gas dynamic parameters in 2-D viscous shock layer near blunt bodies of different shape are studied for various test cases under Mars re-entry conditions. The influence of non-equilibrium effects on gas flow parameters and heat transfer is discussed; a quite different structure of a shock layer is found for various body shapes. The comparison with the results obtained using more simple models for CO2 kinetics, transport coefficients, and reaction rates is shown. [ABSTRACT FROM AUTHOR]

In this paper we present and discuss some new developments of Hardy-type inequalities, namely to derive (a) Hardy-type inequalities via a convexity approach, (b) refined scales of Hardy-type inequalities with other 'breaking points' than p = 1 via superquadratic and superterzatic functions, (c) scales of conditions to characterize modern forms of weighted Hardy-type inequalities. [ABSTRACT FROM AUTHOR]