Direct fluid–structure coupling analysis of reciprocating series seals in hydropneumatic suspension

2019 ◽  
Vol 234 (6) ◽  
pp. 932-946
Author(s):  
Shouyuan Zhang
Keyword(s):  
Friction Force ◽  
High Efficiency ◽  
Hydrodynamic Lubrication ◽  
Fluid Velocity ◽  
Three Dimensional ◽  
Axial Direction ◽  
Coupling Model ◽  
Element Discretization ◽  
Fluid Structure ◽  
Sealing Performance

The reciprocating piston seals are crucial parts in hydraulic system, which are widely used in aerospace and military industry. A direct fluid–structure coupling method with high efficiency is proposed for solving the transient Elaso-Hydrodynamic-Lubrication problem in float piston series seal system of hydropneumatic suspension. The method is validated by theory solution of a simple pad-bearing film model. Detailed three-dimensional fluid–structure coupling model of the seal system is built using finite element discretization. Rubber material tests are carried out to obtain parameters of the third-order Ogden constitutive model for the O-ring seal. The sealing performance and friction force of the complicated series seal system are analyzed with direct fluid–structure dynamic coupling simulation in high pressure and high speeds conditions. The critical speed from mixed lubrication to full film lubrication is obtained. The fluid velocity and pressure distribution in the sealing gap along axial direction is compared. The outlet volume flux leakage in different piston speeds and inlet pressures is calculated to evaluate the sealing performance. The friction force experiment for the float piston system is carried out in various speeds. The friction force from direct fluid–structure interface simulation coincides well with the test result.

scholarly journals Significance of Nonsimilar Numerical Simulations in Forced Convection from Stretching Cylinder Subjected to External Magnetized Flow of Sisko Fluid

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Jifeng Cui ◽  
Umer Farooq ◽  
Ahmed Jan ◽  
Murtada K. Elbashir ◽  
Waseem Asghar Khan ◽  
...  
Keyword(s):  
Circular Cylinder ◽  
Frictional Heating ◽  
Fluid Velocity ◽  
Axisymmetric Flow ◽  
Three Dimensional ◽  
Axial Direction ◽  
High Viscosity ◽  
Heat Equations ◽  
Dimensionless Numbers ◽  
Sisko Fluid

The practice of flowing effort is participating in various industries especially in nutrition productions all around the world. These fluids practices are utilized extensively in nutrition handling productions by making use of sticky liquids to produce valuable food manufactured goods in bulk. Nevertheless, such productions ought to guarantee that involved equipment such as pipelines are maintained clean as well as are cleared out for the efficient movement of fluids. The nonsimilar characteristics of involuntary convection from circular cylinder stretching in the axial direction subjected to an external flow of Sisko fluid characterized by the freely growing boundary layers (BL) are presented in this research. A circular cylinder is submerged in a stationary fluid. The axial stretching of the cylinder causes external fluid flow. The magnetic force of strength ″ B 0 ″ is enforced in the transverse direction. Because of the fluid's high viscosity, frictional heating due to viscous dissipation is quite significant. The flow is three dimensional but with no circumferential variations. The governing equations for axisymmetric flow that include the mass balance, x -momentum, and heat equation are modeled through conservation laws. The dimensionless system is developed by employing appropriate nonsimilar transformations. The numerical analyses are presented by adapting local nonsimilarity via finite-difference (FDM)-based MATLAB algorithm bvp4c. The characteristics of dimensionless numbers are determined by graphs that are plotted on momentum and heat equations. The nonsimilar simulations have been compared with the existing local similar solutions. Fluid velocity is increased as the material and curvature parameters are increased, resulting in improved heat transfer. The deviation in skin friction and local Nusselt number against the various dimensionless numbers is also analyzed.

Consistent Asymptotic Expansion Multiscale Formulation for Heterogeneous Column Structure

2012 ◽  
Vol 134 (3) ◽  
Author(s):  
Dongdong Wang ◽  
Pinkang Xie ◽  
Lingming Fang
Keyword(s):  
Asymptotic Expansion ◽  
Displacement Field ◽  
Three Dimensional ◽  
Axial Direction ◽  
Unit Cell ◽  
Local Unit ◽  
Cell Problem ◽  
Element Discretization ◽  
Free Condition ◽  
Column Structure

A consistent asymptotic expansion multiscale formulation is presented for analysis of the heterogeneous column structure, which has three dimensional periodic reinforcements along the axial direction. The proposed formulation is based upon a new asymptotic expansion of the displacement field. This new multiscale displacement expansion has a three dimensional form, more specifically, it takes into account the axial periodic property but simultaneously keeps the cross section dimensions in the global scale. Thus, this formulation inherently reflects the characteristics of the column structure, i.e., the traction free condition on the circumferential surfaces. Subsequently, the global equilibrium problem and the local unit cell problem are consistently derived based upon the proposed asymptotic displacement field. It turns out that the global homogenized problem is the standard axial equilibrium equation, while the local unit cell problem is completely three dimensional which is subjected to the periodic boundary condition on axial surfaces as well as the traction free condition on circumferential surfaces of the unit cell. Thereafter, the variational formulation and finite element discretization of the unit cell problem are discussed. The effectiveness of the present formulation is illustrated by several numerical examples.

scholarly journals The non-Newtonian maxwell nanofluid flow between two parallel rotating disks under the effects of magnetic field

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Ali Ahmadian ◽  
Muhammad Bilal ◽  
Muhammad Altaf Khan ◽  
Muhammad Imran Asjad
Keyword(s):  
Magnetic Field ◽  
Thermal Conductivity ◽  
Brownian Motion ◽  
Flow Behavior ◽  
Fluid Velocity ◽  
Three Dimensional ◽  
Axial Direction ◽  
Rotating Disks ◽  
Physical Constraints ◽  
Fourth Order Method

Abstract The main feature of the present numerical model is to explore the behavior of Maxwell nanoliquid moving within two horizontal rotating disks. The disks are stretchable and subjected to a magnetic field in axial direction. The time dependent characteristics of thermal conductivity have been considered to scrutinize the heat transfer phenomena. The thermophoresis and Brownian motion features of nanoliquid are studied with Buongiorno model. The lower and upper disk's rotation for both the cases, same direction as well as opposite direction of rotation is investigated. The subsequent arrangement of the three dimensional Navier Stoke’s equations along with energy, mass and Maxwell equations are diminished to a dimensionless system of equations through the Von Karman’s similarity framework. The comparative numerical arrangement of modeled equations is further set up by built-in numerical scheme “boundary value solver” (Bvp4c) and Runge Kutta fourth order method (RK4). The various physical constraints, such as Prandtl number, thermal conductivity, magnetic field, thermal radiation, time relaxation, Brownian motion and thermophoresis parameters and their impact are presented and discussed briefly for velocity, temperature, concentration and magnetic strength profiles. In the present analysis, some vital characteristics such as Nusselt and Sherwood numbers are considered for physical and numerical investigation. The outcomes concluded that the disk stretching action opposing the flow behavior. With the increases of magnetic field parameter $$M$$ M the fluid velocity decreases, while improving its temperature. We show a good agreement of the present work by comparing with those published in literature.

Friction characteristics of sliding guideway material considering original surface functional parameters under hydrodynamic lubrication

2016 ◽  
Vol 231 (7) ◽  
pp. 813-825 ◽  
Author(s):  
Bin Zhao ◽  
Song Zhang ◽  
Jianfeng Li ◽  
Peng Wang
Keyword(s):  
Friction Force ◽  
Failure Modes ◽  
Hydrodynamic Lubrication ◽  
Three Dimensional ◽  
Dynamics Simulation ◽  
Surface Model ◽  
Functional Surface ◽  
Transform Method ◽  
Surface Parameters ◽  
Dimensional Surface

The most common failure modes for guideway are wear and contact fatigue, which are significantly influenced by the friction properties of the contact surfaces. In this paper, three-dimensional surface parameters of surface roughness are investigated to evaluate guideway surface. First, an effective three-dimensional surface model is achieved using wavelet transform method and a reverse engineering software (Geomagic Studio). Secondly, effects of the functional surface parameters on friction force, mean pressure, and friction coefficient are studied using the computational fluid dynamics simulation method, and a regression model to predict friction force is achieved. Thirdly, the optimal surface parameters combinations are analyzed looking at friction property index, and the simulation results are compared. Finally, a verification test is conducted to detect the validity of the simulation research. The results show a good agreement between the experimental results and simulations. This study provides theoretical guidance for the manufacture of guideway.

Research on the motion law of fiber in the vortex field inside the nozzle based on ADINA fluid–structure coupling model

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Chenchen Han ◽  
Weidong Gao
Keyword(s):  
Air Flow ◽  
Three Dimensional ◽  
Coupling Model ◽  
Calculation Model ◽  
Air Pressure ◽  
Two Phase ◽  
Fluid Structure ◽  
Content Type ◽  
Air Jet ◽  
Vortex Field

PurposeThe purpose of the paper is researching on the motion law of fiber in the vortex field inside the nozzle.Design/methodology/approachA three-dimensional calculation model was established using the MVS861 (Muratec Vortex Spinning) air-jet vortex-spinning nozzle as the prototype, and the fluid–solid coupling calculation module in the finite element calculation software ADINA (Adina System) was used to numerically analyze the fiber-air flow two-phase coupling. At the same time, the effect of the air pressure at the nozzle on the two-phase flow is studied.FindingsThe results show that after the air flow ejected through the nozzle, a vortex field will be generated in the flow field to push the internal fiber to move toward the nozzle outlet in a wave motion; as the air pressure at the nozzle increases, the fiber movement period becomes shorter and the oscillation frequency becomes higher; increasing the air pressure at the spray hole can improve the working efficiency of fiber twisting and wrapping.Originality/valueThe research present an effective and feasible theoretical model and method for the motion law of fiber in the vortex field inside the nozzle based on ADINA fluid–structure coupling model.

Comparison with Thermo Hydrodynamic Lubrication between 2D and 3D Model in Thrust Bearing by Computing Simulation

2010 ◽  
Vol 129-131 ◽  
pp. 1336-1340
Author(s):  
Zhi Lan Chen ◽  
Jun Zhu
Keyword(s):  
3D Model ◽  
Thrust Bearing ◽  
Hydrodynamic Lubrication ◽  
Three Dimensional ◽  
Axial Direction ◽  
Maximum Temperature ◽  
Interface Problem ◽  
Oil Film ◽  
Lubrication Performance ◽  
Calculated Model

As the interface problem of discontinuity boundary condition between the oil film and the pad in thrust bearing, a conjugated solution method by using the temperature continuity and the heat flux continue is proposed. The three-dimensional calculated model of thrust bearing is constructed and solved by using finite difference method. Comparing with 2D model, the characteristics of the lubrication performance of 3D model are more different. The results show that the three-dimensional calculated model not only revealed the relation of temperature variation between the oil film layer and the pad in axial direction, but also exactly reflected real temperature distribution in the pad surface. In the same oil feed temperature condition, the minimum film thickness is 63.8μm and the maximum temperature on the pad surface reached 55°C for 3D mode, 72.6μm and 60°C for 2D mode.

Finite Element Modeling for Steel Cord Analysis in Radial Tires

2013 ◽  
Vol 41 (1) ◽  
pp. 60-79 ◽  
Author(s):  
Wei Yintao ◽  
Luo Yiwen ◽  
Miao Yiming ◽  
Chai Delong ◽  
Feng Xijin
Keyword(s):  
Finite Element ◽  
High Efficiency ◽  
Force Measurement ◽  
Three Dimensional ◽  
Local Stress ◽  
Tension Force ◽  
Center Line ◽  
Element Analysis ◽  
Design Variables ◽  
Steel Cord

ABSTRACT: This article focuses on steel cord deformation and force investigation within heavy-duty radial tires. Typical bending deformation and tension force distributions of steel reinforcement within a truck bus radial (TBR) tire have been obtained, and they provide useful input for the local scale modeling of the steel cord. The three-dimensional carpet plots of the cord force distribution within a TBR tire are presented. The carcass-bending curvature is derived from the deformation of the carcass center line. A high-efficiency modeling approach for layered multistrand cord structures has been developed that uses cord design variables such as lay angle, lay length, and radius of the strand center line as input. Several types of steel cord have been modeled using the developed method as an example. The pure tension for two cords and the combined tension bending under various loading conditions relevant to tire deformation have been simulated by a finite element analysis (FEA). Good agreement has been found between experimental and FEA-determined tension force-displacement curves, and the characteristic structural and plastic deformation phases have been revealed by the FE simulation. Furthermore, some interesting local stress and deformation patterns under combined tension and bending are found that have not been previously reported. In addition, an experimental cord force measurement approach is included in this article.

scholarly journals Construction of the Cellulose Nanofibers (CNFs) Aerogel Loading TiO2 NPs and Its Application in Disposal of Organic Pollutants

Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1841
Author(s):  
Kang Li ◽  
Xuejie Zhang ◽  
Yan Qin ◽  
Ying Li
Keyword(s):  
High Efficiency ◽  
Sol Gel ◽  
Cellulose Nanofibers ◽  
Three Dimensional ◽  
Good Mechanical Property ◽  
Polar Groups ◽  
Dimensional Network ◽  
Natural Polysaccharide ◽  
Valuable Method ◽  
Adsorption Capability

Aerogels have been widely used in the adsorption of pollutants because of their large specific surface area. As an environmentally friendly natural polysaccharide, cellulose is a good candidate for the preparation of aerogels due to its wide sources and abundant polar groups. In this paper, an approach to construct cellulose nanofibers aerogels with both the good mechanical property and the high pollutants adsorption capability through chemical crosslinking was explored. On this basis, TiO2 nanoparticles were loaded on the aerogel through the sol-gel method followed by the hydrothermal method, thereby the enriched pollutants in the aerogel could be degraded synchronously. The chemical cross-linker not only helps build the three-dimensional network structure of aerogels, but also provides loading sites for TiO2. The degradation efficiency of pollutants by the TiO2@CNF Aerogel can reach more than 90% after 4 h, and the efficiency is still more than 70% after five cycles. The prepared TiO2@CNF Aerogels have high potential in the field of environmental management, because of the high efficiency of treating organic pollutes and the sustainability of the materials. The work also provides a choice for the functional utilization of cellulose, offering a valuable method to utilize the large amount of cellulose in nature.

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