Inner Surface Of Cylinder Research Articles

CALCULATION AND EXPERIMENTAL JUSTIFICATION OF DESIGN AND TECHNOLOGICAL SO-LUTIONS OF POWER HYDRAULIC CYLINDER ELEMENTS

The paper describes studies of the stress-strain state of power hydraulic cylinders elements. Geometric dimensions of casing and properties of materials are chosen as varied parameters. The controlled values are the levels of stresses and displacements. The criteria are weight, strength and rigidity. These characteristics determine the technical characteristics of power hydraulic cylinders. Dependences of criterion characteristics on varied parameters are established. On this basis, recommendations for substantiation of design and technological solutions of power hydraulic cylinders elements are developed. This made it possible to develop a project and technology for the manufacture of power cylinders with low material consumption. In addition, increased efficiency is provided due to the use of antifriction coating on the inner surface of cylinder. The stress level in the main material of cylinder body is limited. The strength of the area of the brazed joint material and the plastic lining layer is also ensured. A special configuration of the sealing ring is used to reduce the level of losses in the movable connection of the piston with the hydraulic cylinder body. At the same time radial displacements of the cylinder body provide acceptable contact of the moving and fixed parts of the hydraulic cylinder. In general, balanced design and technological solutions of power hydraulic cylinders elements are substantiated. They provide high technical characteristics of power hydraulic cylinders. It also increases the technological level of their production and reduces the total cost. Power hydraulic cylinders with reasonable parameters are used in the elements of technological systems. Keywords: hydraulic cylinder; finite element method; stress-strain state; computational-experimental justification

Resistance law dependence on radius ratios for turbulent Taylor-Couette flow from extended local balance model

Turbulent Couette-Taylor flow is the most interesting kind of flow for theoreticians and experimenters. There are a great number of theories and experiments for larger and larger Reynolds numbers. The picture becomes more complex if we consider the case of independently rotating cylinders. The most simple quantity is a torque, acting on the lateral surface of inner cylinder by rotating fluid. How can we deduce theoretically the torque from Navier-Stokes equation? Unfortunately we have only bounds on this variable yet. So we cause use models of turbulence to predict the torque dependence on Reynolds numbers or Taylor number and on radius ration. Here we present the results of simple calculations, based on extended local balance model. The study compares the theory with experiments.

FINDING THE TRAJECTORYOF MOVEMENT OF A MATERIAL PARTICLE ON THE INNER SURFACE OF A VERTICAL CYLINDER AT THE SIDE SUPPLY OF MATERIAL

The movement of material particles on the inner surface of the cylinder takes place in cyclones. Due to the complexity of the aerodynamics of the process, theoretical developments can not be used as a basis for calculating the design and efficiency of their operation. Because of this, a number of simplifications are allowed in the theoretical provisions, as a result of which the calculated data do not coincide with the experimental data. The use of modern software products, which have great graphics capabilities, allows you to get new results in solving such problems in the form of high-quality graphic illustrations. The aim of the study is to determine the motion of a material particle that enters the inner surface of a vertical cylinder with a given initial velocity. A number of simplifications were introduced in the calculations: air resistance, the effect of particles on each other, their size, etc. were not taken into account. Accompanying Frenet and Darboux triangles were used to find the trajectory. Differential equations of motion of a material particle on the inner surface of a vertical cylinder are compiled. The equations are solved using the MatLab system. It is established that the velocity of particles that fall on the inner surface of the cylinder decreases to a certain value, and then begins to increase. For specific conditions (coefficient of friction and radius of the cylinder), the value of the minimum speed to which the movement of particles is slowed down is approximately the same and does not depend on the value of the initial speed. This means that there is a minimum value of the initial velocity at which the particle will not slow down when it hits the surface of the cylinder. Since particles with different coefficients of friction at the initial stage of their movement on the cylinder are poorly scattered on its surface, for the effective operation of the cyclone you need to make an inlet window of sufficient size in the vertical direction.

Fatigue Failure Analyses of Three Gas Cylinders of Long-Tube Trailers

Three cylinders of a long-tube trailer leaked during an inspection and typical quality test. Thus, failure analysis was performed to determine the cause of failure. Macroscopic observation, metallographic analysis, and fracture analysis were implemented. Cylinder 1 was found leaking during the inspection. The crack was from the inner to the outer surface of the wall, and stripes from tool marks were found on the inner surface. Metallographic analysis proved that the fatigue crack originated from the tool marks in cylinder 1. Cylinders 2 and 3, which are fiber-reinforced, failed during the typical quality test, with life of approximately 13,000 cycles. The inner surface of cylinder 2 had many folds, and the fatigue crack intensified from these folds. The folds were formed by the shot blasting treatment of the cylinder. The crack of cylinder 3 was found in the position of the cylinder bottle shoulder. The inclusion on the cylinder shoulder was observed, and that on the subsurface could move to the inner surface during the hot spinning process and propagate gradually under cyclic load. The three fatigue failure analyses showed that quality examination is important during the process of cylinder production.

Characteristics of Material Removal on Micro Processing for Inner Surface of Cylinder Utilizing a Magnetic Compound Fluid

Characteristics of Material Removal on Micro Processing for Inner Surface of Cylinder Utilizing a Magnetic Compound Fluid

High Efficiency of Precision Processing for Inner Surface of Cylinder Utilizing a Magnetic Compound Fluid under an Electric Field

High Efficiency of Precision Processing for Inner Surface of Cylinder Utilizing a Magnetic Compound Fluid under an Electric Field

Effect of Different Atomization Gases on the Properties of Cylinder Bore Coatings

Oxidation during coating deposition by means of thermal spraying is a widely investigated and discussed topic. Most of the studies dealing with this subject report negative influences of oxidation on the coating properties, especially with respect to corrosion behavior. On the other hand, positive effects are reported as well, especially with regard to tribological behavior. Within this study, the oxidation phenomena in Plasma Transferred Wire Arc (PTWA) spraying process is investigated in detail. This technology is primarily used to apply coatings on the inner surface of cylinder bores in combustion engines. It is shown that the oxidation can be suppressed effectively by utilizing an alternative atomization gas like nitrogen instead of compressed air without the need of any additional torch modification. Besides the oxidation behavior, further effects depending on the used atomization gas are observed, which influence the properties of the coatings. Significantly higher hardness values are measured for the coatings deposited with nitrogen. This is traced back to different impact and cooling conditions as well as chemical interactions of the in‐flight particles with the ambient atmosphere.

Role of magnetic field on mixed convective flow between two concentric microtubes with heat generation/absorption: An exact solution

This study examines the role of magnetic field on fully developed mixed convection flow of heat generating/absorbing fluid in a vertical micro-concentric annulus with velocity slip and temperature jump at the surfaces of the cylinders. Exact solution of momentum and energy equations are obtained separately in terms of Bessel’s function and modified Bessel’s function of first and second kind. The solutions obtained are graphically represented and the effects of pertinent parameters on flow formation and skin-friction are investigated in details. Results show that the role of magnetic field is to decrease fluid velocity as well as skin-friction at the outer surface of inner cylinder. In addition, reverse flow formation can be controlled by increasing magnetic field strength.

Role of radial magnetic field on heat transfer in MHD Couette flow in an annulus with viscous and Joule dissipation

This paper presents an analytical investigation of steady, fully developed MHD Couette flow of viscous, incompressible, electrically conducting fluid in the presence of radial magnetic field. Exact solutions are derived for the governing energy and momentum equations by taking into account the effects of viscous and Joule dissipations under relevant boundary conditions. The solutions obtained are graphically represented and the effects of various controlling parameters such as Hartmann number and Brinkman number on the temperature profile and consequently the Nusselt numbers are discussed. The significant result from the study is that increase in Hartmann number leads to enhancement on the Nusselt number at outer surface of inner cylinder while the role of Hartmann number is just reverse on Nusselt number at inner surface of outer cylinder. In addition, the Brinkman number has an insignificant effect on the Nusselt numbers when both surfaces are kept at equal temperature.

Transient natural convection flow between vertical concentric cylinders heated/cooled asymmetrically

This paper investigates the impact of asymmetric heating or cooling of cylinder surfaces on transient natural convection flow in between vertical concentric cylinders. The outer surface of inner cylinder is assumed to be heated with temperature greater than the cooled inner surface of the outer cylinder. Closed form expressions are obtained by using the well-known Laplace transform technique to solve the governing partial differential equations in Laplace domain, whereas the Riemann-sum approximation is used to invert to time domain. Results show that the role of buoyancy force distribution parameter is to increase temperature, velocity, skin-friction and volume flow rate for both air and water. Further, reverse flow formation can be controlled by using suitable buoyancy force distribution parameter.

Evaluation of engine performance and effect on material of engine hardware due to prolonged use of neat Jatropha oil and their blends in indirect injection diesel engines

In present era of extensive requirement of energy for domestic, agricultural and industrial applications it is pertinent to search for the alternate fuel. There is lots of research going on in this direction. It has been reported that the Jatropha oil and blends of Jatropha oil with diesel is a potential source of such alternate fuel to produce energy. Whereas the use of such alternate fuel is examined, it is also equally important to study the effect of utilization of such fuel on engine hardware. In this research work the engine has been operated with Jatropha oil and the blend of Jatropha oil & diesel and endurance test has been carried out. It has been found that the injectors were getting choked under prolonged use when the Jatropha oil was used in large quantity. However the use of Jatropha oil to extent of 50% diesel did not exhibit such problem in injector. Also, the dimensional measurements were carried out before and after the test. It was observed that the wear on inner surface of cylinder was uneven and the traces of pitting of material took place. The pitting of material was observed on piston head and inner surface of cylinder head also. The metallic particles were observed during Tribological study through engine oil analysis.In this investigation five numbers of self governed indirect injection (IDI) diesel engines were used. The test fuel used were Diesel, 10%, 20%, 50% and 100% Jatropha oil . The long term engine endurance test as per IS: 10000 (part IX) – 1980 on five numbers of IDI diesel engines was carried out. The results of Tribological analysis (wear and tear) with 100% Jatropha oil showed comparatively less wear and tear over the entire range of endurance test. The brake thermal efficiency was observed maximum with diesel fuel and hence the specific fuel consumption was observed minimum. The overall emission characteristics were found to be best for the case of engine fuelled with diesel over the entire range of long term endurance test.

Transient Natural Convection in an Annulus with Thermal Radiation

The interaction of transient fully developed natural convection flow with thermal radiation inside a vertical annulus is analyzed both analytically and numerically. The Rosseland approximation is used to describe the radiative heat flux in the energy equation. The mathematical model capturing the present physical situation is highly non-linear due to the presence of radiation effect. The solution of transient model is obtained by implicit finite difference method. To check accuracy of the numerical solution, steady state solution for energy and momentum equations are derived analytically using perturbation series method. Skin-friction and Nusselt number at the outer surface of inner cylinder as well as inner surface of the outer cylinder are obtained. Selected sets of graphical results illustrating the effects of various controlling parameters involved in the problem on flow formation are discussed.

高温・高速ガス流のもとで付着した火山灰堆積挙動と灰付着に対する損傷評価

Japan has a special feature that there are a lot of natural disasters compared with other country. The volcanic explosion which has occurred at the Ontake-mountain in 2012 was enormous. Recently, the volcanic explosion at Mt. Fuji has been paid attention. If Mt. Fuji is exploded, it is expected that automotive engine inhales aerosol-like volcanic ash and its ash deposits on the inner surface of cylinder, and also the breaking performance could be decreased by the volcanic ash deposited on the surface of the break disk, which will bring about a traffic confusion in the whole Kanto area. As other serious problem, the site of all land-based gas turbines utilized as power generator is mainly concentrated in Tokyo bay. If the volcanic ash falls down and is inhaled in the air intake, all generators would be stopped and a blackout would be occurred finally. It is needed that such trouble related with the volcanic explosion is prevented in advance. In this study, the volcanic ash deposit simulator, which can impact and deposit aerosol-like volcanic ash under a high-temperature and high-speed gas flow, is developed in order to identify volcanic ash deposition criterion. Here, the deposition behavior on Type 304 stainless steel plate-shaped sample is examined by changing gas pressure, gas temperature and substrate temperature condition. The ash-deposited plate is also exposed at a high-temperature in order to clarify how volcanic ash attacks the structural part.

A novel plating apparatus for electrodeposition of Ni-SiC composite coatings using circulating-solution co-deposition technique

An innovative composite plating apparatus for complex-shaped cylinders has been proposed. It allows the cylinders not to be immersed entirely in the electrolyte. Using circulating-solution co-deposition (CSD) technique in the novel plating apparatus, Ni-SiC composite coatings can be deposited on the inner surfaces of cylinders, while the outer remains intact. It is of great significance for the engine cylinders whose outer surfaces require high precision to meet the need of specific functions and cannot be corroded by the electrolyte during electrodeposition. The morphology, structure, hardness, corrosion and wear resistance of the Ni-SiC coating in comparison with that of Ni coating have been analyzed. Characterization experiments reveal that the volume fraction of the deposition rate is about 83 μm/30 min. In comparison with pure Ni coating, Ni-SiC composite coating exhibits better anti-corrosion performance, higher hardness as well as greater wear resistance. The predominant wear mechanism for Ni-SiC is abrasive wear and oxidational wear. These results prove that the CSD technique is an efficient technology to prepare Ni-SiC composite coatings with excellent corrosion and wear resistance at a high deposition rate. The composite plating apparatus proposed for large-scale industrialization plan is worth to be highly recommended.

Transient free convective flow in an annular porous medium: A semi-analytical approach

The transient fully developed free-convective flow of viscous incompressible fluid between two concentric vertical cylinders filled with porous material and saturated with the same fluid have been analysed due to isothermal or isoflux heating of the outer surface of inner cylinder. The governing partial differential equations of motion and energy are transformed into ordinary differential equations using Laplace transform technique. The ordinary differential equations are then solved analytically in Laplace domain. The Riemann-sum approximation method is used to invert the Laplace domain into time domain. The solution obtained is validated by comparison with closed form solution obtained for steady states which has been obtained separately. An excellent agreement was found for transient and steady state solution at large value of time. The governing partial differential equations are also solved by implicit finite difference method to verify the present proposed method. The variation of temperature, velocity, skin-frictions and mass flow rate with dimensionless parameter controlling the present physical situation are illustrated graphically and discussed. It is observed that velocity and temperature increases with time and finally attains its steady state status. Furthermore, both velocity as well as temperature of the fluid is higher in case of isothermal heating of the outer surface of the inner cylinder compared with the isoflux heating case when the gap between the cylinder is less or equal to the radius of inner cylinder while reversed trend is observed when the gap between the cylinders is greater than the radius of inner cylinder for all considered values of time.

Steady fully developed mixed convection flow in a vertical micro-concentric-annulus with heat generating/absorbing fluid: An exact solution

Abstract This study investigates the influence of heat generating/absorbing fluid on fully developed mixed convection flow in a vertical micro-concentric-annulus (MCA) taking into account the velocity slip and temperature jump at the outer surface of inner cylinder and inner surface of outer cylinder. Exact solution of momentum and energy equations is derived separately in terms of Bessel’s function of first and second kind for heat generating fluid and modified Bessel’s function of first and second kind for heat absorbing fluid. The solutions obtained are graphically represented and the effects of governing parameters on flow formation and heat transfer aspects are investigated in detail. During the course of numerical computations, it is found that increase in heat generation parameter enhanced the temperature and velocity of the fluid but reduced the rate of heat transfer at the outer surface of the inner cylinder while the reverse trend is observed for heat absorbing fluid.

Magnetohydrodynamic mixed convection flow in vertical concentric annuli with time periodic boundary condition: Steady periodic regime

This work reports an analytical solution for fully developed mixed convection flow of viscous, incompressible, electrically conducting fluid in vertical concentric annuli under the influence of a transverse magnetic field, where the outer surface of inner cylinder is heated sinusoidally and the inner surface of outer cylinder is kept at a constant temperature. The analysis is carried out for fully developed parallel flow and steady-periodic regime. The governing dimensionless momentum and energy equations are separated into steady and periodic parts and solved analytically. Closed form solutions are expressed in terms of modified Bessel function of first and second kind. The influence of each governing parameters such as magnetic field parameter, Prandtl number and the dimensionless frequency of heating on flow formation and thermal behaviour are discussed with the aid of graphs. During the course of investigation, it is found that the oscillation amplitude of the friction factor is maximized at a resonance frequency near the surface of the concentric annuli where there is periodic heating. Furthermore, increasing transverse magnetic field decreases the oscillation amplitude of the friction factor.

Effect of radial magnetic field on natural convection flow in alternate conducting vertical concentric annuli with ramped temperature

In this article, a numerical analysis has been performed to study the effect of radial magnetic field on natural convection of a viscous incompressible and electrically conducting fluid within the concentric vertical annuli containing a ramped type temperature profile at the surface of inner cylinder taking into account the induced magnetic field. Two cases are considered which are case 1, when inner cylinder is perfectly conducting and outer cylinder is non-conducting and case 2, has opposite configuration. The governing partial differential equations have been solved by using Matlab software. The influence of Hartmann number and magnetic Prandtl number on different profiles has been presented graphically. It is found that the effect of Hartmann number and magnetic Prandtl number is to decrease the velocity profile in both the cases. This study suggest that the heat transfer can be controlled by using ramped temperature and conductivity of the cylinder.

Numerical Simulation of Cylindrical Hollow Steel Specimen in Quenching

using finite element method to study the stress variation of cylindrical specimen during the cooling process of quenching, through the establishment of the computer models of mechanical property and thermal property, and using computer to perform the numerical simulation of temperature environment and structure in the process of quenching, simplify the operation process on one hand, and facilitate the analyses of complicated nonlinear problems on the other hand. The outcome according to the stress variation of the outside surface of cylinder indicates that during the process of quenching, the cooling speed of the inner surface of cylinder is much slower than that of the outer surface, leading to the reverse between the center stress and the outer surface stress of hollow cylinder, which finally turns into internal stress distribution of structural stress type.

The helix transition of semirigid polymer chains confined in cylinders

In this paper we use an off-lattice bead-spring model to study the behaviors of polymer chain confined in an infinite cylinder by Monte Carlo simulations. Our simulation results show that when the bending energy b increases in the presence of the adsorption energy of the inner-surface of cylinder, the polymer chain is first randomly attracted on the inner surface of cylinder, and then gradually takes on helix structure, and finally is stretched into the rod-like structure. In order to understand the process of structure transition of polymer chain, we calculate the average of number of helical turns per chain Nt, the average percentage Ph of beads of helical structure per chain and the energy fluctuations with different values of bending energy b. The confined semirigid chain can form helical structure with the appropriate bending energy and the proper radius of cylinder. This study can help us understand the conformational behaviors of biopolymers in confined space.