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Based on the mathematical model of quarter car body model being put forward, the indoor platform experiment of quarter car body with hydro-pneumatic suspension system was done. During test, the parameters of dynamic wheel load along with the change of vibration amplitude and frequency were investigated. The results show that: the cycle of acceleration of sprung mass has half cycle lag than unsprung mass, and the main parameters of dynamic wheel load has increased significantly along with the increase of vibration amplitude and frequency. At the same time, through analysis the acceleration time responses of sprung and unsprung mass, it can be shown that hydro-pneumatic suspension has good anti-vibration performance.

Using SGA170 mine car as prototype, this paper establishes simulation model of single trailing arm suspension vehicle steering to trapezoidal mechanism using the ADAMS software, and validates the correctness of the proposed model. It can not only effectively shorten the development cycle, reduce development costs and improve the design precision of products, but also lay a solid foundation for other the simulation software.

The search for optimal conditions for the method of synthesis of copper (II) salts to create a unified one-step method for obtaining salts from natural raw materials was the purpose of this work. During the process of salt production, it is desirable that the product accumulates in the solid phase and is easily separated by phase separation methods. The study of the direct interaction of copper (II) oxide with acids in organic liquid media using a bead mill as a reactor and grinding agent of different nature showed that besides the usual places of localization of product that take place in practice, we can meet unusual places of localization of product, such as the surface of a foreign solid phase in the reactor zone, for example, the surface of the grinding agent, reactor elements, etc. It was found that in some cases, localization on a solid surface could be a favorable localization option in terms of the speed of the process. But it happens not always, because it requires specific methods of separation of film from surface, which can be very expensive. Often, the localization of the product on the solid surfaces is an extremely unfavorable localization option. It was found that different variants of product localization of interaction CuO with acids which were implemented in different proportions, prevented the creation of a unified method for producing salts in such systems

Hydration of cement systems modified by nano additives requires the understanding of its mechanisms. The present research is focused on the investigation of hydration processes in cement pastes modified by multi-walled carbon nanotubes (MWCNTs) suspension. The ultrasonication method was used for homogenization of MWCNTs in the volume of an aqueous suspension. The hydration of cement pastes was assessed by the calorimetry test. The prolongation of cement hydration in case of modification by MWCNT suspension was observed. The microstructure observation by scanning electron microscopy (SEM) was performed for identification of MWCNT's dispergation in hardened cement pastes and for the observation of cement hydration products. The compressive and flexural strength were tested to evaluate the effect of MWCNT on mechanical properties of hardened cement paste.

The effect of a magnetic source of variable strength has been studied on ferro-nanofluid incorporating nanoparticles of Cobalt ferrite (CoFe2O4) with water as a base fluid. Group method has been used to remodel the governing system to a system of ordinary differential equations. The recent study was motivated by inspecting the effect of four parameters including nanoparticles volume fraction, , Prandtl number, , magnetic field strength of the source,, and temperature difference ratio with respect to ambient temperature, . The results showed that the nanofluid velocity and shear stress increased as long as and increase. On the other hand, both are inversely related to the increment in Pr and Temperature distribution inside the boundary layer was noticed to increase due to the increment in Pr values and decrease due to the increment ratios. Contrarily, the heat flux throughout the boundary layer decreased and increased due to increasing respectively. Key words: Ferro-hydrodynamic; Nanofluids; Group Method

The article discusses the problem of increasing the strength of concrete through the use of a suspension based on nanomodified additives with boehmite, graphene and carbon nanotubes. The lack of high performance and efficient dispersion methods limits the possibilities for nanomodification of building materials. Therefore, the research topic associated with assessing the possibility of developing means and methods for dispersing hydrocomposites containing nanoparticles is relevant. The suspensions were treated with ultra-jet treatment. Nano-containing suspensions were studied using a Microtrac Bluewave laser particle size analyzer. The analysis results were the average particle sizes in terms of quantitative and volumetric distributions, as well as the minimum recorded particle size in the samples. The results of compressive strength tests of a batch of concrete samples are presented. It is shown that the use of nanomodified additives leads to an increase in concrete strength.

Water suspension with heat transport into unsaturated-saturated porous media is analyzed. The numerical modeling includes the infiltration of silt. Moreover, the heat energy of suspension is exchanged with the heat energy of the matrix. The deposited silt influence the porosity and hydraulic permeability. The flow model is based on Richard's type equation and empirical van Genuchten - Mualem model describing capillarity driving force and saturation-pressure relation governing the flow in unsaturated part of porous media. The developed numerical method is usable for solving inverse problems determining some model parameters. The numerical method is based on flexible time discretization and a finite volume method in space variables. The nonlinearity in the flow part of the model is solved by iterative linearization based on the idea in Celia et all. The correctness of the numerical approximation is justified also by a different numerical approximation based on space discretization leading to the reduction of the whole system to the solution of ordinary differential equations. But this method requires significantly more computation time. This is not suitable for solving inverse problems. The used method is justified in numerical experiments solving the direct problem.

In the process of ceramic stereolithography, the polymerization process of acrylate is exothermic, resulting in changes to temperature of the slurry, which may affect the quality of green parts. In this work, the heat source input in simulation is based on the in-situ measurement of conversion rate and calculated polymerization exotherm. The simulation results showed that the different structures underwent a 1~3°C maximum temperature rise. A thermal infrared detector was used to capture the in-situ temperature changes in entire exposure surface for several structures during the photopolymerization process. The experimental data validated the simulation results and showed that the temperature change and distribution area in the process were related to the exposure structure. The discontinuous structure and the increase of structural boundary length could accelerate the thermal diffusion, thus reducing the heat concentration in the center. Polymerization rate rose marginally with the incident light intensity until at the intensity of 20 milliwatts. Besides, intensity had little effect on the temperature gradient from the center to the boundary of the exposure area. It is inferred that the additional temperature rise after the peak temperature is an indicator of the occurring of secondary photopolymerization during multilayer exposure. And for the same input energy, reducing the exposure intensity and increasing the exposure time to some extent may help improve the degree of secondary photopolymerization. This work provided valuable guidance for the study of the photopolymerization process and structural design of ceramic stereolithography.

This paper reports the preliminary study on the synthesis of Ni doped CZTS (Cu2ZnSnS4:Ni) particle 5 at.% of Cu by solution method and dispersion of the obtained particles by beads mill method at various dispersing agents (SDS, CTAB, and Tween80). The phase transformation of the obtained particles was analyzed from the XRD spectra and XRF elemental analysis. The phase transformation and amount of Ni-doped to particles was predicted employing commercially available analytical software tool Match! Version 2.x. Moreover, the dispersion characteristics were investigated includes size, size distribution, and zeta potential of bare particles in comparison to various dispersing agents. This characteristic related to the future application of CZTS as an absorber in a thin-film based PV. The XRD analysis showed that the obtained particle contained crystal structure of copper sulfate pentahydrate (75.9 %), Ni(HN2S2)2 (12.5 %), and Cu2ZnSnS4 (11.6%). The XRF elemental analysis showed that amount of Ni-doped was 6.8 at.%; it was higher than the initial design amount of Ni doping. The dispersion of suspended particles was the majority (90%) with an average size of 3.06 µm and only 10 % with size 255 nm. Beads-milling of particles without dispersing agents did not disintegrate agglomerated particles. It is highlighted dispersion only using magnetic stirred with SDS dispersing agent provides the best suspension with a majority (60%) in 166 nm and only 30 % with average size 3.06 µm with relatively high zeta potential (-17 mV). It was concluded that the presence of a multi-phase crystal needs to be resolved either by proper calcination at a higher temperature than 400°C or further heating at a higher temperature during film preparation. High-energy centrifugation of zirconia beads mill caused desorption of adsorbed steric stabilization of dispersing agent under investigation. Further investigation on the coating process to facilitated laboratory fabrication of thin-film absorber with SDS as a dispersing agent is necessary to carry out concerning the properties of the thin-film.

Mucuna pruriens is a tropical leguminous plant containing L-dopa which is the main active ingredient for Parkinson’s disease therapy. The objective of this study was to investigate the physical, chemical, and microbiological stability of M. pruriens seed extract effervescent powders and suspension. The effervescent powders and suspension were prepared using freeze dried M. pruriens seed extract and were stored at 4 °C, 30 °C, and 45 °C. Physical stability was evaluated by observing appearance and determining rheological behavior. Chemical stability was evaluated by HPLC assay of L-dopa content in the formulation. Bacterial, fungal and mold contaminations were assessed by 3MTM PetrifilmTM count plates. Both formulations showed good physical stability. The degradations of L-dopa in effervescent powders and suspension were fitted to pseudo-zero order and second order kinetic models, respectively. M. pruriens seed extract effervescent powders was found to have the longest half-life, about 112 days, when it was stored at 4 °C. The results suggested that M. pruriens seed extract should be formulated in effervescent powders and stored at 4°C to prevent physical and chemical degradation.

In order to consider the fluctuating wind load induced fatigue problem of long span suspension bridge, fatigue reliability formula is modified by assuming the fatigue life is accord with the weibull distribution. Based on the accurate bridge buffeting analysis of time history, the stress time history of components of a suspension bridge in east sea China is simulated, and then the fatigue damages and reliabilities are calculated. The results indicate that the main cables and hangers have enough fatigue reliability under the fluctuating wind load, the fatigue failure will not occur; the stiffening girder has larger fatigue damage, under 40 / (m.s-1) mean wind speed action, the girder of mid-support section’s average fatigue life is only 3.103 years, so the girder’s damage under strong wind action should be taken seriously.

Centrifuging is one of the most complicated technological processes, and centrifuges are the ones of the most complex technological machines. Not all the questions of the theory of centrifuges have been sufficiently developed, in particular, there is no reliable description of hydrodynamic flows in the process of centrifugation, resulting in the impossibility of an accurate prediction of the separation of heterogeneous systems. Circulation and stagnant (“dead”) zones often appear in centrifuge casings, which lead to uneven residence time of the fluid flow and reduced productivity of the centrate. To improve the construction of these machines, as well as to substantiate the technological mode of their operation, experimental studies were conducted, aimed at identifying the dependence between a proportion of the stagnant zones and the rotor speed. Determination of proportion ofthe stagnation zones was carried out by processing and analyzing the response curves obtained at the centrifuge output, after creating a pulsed input disturbance. Studies have shown that an increase in the rotor speed from 350 to 750 rpm leads to a decrease in proportion of the stagnation the stagnation zones in the centrifuge from 12% to 4.5%, thereby contributing to the intensification of the centrifugation process.

The suspension stability of the titanium dioxide of anatase modification, obtained by ultrasonic dispersion (USD) at the ultrasound frequency of 35 kHz in the aqueous medium of the stabilizer for self-purifying fine concrete as a finishing material for building envelope, is studied. The extreme dependence of the zeta potential on the ultrasonic dispersion parameters of titanium dioxide in the aqueous medium of the surfactant on the basis of sodium salts of naphthalene sulfonic acid and formaldehyde condensation products is established. Various variants of the sequence of the surfactant introduction into the titanium dioxide suspension are analysed. The ratio between TiO2 and the stabilizer, at which the zeta potential exceeds the threshold value of 30 mV and the suspension stability is maintained during 15 days, is determined. The optimal sequence of the suspension components introduction and the ultrasonic dispersion time are established. The influence mechanism of intermittent surfactant introduction on stabilization of the suspension of titanium dioxide of anatase modification is offered. The dependences of the fine concrete strength on zeta potential of the studied suspensions are obtained.

It is well known that nanoparticles affect the interaction between lubricants and surfaces with various chemical compositions and different chemical and physical properties. In recent years, nanoparticles have started to play more important roles as lubricant additives for their potential in wear, friction and emission reduction and improving lubrication and fuel economy. Although nanolubricants are frequently used for friction tests, little is known about stability and degree of dispersion of these nanoparticles in viscous liquids. Most of them are unstable, agglomerate or aggregate which sediment over time. Boric acid (H3BO3) has always been a very important material due to its broad range of applications such as in medicine, cosmetics, automotive industry, metallurgy and also for miscellaneous purposes in other areas. Literature survey showed that friction between automobile engine parts could be greatly reduced using microscopic particles of boric acid.This study involves the new invention of successful suspension of nano boric acid (BA) additive added into 5W-40 fully synthetic commercial lubricating oil. This invention is confidential and realized by Murat ÖZAYMAN from Tribor ARGE Co. in Teknopark of YILDIZ Technical University in Istanbul-TURKEY. The particle size of BA is determined with (Transmission Electron Microscopy) (TEM). Backscattering and transmittance profiles proved that nano boric acid (BA) particles were in suspension in commercial engine oil. Suspended BA in engine oil is applied between piston ring and cylinder liner system in order to investigate their effect on friction and wear under boundary lubricated conditions. Simulation and measurement of friction and wear were conducted using a reciprocating tribometer. Surface analysis were performed using 3D digital optical microscope, Field Emission Scanning Electron Microscope (FESEM)/X-Ray, X-ray photoelectron spectroscopy (XPS) and Atomic Force Microscopy (AFM). Boron (B) from BA is well detected, mixed with other elements of additives and protected the surface under boundary lubrication conditions. The results indicate that BA can considerably improve the tribological performance of a piston ring and cylinder liner system under lubricated conditions. It has found that the friction coefficient is reduced with nano boric acid (BA) suspended engine oil and protected the surface mostly on cylinder liner mixing with other additives.

This thesis exploits chassis dynamic performance analysis platform of the passenger carmodule on the basis of based on the VC#.Net software. Its purpose is to significantly shorten thedevelopment cycle of other models located on the same platform in the process of change. It mainlyadopts the interactive form of menu and dialogue to build the platform. Through the way by usinginternal call Adams/Car module to build a similar Car model file and altering some design variables,the suspension and chassis models of required models can be built quickly. In accordance with thepre-designed suspension and vehicle stability analysis project as the model, it achieves rapidsimulation analysis and access to the analysis results in time. The accuracy of the platform wasproved by the K&C test of the developed model. It provides great reference significance for laterproduct development.

The paper features the results of a numerical study regarding the influence that the damping reduction in the primary suspension of the rail vehicle, due to the defect in a damper, has on the ride comfort. The study is based on model of rigid-flexible coupled vehicle, with seven degrees of freedom, where the carbody is modelled as an Euler-Bernoulli type equivalent beam. The results of the numerical simulations show the power spectral density of carbody vertical accceleration and the ride index comfort calculated in three carbody reference points - at the centre and against the bogies, for various cases of reduction in the damping constant of the primay suspension in the axle, compared to the reference value. As a function of velocity, due to the geometric filtering effect, the damping reduction has contrary effects upon the level of vibrations in the carbody and upon the ride comfort.

Jointed track is still used to build the secondary lines where the maximum speed does not exceed 100-120 km/h. Jointed track construction is based by the fact that the rails are joined end-to-end via the rail joints in order to assure the continuity of the rolling surface of the rails. The rails are jointed using two metal joint bars (fishplates) bolted to the ends of adjoining rails. The rail joints are featured with small gaps to allow the thermic expansion of the rails when the environmental temperature is higher than that during the fitting. In this paper, an analytical model for the rail joint considering the influence of the joint gap is presented and analysed. The model consists of three Euler-Bernoulli beams, two for the rail ends of the rail joint and the third beam for the two joint bars, connected to the rail ends by a Winkler layer. The concept of weakness of the rail joint (rail joint deflection/continuous rail deflection) is introduced and used to analyse the static behaviour of three types of rail joints used at CFR (Romanian Railways). The influence of the joint bars length and bending stiffness, and the influence of the joint gap length upon the rail joint weakness is pointed out.

Mathematical models of a suspension strut such as an aircraft landing gear are utilized by engineers in order to predict its dynamic response under different boundary conditions. The prediction of the dynamic response, for example the external loads, the stress and the strength as well as the maximum compression in the spring-damper component aids engineers in early decision making to ensure its structural reliability under various operational conditions. However, the prediction of the dynamic response is influenced by model uncertainty. As far as the model uncertainty is concerned, the prediction of the dynamic behavior via different mathematical models depends upon various factors such as the model's complexity in terms of the degrees of freedom, material and geometrical assumptions, their boundary conditions and the governing functional relations between the model input and output parameters. The latter can be linear or nonlinear, axiomatic or empiric, time variant or time-invariant. Hence, the uncertainty that arises in the prediction of the dynamic response of the resulting different mathematical models needs to be quantified with suitable validation metrics, especially when the system is under structural risk and failure assessment. In this contribution, the authors utilize the Bayesian interval hypothesis-based method to quantify the uncertainty in the mathematical models of the suspension strut.

Three-dimensional slurry printing is a promising tool for making ceramic object but it limits in high dense ceramic powder because of poor suspension capacity. This study uses zirconia powder with an average diameter of 2 μm because its density is 5.67 g/cm3. A treatment protocol is proposed to improve the suspension capacity of zirconia powder including the ball milling, surface modification and resin blending. Experimental results show that adding 1% of isostearyl titanate, a coupling agent, for surface modification can enhance the lipophilicity of zirconia powder. Mixing surface modification powder in resin with a weight ratio of 7:3 and carrying on ball milling with 100 RPM for 6 hours can obtain the diameter of powder less than 400 nm. As a result, the zirconia slurry can obtain good suspension capacity which is over 48 hours.

The article describes results of the determination of the interaction energy between particles of a hydrating binder and filler, a solution and base. It was found that in the case of particles having a diameter of 17 μm, a mineral suspension should be practically stable, since the energy barrier is much higher than the thermal motion energy of the particles and is 166 kT (100% gypsum), 125 kT (100% CaCO3), 63 kT (gypsum-filler 90:10), and 41kT (gypsum-filler 80:20). A further increase in the amount of CaCO3 particles leads to a significant reduction in the barrier, which at the gypsum-to-filler ratio of 70:30 is 6 kT, and at the ratio of 50:50 completely disappears. In the interaction of the smallest particles (5 μm), the energy barrier values are: 44 kT (100% gypsum), 28 kT (100% CaCO3), 18 kT (gypsum-filler 90:10), 7 kT (80:20) and 2 kT (70:30). With the component ratio of 50:50, the energy barrier completely disappears, and the particles become denser in the first potential well.

Calcium aluminate cement (CAC) and hydratable alumina (HA) are the most widely used binders for refractory castables. Nevertheless, CAC as the binder for refractory castable generates some low melting point phases when coupled with SiO2, which deteriorate the high temperature performance of refractory castables. Although hydratable alumina (HA) bonded castables overcome the drawbacks of CAC bonded ones, they demand a longer mixing time and higher water contents due to HA's high specific surface area, as well as increasing the shear stress and viscosity of HA bonded castables. Therefore, in this paper, CAC combined with HA was used as the binder for corundum- spinel castables to obtain better performance. Sodium tripolyphosphate (STPP), dispersing alumina (ADS) and polycarboxylate ether dispersant (FS60) were used as dispersants, and their effects on the rheological behaviors of CAC-HA bonded corundum-spinel castables suspensions had been investigated. According to the viscosity-shear rate and stress-shear rate curves of suspensions with different dispersants, it was suggested that STPP, ADS, FS60 were all helpful for rheological performance of suspensions. Suspensions achieved much better rheological behavior with 0.3 wt.% of STPP, 1.0wt.% of ADS and 0.1wt.% of FS60, respectively. Suspensions with ADS and FS60 presented to be pseudo plastic fluid, which was helpful for the installation process of CAC-HA bonded corundum-spinel castables. And FS60 could simultaneously impart electrostatic and steric stabilization to the given suspension. Considering the actual rheological performance of CAC-HA bonded corundum-spinel castables, FS60 was much better than ADS.

The present study deals with steady incompressible magneto hydrodynamic hyperbolic tangent fluid flow induced by a convectively heated stretching surface with the suspension of dust particles, Darcy-Forchheimer, thermal radiation, viscous dissipation and Ohmic heating. Similarity transformations were used to convert partial differential equations (PDEs) to a system of nonlinear ordinary differential equations (NODEs) which are solved numerically by Runge-Kutta Fehlberg method. The effect of pertinent parameters on velocity and temperature profiles of both fluid and dust phase within the boundary layer has been studied by considering various values of controlling parameters. Additionally, the skin friction coefficient and reduced heat transfer coefficient have been examined for various values of the governing parameters. It is found that Hartmann number and Forchheimer parameter reduce friction factor and heat transfer rates.

In this paper we consider a numerical investigation on sparkplug ignition of nanosized coal-dust suspension in the air. The aim of the research is to determine the effect of radiation transport on minimal sparkplug ignition energy of a coal-dust suspension. The paper provides the data on the sparkplug ignition energy dependence on the suspension emissivity factor and coal-dust content.

The paper studies the behavior of a quarter-car suspension model under periodic road excitation: sinusoidal and bump (trapezoidal shape) for a constant vehicle speed. A theoretical and a finite element model were developed. The theoretical model has two degrees of freedom and a modal and sinusoidal excitation was performed to compare with finite model analysis. The finite element analysis consists of three parts: preload, modal analysis and deterministic external excitation. The study consists of the analysis of forces, displacements and accelerations that are transmitted to the vehicle regarding their variation in time and frequency.

The subject under study is relevant as the enterprises in different industries are really interested in disperse systems in the form of suspensions. Suspensions are being widely used in many fields. At the same time the problems of improving their quality and increasing the productivity and energy efficiency of machines still exist. In this context, this study aims at getting finely divided suspensions of metals through the erosion of metal plates in the cavitation flow reactor. The construction of the reactor provides for a technically and technologically simple high-capacity process. The leading method of the research is a laboratory experiment and a qualitative and quantitative assessment of the erosion of the metal surface in the region of maximum developed cavitation. The article presents the results of the research into the nature the metal surface damage under cavitation. The sampling materials are copper and fine silver. The experiment shows quite a strong growth of numerous erosions and states that in the beginning in the region of maximum cavitation the net of cavities appears. Then, the cavities fuse and grow in size. Around single caves the areas of plastic deformation with typical metal flows are detected. The minimal sizes of particles, torn away from the surface, are 2-3 mcm. The study is of high practical value for researchers and specialists in nanotechnologies, solid dispersion, sedimentary analysis, flow detection, biomedicine, production of fuel, lubricants, emulsifiers, catalysts, and semiconductors.

A comprehensive numerical study is conducted to investigate effect of nonlinear thermal radiation on MHD boundary layer flow and melting heat transfer of micro polar fluid over a stretching surface with fluid particles suspension. Using suitable transformations, the governing equations of the problem are transformed in to a set of coupled nonlinear ordinary differential equations and then they are solved numerically using the Runge–Kutta–Fehlberg-45 method with the help of shooting technique. Authentication of the current method is proved by having compared with established results with limiting solution. The impact of the various stimulating parameters on the flow and heat transfer is analyzed and deliberated through plotted graphs in detail. We found that the velocity, angular velocity and temperature fields increase with an increase in the melting process of the stretching sheet. Also it is visualize that the shear stress factor is lower for micro polar fluids as compared to Newtonian fluids, which may be beneficial in flow and heat control of polymeric processing.

This article presents a numerical investigation on the convective heat transfer behaviour of time-dependent three-dimensional boundary layer flow of nano-suspension over a radially stretchable surface. The modeled set of governing nonlinear coupled ODEs is solved using the finite difference scheme followed by the shooting technique. For understanding the effects of various physical parameters such as geothermal viscosity, stretching parameter and viscous dissipation on the flow and temperature fields, magnetite-hydrocarbon nanofluid 90G is taken. The heat transfer rate and skin frictions due to the above physical parameters are also computed. The derived results show that among these parameters, Eckert number has a dominating role in the heat transfer. After a critical value of the Eckert number, the rotating surface is no longer getting cooled, rather, it takes up heat despite the fact that the surface temperature is more than the ambient temperature.

Suspension-bridge cables are constructed from strands of galvanized steel wire. They are failure-critical structural members, so a fundamental understanding of their mechanics is imminently important in quantifying suspension bridge safety. The load-carrying capabilities of such strands after local wire failures have been the subject of many theoretical studies utilizing analytical equations and finite-element analysis. Little experimental data, however, exists to validate these models.Over the past five years we have developed a methodology for measuring stress/strain transfer within parallel wire strands of suspension bridge cables using neutron diffraction [1,2]. In this paper we describe the design and verification of parallel cable strands used in our studies. We describe the neutron diffraction strain measurements performed on standard 7-wire and expanded 19-wire models in various configurations at both the Los Alamos National Laboratory Spectrometer for Materials Research at Temperature and Stress (LANL SMARTS) and at the Oak Ridge National Laboratory VULCAN Engineering Materials Diffractometer (ORNL VULCAN). Particular attention is placed on the challenges of aligning and measuring multibody systems with high strain gradients at body-to-body contact points.

In industrial applications, it is very common to use multiple hydrocyclones in parallel to improve the separation. This equipment employs the centrifugal field to promote solid-liquid or liquid-liquid separation. In cases where there is interest in recovering the liquid phase by removing the maximum amount of dispersed phase (waste), such as in oil well drilling units and in water treatment systems, the employment of a hydrocyclone able to promote both the recovering liquid and the concentration of suspension is viable. This paper presents a comparison between two hydrocyclones considered concentrators, called H13 and HCOT3. The results obtained showed that both separators have a satisfactory capacity to concentrate aqueous suspensions, with the underflow-to-throughput ratio equivalent. The Euler number of HCOT3 hydrocyclone was 19% lower than that obtained for the H13 hydrocyclone. Moreover, the results showed that the HCOT3 has a total efficiency of separation 34% greater compared to H13.

Hydrocyclones are equipment typically used in solid-liquid separation. Such equipment can be used with the purpose of classifying particles or concentrating suspensions. In this context, a new filtering hydrocyclone was conceived through Surface Response and Differential Evolution Algorithm techniques in order to optimize the Euler’s number. Based on this optimized geometry, the aim of the present paper was to verify the influence of the underflow diameter on the overall separation process at 147 kPa on the same optimized hydrocyclone geometry, but without the filtration effect, by performing laboratory experiments and CFD simulations using the commercial software Fluent®. The results showed that the use of the smallest underflow diameter increased up to 44% (v/v) the concentration of the underflow stream, compared to the suspension initially fed, with an Euler’s number of 862. Despite a small decrease (14%) in the total efficiency and an increase from 12.01 to 16.05 of the reduced cut size diameter, compared to the underflow diameter originally used in the optimization procedure, the benefits of recovering liquid by reducing the underflow diameter outweigh these disadvantages.

Due to the restriction of passive layers containing Cr6+ [1], which were characterized by excellent corrosion protection due to their self-healing effect for scratches on metal surfaces, current corrosion protection systems consist of chromium (III) -containing thick layer passivation. Due to their lower hardness, current corrosion protection systems are susceptible to mechanical stress. This is particularly critical at barrel plating of screws, rivets etc. where the manufacturing process leads to damages of the corrosion protection layer and consequently to reduced corrosion resistance.To counter this problem, we point out one approach to install hard particles into the passivation layer. The entrapment of the hard particles into the passivation is detected by Glow Discharge Optical Emission Spectrometry. Comparative investigations in the corrosion chamber prove the improvement of the corrosion protection of steel parts with passivation layers containing hard particles.

In this paper, graphene nanosuspension was spray deposited using electrohydrodynamic atomization (EHDA) technique, and the polydimethylsiloxane (PDMS) was used as the substrate during the EHDA process. The effect of the PDMS substrate before and after oxygen plasma treatment on the characteristics of EHDA was examined. A cone-jet mode of the EHDA of graphene nanosuspension was obtained using the oxygen plasma treated PDMS substrate. In addition graphene films were deposited on the oxygen plasma treated PDMS at different working distances. The lowest sheet resistance of the graphene films is 127Ω·sq-1. Furthermore, graphene lines at the range of 30μm-170μm were fabricated using the template assisted EHDA deposition method.

In order to improve the strong nonlinearity and uncertainty of the suspension system, the suspension system was transformed into two different linear subsystems by the Taylor’s formula and the proportional-integral-differential controller based on genetic algorithm was designed in this article. Optimizing the code, the population size, the crossover probability, the mutation probability and the maximum number of iteration, we obtained respectively the optimized parameters of the controllers of the electromagnet 1 and the electromagnet 2. The simulation results showed that the optimized suspension system had a good robustness.

Axial suspension plasma spraying (ASPS) is a relatively new, innovative spraying technique which has produced thermal barrier coatings (TBCs) with attractive properties such as high durability and low thermal conductivity. Using a suspension, it is possible to spray with finer powder particles resulting in coatings that have a columnar microstructure and contain a wide range of pore sizes, both nm-and μm-sized pores. To optimize the thermal properties and to maintain them during service of the components, it will be important to design TBCs with optimal porosity. Hence, an important part in the assessment of ASPS coatings is therefore the characterization of the microstructure and how it is build up, and the determination of porosity. Both aspects are addressed by performing measurement on splats and ASPS-coating using electron backscatter diffraction (EBSD) technique and by measuring porosity by Mercury Intrusion Porosimetry (MIP).

In order to break through the limitation of the width of river, depth of water, channel and etc., it is an optimal choice to construct a long-span suspension bridge. In a suspension bridge, the main cable is the major bearing member; and the use of super high strength cable wire can lighten the dead weight and obtain an economical design. 1960 Mpa cable wire is adopted by an under-construction suspension bridge, namely Ni-Zhou Channel Bridge, for the first time in China. In this paper, taking the Ni-Zhou Channel Bridge as a case-study, comparative analyses on dynamic characteristic and seismic response of long-span suspension bridge with 1960 Mpa cable wire are performed. Firstly, dynamic calculating model for Ni-Zhou Channel Bridge is built and its dynamic characteristics are studied; then by using response spectrum and time history analysis method, seismic response of Ni-Zhou Channel Bridge is investigated on the basis of design response spectrum and artificial seismic ground motions; finally, the energy dissipation performances of a seismic protection devices (viscous damper) are also discussed. The results show that long-span suspension bridge with 1960 Mpa cable wire has a longer natural vibration period; the use of viscous damper can effectively reduce the peak value of bending moment in stiffening girder. This paper can provide references for the project’s construction.

In automobile application, suspensions are used for various purposes. To improve the stability and to withstand maximum load we are trying to add additional source which is called suspension. These suspensions are made attached along with the ordinary suspension. This is manufactured using magnetic fluid called ferrofluid. Here the complete preparation of ferrofluid was done and their characteristics were studied. In this, the experimental setup of suspension has been studied and working was analyzed. The fluid was prepared and compared the viscosity with ordinary fork oil. This liquid substance which acts as a source of suspension, which has maximum efficiency when compared to ordinary fluid. These can be varied to different shapes depending on the application and needs.

A half tracked vehicle model was established based on LMS, a co-simulation interface between control algorithm of MATLAB and physical model of LMS was set up. Fuzzy controller with PID regulator was proposed to achieve controlling strategy based on half tracked vehicle model. With suspension stroke and its change rate as input parameters of fuzzy controller, the dynamic adjusting parameters of PID controller are acquired through fuzzy controller, then a semi-active suspension vehicle adaptive control system was formed. The simulation result shows that the adaptive control system can effectively coordinate the contradiction acceleration and dynamic travel in different bands, the ride comfort tracked vehicle is significantly improved.

This paper presents the results of an investigation into obtaining water-coal suspension from brown coals of Kansk-Achinsk basin using the electrohydraulic method. The obtained results are the basis for developing the technology of obtaining water-coal suspension using electrohydraulic crushing.

During the last decades under the enthusiastic and competent guidance of Mr Chiarmetta SSM processes attained in Italy at Stampal Spa (Torino) an unquestionable high level of industrial development with the production of large numbers of high performance automotive parts, like variety of suspension support, engine suspension mounts, steering knuckle, front suspension wheel, arm and rear axle. Among the most highlighted findings SSM processes demonstrated their capability to reduce the existing gap between casting and forging, moreover during such a processes there are the opportunity to better control the defect level.Purpose of this paper is to highlight the research work and the SSM industrial production attained and developed by Mr G.L. Chiarmetta, as well as to give an overview concerning some alternative methods for the production of enhanced performance light alloys components for critical industrial applications and to present an analysis of a new rheocasting process suitable for the manufacturing of high performance industrial components.

The diversity of physical and mechanical properties of aluminum alloys leads to develop a variety of manufacturing processes including the semi-solid casting process. Fatigue failure is considered the most common problem occurred in automotive engineering applications by which the vehicle components, mainly suspension system parts, fail under conditions of dynamic loading. It is well known that the fatigue life of aluminum castings, mainly A357, is very sensitive to casting design as well as to casting defects and microstructure constituents. The fatigue characteristics of automotive lower suspension arm made of semi-solid A357 aluminum castings have been investigated using metallurgical and analytical approaches. The critical stress areas capable of initiating cracks during fatigue tests are detected by using fatigue experimental design for real part materials by the installation of strain gages on the suspension arm to calculate maximum stress; further more, analytical approach is applied using modelling software. Microstructure characteristics of the semisolid A357 under T6 heat treatment conditions are examined using scanning electron microscope. The results show that using the SEED casting technology (Swirled Enthalpy Equilibration Device) has an efficient effect on the mechanical and metallurgical characteristics of real part materials that are also affected by castings design.

Taking the trapezoidal link rear independent suspension which is designed for Crossover as the object of study, the multi-body dynamic analysis software ADAMS/CAR is used to establish the kinematics model and carry out the simulation analysis. And then, study the influence of the suspension system on the vehicle handling stability and make the evaluation under the conditions of wheel travel, applied load and body roll, which provides a basis for optimizing the suspension and improving the handling stability of the trapezoidal link rear independent suspension to the Crossover.

In this present work, the approaches providing establishment of transitional value of Reynolds number when filtering liquids in the magnetized granulated (polyspherical) matrix are considered. It is shown that value of transitional number of Reynolds by flow through the granulated matrix is not crisis for process of a magnetophoresis. It is confirmed on the example of magnetophoresis of ferroparticles in water suspension, thermal power plant condensate, liquid ammonia. It is established that the effective of magnetophoresis could be performed also in case of Reynolds's values much more than determined hydrodynamic Reynolds number. It significantly expands idea of the beginning of crisis of the magnetophoresis regime and allows to receive the limiting filtering speed for any media passed through a zone of a filter magnetophoresis.

In suspension bridge, the main cable is the major bearing member, instead of the 1770MPa cable wire normally adopted in current design, the application of cable wire strengths up to 1960MPa can lighten the dead weight, reduce the size of tower and anchorage, and shorten the construction period, obtain economical design. In this paper, a under-construction suspension bridge with span of 1688m is taken as a case-study, Comparative analyses are performed mainly focusing on basic parameters, carrying efficiency of main cable, static behavior and dynamic properties as different high strength cable are adopted in this suspension bridge. The results show that compared with 1770MPa main cable, using 1960MPa main cable in suspension bridge is benefit for improving the carrying efficiency of main cable, the steel consumption is also saved by 13%, but the vertical stiffness of the structure is reduced partly; the changes of main cable slightly affect the natural vibration frequency of girder, but have greater influences on vibration of main cable.

In this study, a TiO2 ceramic membrane was coated on the porous Al2O3 ceramic support by a dip-coating method using a self-designed apparatus. A flat, low-porous and uniform membrane was obtained based on the optimized ingredient and fluidity of TiO2 suspension. The effects of thickening agent content on the stability of the membrane casting solution and the microstructure of the membrane were investigated.

The work deals with an analytical algorithm for determining the static equilibrium position of the multi-link guiding mechanisms used for the rear axles of the motor vehicles. The method is based on the virtual mechanical work principle, considering the external forces applied to the wheels, as well the reaction forces in the elastic elements of the suspension. The equilibrium position of the guiding mechanism is established relative to the car body, considering the static model of the suspension system, in which the car body is fixed connected to ground (in other words, the car body is the reference part of the system). For determining the reaction forces in the elastic elements of the suspension (springs, bumpers and rebound elements, bushings, anti-roll bar), an original method for the positional analysis of the axle guiding mechanisms was developed and integrated in the mathematical algorithm for establishing the equilibrium position.

When power equipments are suspended under the under-frame of a rail train vehicles, dynamic and vibration characteristics of the car body will be changed. In order to study suspended parameters of the car body dynamic system, the vertical dynamic coupling model of rigid car body and power equipment under different exciting force was established. Results showed: when the exciting force of suspended power equipment is zero, the elastic suspension stiffness and damping can be designed according to the principle of Dynamic Vibration Absorber (DVA); when the exciting force acting on the rigid car body is zero, the vibration isolation problem of equipment is consistent to the base isolation problem, a good vibration isolation effect can be obtained as; when the body and power equipment simultaneously be excited, vibration absorbing and isolation must be simultaneously designed: the DVA is meet on at first, when ,the suspension isolation system appeared two different frequency peaks, but only , a good vibration isolation can be obtained for suspension system.

The paper concerns model based identification of vibratory machine body suspension system on the basis of dynamic responses measured under exploitational conditions. The research was carried out by means of the restoring force, boundary perturbation and direct parameter estimation techniques which, on the contrary to classical nonlinear system identification methods, requires neither excitation measurements nor linear behaviour of the considered system around an operating point. At the first stage of the research, parameters of the machine body suspension system were identified. Results accuracy was verified by determining percentage relative error of mass estimation with respect to the value calculated based on the machine geometrical and material properties. In the next step, the suspension system was modified by introduction of a nonlinear damping system. Obtained results proved that the assumed identification method is convenient for vibratory machine suspension condition monitoring and determining forces transferred on machine foundations.

The problem of optimal control of systems disturbed by sinusoidal signals for infinite control time is considered in the paper. The control laws described in [1] is base of a modified mean-square performance index with an infinite control time. The performance index was formulated in such a way that each sinusoidal component corresponds to a separate weight matrix. This allows energy constraints on the control signals to be differentiated based on frequency. An optimal solution to the optimization problem was found. In the paper the problem of the impact of time on the identification of sinusoidal disturbance on vibration isolation system frequency characteristic. The controller was synthesized for slow-active vehicle suspension [2,3]. The model of suspension, synthesis of the controller and implementation of the system was described. The results of simulations of the designed vehicle active suspension system are presented.