Papers by Keyword: Suspension

Abstract: Uprights are one of the most critical structural elements in vehicles suspension systems. A standard upright serves as a physical mounting for the wheel hub and brake components as well as links the axle to the control arms. Uprights are relatively bulky by design to withstand the significant loads they observe during vehicle braking, maneuvering, and driving on rough terrain. In automotive design, specifically, race car design, utilizing lightweight components and reducing fuel consumption are imperative. This weight reduction-based paradigm is being adopted by the car industry at large, particularly due to the shift towards automotive electrification. Consequently, this work investigates the potential for using topological optimization to reduce the bulkiness and weight of uprights without compromising their structural integrity and reliability. An upright designed for a racing car is selected in this study. Topological optimization is performed on the upright using the finite element software ANSYS. Results show that a considerably enhanced upright is obtained after 48 topological optimization iterations while maintaining a factor of safety of 2.5. The optimized upright exhibited less stress concentrations and 39% lesser weight than the original upright.

Abstract: The article presents potentiometric (pH-metric) methods that are used to study the acid-base properties of the surface of dispersed materials of different chemical nature. It is shown that the surface of any solid body has a surface hydroxyl-hydrate layer with a set of active adsorption centers (ACA) of different chemical structure and a wide range of acid-base properties. It has been proven that potentiometric (pH-metric) methods of studying dispersed materials in suspensions allow obtaining the most complete information about surface acid-base properties.

Abstract: To dehydrate technical suspensions, diverse in composition, the filter baffle plates made from synthetic fibres (nylon, polyethylene terephthalate (lavsan), tetrafluorethylene (tephlon), ftorlon) are used. High retention capacity of the filter baffle plates on the dispersion phase of the suspension is one of the major requirements. The article represents the assessment of the filter properties the double-layer baffle plates have: cotton, consisted of filter diagonal art. 2074 (substrate) and coarse calico (base), and synthetic nylon, consisted of the fabric art. 56027 (substrate) and the fabric 56159 (base). The kinetics of the filtration process of the different in composition dispersion suspension particles of the red mud has been studied. The formation conditions of the initial filter layer have been described.

Abstract: Textile dyeing often employs reactive dyes. The dye wastewater contains hazardous materials and is toxic to humans and the environment. Photodegradation using a semiconductor photocatalyst is a promising alternative approach for water purification and wastewater treatment. However, the photocatalyst’s low adsorption ability is a problem in the photocatalysis process. To compensate for this shortcoming, photocatalyst content must be combined with an adsorbent. Raw corn cob and titanium dioxide (TiO₂) were used in this photocatalysis. Due to a synergistic impact, raw corn cob’s ability to adsorb and titanium dioxide’s ability to photodegrade organic pollutants from water bodies is expected to boost the removal performance. The degradation of Reactive Blue 4 (RB4) as a targeted dye was carried out in this research using a suspended mixture of commercial anatase TiO₂ and raw corn cob under UV light. The effect of initial pH solution, initial dye concentration and contact time, TiO₂-corn cob dosages, and the influence of other pollutants were investigated as factors influencing photodegradation-adsorption of RB4. The high removal rate of RB4 was obtained at a low pH of 2 and RB4 concentration of 40 ppm. The increased dose of TiO₂-corn cob improved the RB4 dye removal performance. In conclusion, combining photodegradation and adsorption systems as a hybrid treatment method resulted in a synergistic increase in the efficiency of RB4 removal.

Abstract: 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

Abstract: 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.

Abstract: 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

Abstract: 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.

Abstract: Most advanced driver assistance systems (ADAS) are intended to improve ride comfort for vehicle suspension systems. A new road estimation method is proposed as a means of observing the road profile level. To achieve this, two complexity levels (quarter car and half car models) are presented and developed in Matlab to analyze the vertical vibration of a vehicle. The unknown input observers are then designed for observing unknown states and road profile level. The necessary measurements are the accelerations of the centers of the wheels. The results of simulations conducted with random road excitation show successfully simulated experimentations of the method using a realistic simulator as well as its robustness.

Abstract: 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.