Papers by Keyword: Rotation Speed

Abstract: Owing to the high mixing capacity, the stirred tank reactor is the key class of reactors in the chemical process industry and pharmaceutical industry. The mass transport nature of a batch stirred tank reactor with a fixed copper wall with a cylinder form was studied using copper dissolution in acidified dichromate which is controlled by diffusion. Variables analyzed included the speed of rotation of the impeller, the shape of the impeller and the physical specifications of the solution and the existence of baffles. The data were correlated for the conditions 3667.323 < Re < 34993.18 and 960 < Sc < 1364, for radial flow by the equation: Sh =0.3453 *Sc^1/3*Re^0.66 but for axial flow by the equation: Sh =0.5866 *Sc^1/3*Re^0.59. Through speed of rotation of the impeller increases,it allows the rate of mass transfer from the fixed bed to the solution to rise. The radial-flow turbine is more effective than the axial-flow turbine in increasing the rate of mass transfer. The usage of baffles plays a significant role in rising the rate of mass transfer. Using baffles; the correlation will be Sh =0.0769 *Sc^1/3*Re^0.84 for radial flow and Sh =0.1157 *Sc^1/3*Re^0.78 for axial flow. The purpose of this research is to estimate the rate of mass transport that can be required in corrosive reactions, and also to maximize the mass transfer rate that can be achieved in other processes, such as electroplating in presence of baffles.

Abstract: In this paper the task of the study of the deformation during helical piercing of the metal was set and solved with the use of the DEFORM-3D software. Methodology, that allows to calculate the length of helix lead along the deformation zone, as well as determine for each lead absolute and relative reduction, the width of the contact area and the metal strain refinement indicator was developed. Based on the developed methodology application the following variation regularities were established: helix lead length (l_i), quotient reduction (Δr/r₀), ratio of the billet radius to the width of the contact area (r₀/b), as well as the length of the billet contact surface (l₀) with the roll in dependence of the feed angle (β), the roll number of revolutions (N) and the plug nose advancement over the gorge (C_g).

Abstract: Inhibitor is a chemical compound which commonly used to control corrosion in a tank or a pipelines. Organic inhibitor recently developed because of the availability and the ability to act like commercial inhibitor. The performance of mixed inhibitor was studied on St 41 carbon steel immersed in NaCl solution containing CO₂ gas. Research parameter used were pH 4 and 6, rotation speed of 150 and 250 rpm, with mixed inhibitor volume ratio of 1 (imidazoline) : 2 (paracetamol), 1:1, also 2:1. The Weight loss measurement, isotherm adsorption calculation, FTIR, and XRD measurement have also been done. Based on weight loss test, the highest inhibitor efficiency was 61.412 % at pH 6, 150 rpm, with inhibitor volume ratio of 2:1, adsorption isotherm calculation indicate the adsorption mechanism of the mixed inhibitor is physical adsorption. Tafel test result showed the tendency of inhibitor worked anodically. The FTIR spectrum result found functional group of N-H from the inhibitor precipitated on the metal surface after ten days of immersion Based on the EIS result, there was an increase value of polarization resistance value and decrease on CPE (constant phase element) value. While X – ray diffraction (XRD) result from the volume ratio of 1:2 confirm the CO₂ corrosion product FeCO₃ and Fe₂O₃ formed on metal surface. With volume ratio of 2:1 mixed inhibitor, it was confirmed that iron nitride (Fe₂₄N₁₀) compound was formed on steel surface because of the chemisorption reaction between Fe and nitrogen atom from pyridine at the imidazoline inhibitor. The inhibition mechanism was physisorption for entire parameters, based on calculation of Langmuir adsorption theorem.

Abstract: There is an ever increasing demand for use of inductive speed sensors in a broad range of applications. They are used in typical applications such as cam and crank shaft position/speed and wheel and turbo shaft speed measurement. This paper describes the type of inductive sensor found on vehicles and the difficulties of detecting at low speeds. In the laboratory of Mechatronics an experimental device has been done to measure the speed using an inductive speed sensor. The experimental results are satisfactory and show the possibility of the inductive sensors to be used in automotive industry.

Abstract: Ti coatings on alumina (Al₂O₃) balls had been prepared by mechanical coating technique (MCT), and the influence of the rotation speed on the coating formation process were investigated. The crystal structure and microstructure of the Ti coatings were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The formation process of Ti coatings was examined and discussed. The results showed that the rotation speed had great influence on the coating formation process. With increasing the rotation speed, the speed of coating formation had been accelerated and the surface became to be uneven. It was considered that the formation of metal coatings consists of 4 stages: nucleation, formation and coalescence of the discrete islands, formation of the continuous coating, and exfoliation.

Abstract: Hydrogen as the main cause of the gas porosity in aluminium alloys should be removed before casting. The degassing process with intensive melt shearing shows a high efficiency. In the present work, the water simulation was used to study the high shear degassing process and the effect of rotation speed on the size and distribution of inert gas bubbles. The results show that with the increase of rotation speed, the bubble size decreases and the affected region becomes larger. The proper rotation speed of the rotor for the rotor-stator high shear degassing process is 5000-6000 RPM.

Abstract: This paper explores effect of rotation speed and media loading on grinding performance of the horizontal stirred mill using the combined method of experiment and simulation on prototype. It selects rotation speed and filling rate to constitute simulation experimental group and conduct the simulation in the EDEM. By studying the effect of rotation speed and medium filling rate respectively on the movement of the medium, the power and the energy utilization,it draw the conclusion of the effect of the rotation speed and medium filling rate on the grinding performance.

Abstract: The paper uses the control variable method, to analysis the effects of rotational speed and media loading on grinding performance on a 230×338 horizontal stirred mill. By comparing the effects of rotational speed and medium filling rate on grinding particle size distribution, the conclusion is that increasing the rotational speed and medium filling rate can get the particle with small and concentration size.

Abstract: Ink is one of the important material in printing process, its features, to a great extent, decide the printing quality, and ink viscosity is one of the main parameters, the value of the ink viscosity directly affects the quality of printing. In the case of other conditions are determined, the main factor of influencing the ink viscosity is temperature. In this paper, by using the Workbench CFX fluid simulation software, the ink temperature field of two extrusion ink rollers in printing press is analyzed by numerical simulation , the influence of the ink roller speed on ink temperature and the influence of ink roller thermal conductivity on the ink temperature are analyzed,.

Abstract: The lubrication state of three-lobe bearing is simulated by using Reynolds equation. It concluded that the load-carrying capability of three-lobe bearing increases with the eccentric distance between the centers of axis and bearing with a nonlinear way. The largest bearing load-carrying capacity occurs in the eccentric direction of 30 °and making sure the eccentric direction can improve the stability of the system. To improve the rotation speed of the axis is beneficial to promote the load-carrying capacity.