Materials Engineering at IgMin Research | Engineering Group

The paper explores comprehensive Unmanned Aerial Vehicle (UAV) wing optimization, integrating aerodynamic and structural techniques. A detailed comparison between the base and optimized modules while considering specifications such as composite material orientation, spar and rib material, deformation, stress, strain, safety factor, and weight. The methodology utilizes material changes for wing weight reduction while maintaining structural integrity. The optimized module (Case 7) balances weight reduction, safety, and structural performance, not...ably shifting from Al 7075 to Al 2024. Structural optimization focuses on changes in Carbon Fiber/Epoxy orientation, leveraging material changes for weight reduction. Constitutive equations and transformation matrices calculate stiffness matrices for the laminate, resulting in a robust wing. This holistic optimization combines low and high-fidelity techniques, addressing UAV wing structural aspects. Outcomes include weight reduction, deformation minimization, fluttering modal deformation and buckling points, an increased factor of safety, and improved strength-to-weight ratio. The research significantly advances aerospace engineering, particularly in UAV design and optimization.Read more

Reconstruction of pulverized coal boilers BKZ (Barnaul Boiler Plant, steam productivity 160 t/h, pressure 100 kgf/cm2, fuel: natural gas/fuel oil) with steam productivity of 160 t/h, converted to gas combustion, and an increased load capacity to 210 t/h, has been carried out. As part of the boiler modernization, a chemical water treatment system was reconstructed, significantly improving the quality of feedwater: hardness not exceeding 0.3-0.5 µeq/kg; SiO2 not exceeding 18 µg/kg, and electrical conductivity Х=0.6-1.0 µS/cm. T...he previously used phosphate regime for boiler water was replaced with a chelant-based regimen using trilon B. During operation, widespread damage to the screen tubes occurred. Circulation tests were conducted on one of the boilers, and an analysis of internal deposits was performed.It was determined that water circulation in the side screen is stable, and its velocities correspond to calculated values. The main cause of metal ruptures in the screen tube is metal corrosion, as well as local overheating of the wall caused by the formation of a steam layer due to the detachment of internal deposits.Read more

The textile sector has great relevance in the Brazilian socioeconomic context, generating large volumes of effluents of varied composition, with dyes being one of the most worrying contaminants due to their characteristics of high solubility, harmfulness and low degradability. Among them the Reafix Yellow B8G (ARB8G) dye has an azo nature, harmful to organisms in the aquatic environment. According to Brazilian laws, it is recommended to dispose of waste through incineration or landfill, due to its resistance to biodegradation. One of the method...s for treating effluents is the adsorption of contaminants using materials with adsorption capacity, such as residue from the burning of biomass in boilers (ash). The general objective of this work was to evaluate the adsorption kinetics by contact time of the ARB8G dye by boiler ash. The test was based on mixing the adsorbent material with a dye solution at 75 mg.L-1, at constant temperature and stirring at different time intervals. To quantify the amount of adsorbed dye, the UV-Vis spectrometry method was used. The kinetic test indicated an equilibrium time of 30 minutes, with 100% removal under the tested conditions. From this result and considering that boiler residue is an underutilized and low-cost material, it is concluded that this substance has significant potential to be applied as an alternative material for the treatment of effluents containing dyes.Read more

A new design of a fine positioner or high precision driven unit with a large positioning range is proposed for a custom-made in-situ indenter device equipped inside an SEM chamber. The design configuration of the proposed system is size-effective for the confined working area of the SEM chamber. The indentation depths can be precisely varied by controlling the fine positioner driven by a piezoelectric actuator. The main goal is to achieve very deep penetrations toward the bottom layers of tall or large-size scale specimens by single indentation..., without the need for sequential indentations. Thus, the proposed design can eliminate the need for sequential adjustments of the specimen position with respect to the indenter tip as currently being practiced by the researchers. The specimen position adjustment after each indentation heavily depends on the coarse positioner and its accuracy level in a sub-millimeter regime which could result in position errors and unwanted lateral forces in the nanoindentation process. Therefore, the sequential indentations technique could lead to considerable variations in the outcomes of nanoindentation tests done on similar specimens. The proposed design will be realized to deploy in the Continuous Stiffness Measurement (CSM) techniques generally used to evaluate elastic properties as a function of continuous penetration depth with high-frequency loading and unloading cycles.Read more