In this research, a detailed finite-element (FE) analysis of the combined influence of the drilled-hole position, the shape of the hole, and the fillet design on the structural and dynamic performance of spur gears is investigated. ANSYS R16.2 was used to create a three-dimensional numerical model that can be used to assess the bending stress distribution and vibration response under realistic loading conditions. A trochoidal fillet and four circular fillet radii (0.5, 1.0, 1.5 and 2.0 mm) were studied to determine their effect on the stress concentration behavior. FE-guided hole-suggestion process was introduced which is an automated process in which low-stress zones to be cut away are identified so as to allow systematic recommendation of optimal locations, orientations and size of holes without any empirical relation. It was found that root stress decreased dramatically as fillet radius was increased, and 2 mm fillet had the minimum bending stress of all circular arrangements. The baseline configuration (Rf = 0.5 mm, without holes) exhibited a maximum bending stress of 69.45 MPa, whereas increasing the fillet radius to 2.0 mm resulted in a stress reduction of approximately 35%. The trochoidal fillet provided less stress gradients and a larger zone of low stress surrounding the tooth root. The holes proposed by FE were further incorporated, which increased structural performance. Hole size out of the chosen geometric parameters was statistically most impactful on bending stress and dynamic response, which ANOVA proved to be accurate (p < 0.001). The holes in the top the most desirable performance were medium-size (≈2.0–2.4 mm) drilled horizontally, which minimized bending stress by about 46%–50% relative to the baseline gear and ensured very low peak dynamic displacement (∼3.4 × 10 −5 m at approximately 73 Hz). Structural integrity is well enhanced by optimizing fillet radius and drilled holes sizes, directions, and locations regarding the strength and dynamic stability. The proposed methodology offers a reliable and scientifically grounded framework for gear modification with strong potential for integration into advanced gear design and light weighting applications.
A polycrystalline CdTefilms have been prepared by thermal evaporation technique on glass substrate at room temperature. The films thickness was about700±50 nm. Some of these films were annealed at 573 K for different duration times (60, 120 and 180 minutes), and other CdTe films followed by a layer of CdCl2 which has been deposited on them, and then the prepared CdTe films with CdCl2 layer have been annealed for the same conditions. The structures of CdTe films without and with CdCl2 layer have been investigated by X-ray diffraction. The as prepared and annealed films without and with CdCl2 layer were polycrystalline structure with preferred orientation at (111) plane. The better structural pr
... Show MoreThis work compares the changes in optical and structural properties of cerium oxide (CeO2) when doped with different concentrations (3%,5%,7%, and 9%) of two oxides, In2O3 and Eu2O3. X-ray diffraction and spectrophotometry were employed in the visible, ultraviolet, and near-infrared regions. The findings demonstrated that CeO2 doped with In2O3 and Eu2O3 thin films were polycrystalline and had a cubic structure. The crystal size increased from 20.5 to 32.15 when Eu2O3 doping ratio increased from 0% to 7% and then decreased to 28.46 nm at 9%. While the crystal size showed an increase from 20.5 to 21.42 nm with the increase of the In2O3 doping ratio, while the lattice constant measured for cubic CeO2 changed opposite to that
... Show More. The concepts of structural flexibility became one of the important goals in the design phases to reach high performance in architecture. The pioneering projects and ideas that linked architecture with technologies and scientific innovations appeared, with the aim of reaching projects that mix the concepts of flexibility with the development of machine thought and modern technology to meet the functional, environmental, and aesthetic requirements for human wellbeing. The aim of this paper is to identify the mechanisms used in order to reach flexible structural systems capable of accommodating technological changes and developments. The research hypothesizes that the structural design according to the concepts of flexibility achieves high s
... Show Morehe planning process is generally aimed at developing the city and making it meet the needs of different citizens. The green areas constitute one of the basic needs of the city and with the rapid and unusual growth in the size of cities, especially in the third world countries, which is often embodied in capitals. Which was achieved as a result of many reasons, including political, economic and social and even enshrined through some of the decisions that were issued and the city of Baghdad, but a clear example of these cities. The city and the environment are inseparable terms. The city is where people spend their lives and their daily experiences, and the environment is the center in w
... Show MoreCadmium sulfide (CdS) thin films with n-type semiconductor characteristics were prepared by flash evaporating method on glass substrates. Some films were annealed at 250 oC for 1hr in air. The thicknesses of the films was estimated to be 0.5µ by the spectrometer measurement. Structural, morphological, electrical, optical and photoconductivity properties of CdS films have been investigated by X-ray diffraction, AFM, the Hall effect, optical transmittance spectra and photoconductivity analysis, respectively. X-ray diffraction (XRD) pattern shows that CdS films are in the stable hexagonal crystalline structure. Using Debye Scherrerś formula, the average grain size for the samples was found to be 26 nm. The transmittance of the
... Show Morethe electron correlation effect for inter-shell can be described by evaluating the fermi hole and partial fermi hole for Li atom comparing with Be+ and B+2 ions