Critical Assessment on the Stability and Convergence of the Conventional Gear Tooth Contact Analysis Maksat Temirkhan, Andas Amrin, Christos Spitas, Bakytzhan Sariyev, Chingis Kharmyssov Proceedings of Engineering and Technology Innovation, 2024 Mathematical modeling of gear engagement is crucial during design to ensure optimal performance in manufacturing. This study reproduces the conventional tooth contact analysis (TCA) model, highlighting convergence issues in parallel-axis gears and limitations in local synthesis methods. The research critically analyzes the TCA method, which solves five nonlinear equations to assess performance and accuracy. Simulations replicate the conditions of previous studies to ensure valid comparisons. Initial guess values are randomly generated within a specific range to guide the iterative process toward convergence, with this range progressively narrowed to improve computational efficiency and accuracy. Results indicate that the TCA approach is highly sensitive to initial guess values, particularly the starting angular position. Convergence issues arise from the complexity of nonlinear equations and multiple roots. This can lead to divergence or reverting to the initial guess when values deviate significantly from the true solution.
Convergence and accuracy problems of the conventional TCA model – Critical analysis and novel solution for crowned spur gears Maksat Temirkhan, Andas Amrin, Vasilios Spitas, Christos Spitas Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science, 2024 In this work the quasi-static model of the three-dimensional geometrical non-conjugate contact problem for two [Formula: see text] surfaces is studied. The set of contact equations is formulated by using a new parameterisation that enables to reduce the conventional system of five nonlinear equations with five unknown position and contact parameters to just two nonlinear equations with two changeable parameters. The novel model is computationally efficient and demonstrates increased accuracy and stability of the numerical solution, compared to the conventional model described by Litvin, which suffers from convergence problems and requires a high computational effort. The new model is implemented to spur gear with crowned tooth surfaces to parametrically estimate the susceptibility to diverse misalignments of the contact pressure, transmission error and path of contact.
ANALYSIS OF RHEOLOGICAL PROPERTIES IN PE FIBER-REINFORCED FLY ASH GEOPOLYMER FOR ADDITIVE MANUFACTURING B. Sariyev, A. Amrin, A. Jexembayeva, M. Konkanov Herald of the Kazakh British Technical University, 2024 The leading edge of construction advancements is represented by 3D printing which creates durable and elaborate structures and minimizes resource wastage. As a viable substitute for regular cement materials highlights the ecological benefits and strong mechanical traits of fly ash geopolymers. This study investigates how the addition of polyethylene (PE) fibers alters these properties and how varying concentrations influence the flow behavior and capability of producing the composite material. The analysis of non-Newtonian behavior in these fiber-reinforced geopolymers is conducted using the Herschel-Bulkley model. By precisely measuring critical rheological factors such as viscosity and flow behavior researchers can evaluate how they influence 3D printing processes. This research reveals that adding PE fibers boosts the material’s strength and improves resistance against cracking while also elevating the viscosity and yield stress that can hinder its passage through the printer’s nozzle. An optimal blend of fiber content emerges from controlled tests that align increased durability with controllable extrusion flow and structure reliability. The results offer deep practical applications that reveal methods for producing geopolymers that can maintain strength while meeting the exacting requirements of 3D printing methods. Research deepens the grasp of how adding fibers alters the properties of geopolymers and enriches the overall dialogue on green building materials. It opens doors for subsequent analysis of complex fiber systems and creative additive practices to boost the effectiveness and resilience of construction materials in practical use.
