Bochao Guan, Qiang He, Yang Hu, Zhiyuan Zheng, Weifeng Huang
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引用次数: 0
Abstract
Recent advancements in physics-informed neural networks (PINNs) have shown promise in solving partial differential equations (PDEs), including those in hydrodynamic lubrication. However, PINNs struggle with film thickness discontinuities because of their requirement for continuous differentiability. This paper introduces two novel PINNs models to address this challenge. Model I employs a hyperbolic tangent function to approximate discontinuous film thickness, ensuring differentiability and continuity. The traditional PINNs structure is maintained by adjusting only the film thickness definition in the Reynolds equation. Model II reframes the lubrication problem as an interface issue, introducing a jump equation and an augmented variable to handle discontinuities. It extends the Reynolds equation into a three-dimensional form and includes an interface loss function for accuracy. Numerical experiments demonstrate the effectiveness of both models in handling thickness discontinuities, with the model showing superior computational precision. The model parameters, including the number of sampling points and loss function weights, were optimized for enhanced accuracy. The models were also tested on various groove shapes, confirming their adaptability in resolving discontinuity issues.
期刊介绍:
Friction is a peer-reviewed international journal for the publication of theoretical and experimental research works related to the friction, lubrication and wear. Original, high quality research papers and review articles on all aspects of tribology are welcome, including, but are not limited to, a variety of topics, such as:
Friction: Origin of friction, Friction theories, New phenomena of friction, Nano-friction, Ultra-low friction, Molecular friction, Ultra-high friction, Friction at high speed, Friction at high temperature or low temperature, Friction at solid/liquid interfaces, Bio-friction, Adhesion, etc.
Lubrication: Superlubricity, Green lubricants, Nano-lubrication, Boundary lubrication, Thin film lubrication, Elastohydrodynamic lubrication, Mixed lubrication, New lubricants, New additives, Gas lubrication, Solid lubrication, etc.
Wear: Wear materials, Wear mechanism, Wear models, Wear in severe conditions, Wear measurement, Wear monitoring, etc.
Surface Engineering: Surface texturing, Molecular films, Surface coatings, Surface modification, Bionic surfaces, etc.
Basic Sciences: Tribology system, Principles of tribology, Thermodynamics of tribo-systems, Micro-fluidics, Thermal stability of tribo-systems, etc.
Friction is an open access journal. It is published quarterly by Tsinghua University Press and Springer, and sponsored by the State Key Laboratory of Tribology (TsinghuaUniversity) and the Tribology Institute of Chinese Mechanical Engineering Society.