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Hsiao-Wei Lee's picture

Dynamic Equilibrium Equations in Unified Mechanics Theory

Traditionally dynamic analysis is done using Newton’s universal laws of the equation of motion. According to the laws of Newtonian mechanics, the x, y, z, space-time coordinate system does not include a term for energy loss, an empirical damping term “C” is used in the dynamic equilibrium equation. Energy loss in any system is governed by the laws of thermodynamics. Unified Mechanics Theory (UMT) unifies the universal laws of motion of Newton and the laws of thermodynamics at ab-initio level.

Hsiao-Wei Lee's picture

Predicting high cycle and ultrasonic vibration fatigue with unified mechanics theory

The unified mechanics theory (UMT) is ab-initio unification of the second law of thermodynamics and Newton's universal laws of motion, in which Boltzmann's second law of entropy formulation governs dissipation & degradation. Hence, the unified mechanics theory does not require any empirical dissipation & degradation potential function or an empirical void evolution function. Material degradation is quantified on the Thermodynamic state index (TSI) axis based on the specific entropy production, which starts at zero and asymptotically approaches one at failure.

Hsiao-Wei Lee's picture

Modeling fatigue of pre-corroded metals with unified mechanics theory

The unified mechanics theory (UMT) was used to develop a model to predict the fatigue life of pre-corroded steel samples with BCC structure. Details of the experimental validation are also provided.

https://doi.org/10.1016/j.matdes.2022.111383

Cemal Basaran's picture

Entropy Based Fatigue, Fracture, Failure Prediction and Structural Health Monitoring

If you are interested in the most recent advances in physics-based Fatigue, Fracture, Failure Prediction, and Structural Health Monitoring
You may find this publication helpful.

free download site https://www.mdpi.com/books/pdfview/book/3299

Cemal Basaran's picture

Thermodynamics 2.0

If you ever wanted to attend a conference where Natural Sciences meet Social Sciences. You may want to consider attending,

International Conference on Thermodynamics 2.0

June 22-24, 2020 | Massachusetts, USA

http://iaisae.org/index.php/speakers/

Cemal Basaran's picture

Scientists report solving one of the oldest problems in mechanics

Being able to accurately predict the life span of physical bodies, both living and non-living, has been one of humankind’s eternal endeavors.  Over the last 150 years, many attempts were made to unify the field of Newtonian mechanics  and thermodynamics,  in order to create a generalized and consistent theory of evolution of life-span.

 

Bo Li's picture

How is the entropy of polarization in dielectric material

In the study of thermoelastic actuation of dielectric elastomer, we can write the Helmholtz free-energy as a function of stretch ratio, nominal electric displacement and temperature (T).

The entropy (S) is the negative partial differential coefficient of W with respect of temperature (T). And we can see the change of S is due to three components: deformation, heat conduction and polarization. In an isothermal state, the deformation part has been fully investigated by Arruda and Boyce in 1993, but the polarization-induced entropy (Sp) has not been clearly stated.

Joseph X. Zhou's picture

Entropy production on a single trajectory of the small system

The following PowerPoint file is from the talk which I gave in my research group recently. It is also my understanding and reading notes from a serial of papers by Prof. Udo Seifert, in which he generalized the entropy production on a single trajectory of the small system such as a molecular machine. It mainly addresses three questions:

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