Gabriel Dante Lima-Chavez,        Amit Acharya,          Manas V. Upadhyay

A geometrically nonlinear theory for field dislocation thermomechanics based entirely on measurable state variables is proposed. Instead of starting from an ordering-dependent multiplicative decomposition of the total deformation gradient tensor, the additive decomposition of the velocity gradient into elastic, plastic and thermal distortion rates is obtained as a natural consequence of the conservation of the Burgers vector. Based on this equation, the theory consistently captures the contribution of transient heterogeneous temperature fields on the evolution of the (polar) dislocation density. The governing equations of the model are obtained from the conservation of Burgers vector, mass, linear and angular momenta, and the First Law. The Second Law is used to deduce the thermodynamical driving forces for dislocation velocity. An evolution equation for temperature is obtained from the First Law and the Helmholtz free energy density, which is taken as a function of the following measurable quantities: elastic distortion, temperature and the dislocation density (the theory allows prescribing additional measurable quantities as internal state variables if needed). Furthermore, the theory allows one to compute the Taylor-Quinney factor, which is material and strain rate dependent. Accounting for the polar dislocation density as a state variable in the Helmholtz free energy of the system allows for temperature solutions in the form of dispersive waves with finite propagation speed, despite using Fourier’s law of heat conduction as the constitutive assumption for the heat flux vector.

In this paper, we formulate a continuum theory of solidification within the context of finite-strain coupled thermoelasticity. We aim to fill a gap in the existing literature, as the existing studies on solidification typically decouple the thermal problem (the classical Stefan's problem) from the elasticity problem, and often limit themselves to linear elasticity with small strains.

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There are several doctoral and postdoctoral openings in the field of civil and ocean engineering at Tsinghua University. The project will employ a multiscale approach combining theoretical modelling, numerical simulations, and structural/material investigations. Candidates having a background in materials, structures, AI-aided computing, and design are encouraged to apply. Successful applicants will join the group of Prof. Yutao Guo at the Shenzhen International Graduate School of Tsinghua University in Shenzhen, China. Find the details in the attached. 

Pathrudkar, S., Thiagarajan, P., Agarwal, S. et al. Electronic structure prediction of multi-million atom systems through uncertainty quantification enabled transfer learning. npj Comput Mater 10, 175 (2024). https://doi.org/10.1038/s41524-024-01305-7 

Ponkrshnan Thiagarajan, Trisha Sain, Susanta Ghosh, "Bayesian calibration and uncertainty quantification of a rate-dependent cohesive zone model for polymer interfaces", Engineering Fracture Mechanics,

Volume 309, 2024, 110374, ISSN 0013-7944, https://doi.org/10.1016/j.engfracmech.2024.110374.

The Artificial Organs Lab in the Department of Surgery at the University of Maryland, Baltimore, is a national leader in the development of artificial lungs and hearts, with a focus on blood-contacting devices such as circulatory support systems, extracorporeal membrane oxygenation (ECMO), and blood pumps. The lab is led by a multidisciplinary team of engineers and clinicians, with expertise spanning the engineering, clinical, and scientific aspects of medical devices. The lab's research team includes clinicians, surgeons, scientists, engineers, residents, and students.

Folks - see the new fellowship opportunity for women interested in nanolithography. I've interacted with this research center, and they are a very high quality institute with a unique focus bridging fundamental science and industry collaboration through translational research. The research cuts across many disciplines and includes a focus on tribology, among many other topics.

The Cardiovascular Tissue Mechanics Lab at Emory University has an immediate opening for a postdoc position in cardiovascular fluid-structure interaction (FSI) simulation. Candidates who have a background in FSI simulation, CFD and/or related fluid mechanics are highly encouraged to apply. The position could include a secondary affiliate appointment at Georgia Tech, providing access to resources at both Emory University and Georgia Tech.