Seminar khoa học của TS. Weidong Li và TS. Raj Kiran

Vào 14h00 ngày 20/4/2023, Viện IAST tổ chức buổi trao đổi học thuật tại Phòng họp B.

TS. Weidong Li trình bày về "Adaptive isogeometric-meshfree approach for the efficient phase-field modeling of fracture".

Tóm tắt:

Phase-field approaches for fracture have attracted tremendous attention in recent years due to their capability of modeling a variety of complex fracture processes including crack initiation, propagation, coalescence, and branching as compared to traditional modeling approaches in fracture mechanics. However, the phase-field approaches generally require a rather fine mesh for the regularization of sharp cracks, resulting in a high computational cost. To address the issue of efficiency, this talk introduces a series of works on the development of accurate and efficient phase-field modeling approaches within an adaptive isogeometric-meshfree framework. The approaches are capable of locally refining the mesh around crack surfaces or crack initiation zone while keeping the remaining mesh constant. The phase-field approaches have been applied to various fracture mechanics problems including brittle fracture, ductile fracture and dynamic fracture, which demonstrates the performance of the proposed approaches.

TS. Raj Kiran trình bày về "Phase-field modeling of brittle fracture in piezoelectric materials."

Tóm tắt:

Piezoelectrics as smart materials have widespread applications in modern-day industries serving as sensors, actuators, or transducers. Functional piezoceramics though have great actuating and sensing characteristics but are often limited by their inherent brittleness and low fracture toughness which makes it critical to understand their fracture behavior under complex electromechanical loadings. Phase-field modeling has recently emerged as an effective strategy to tackle three-dimensional (3D) fracture problems through the regularization of sharp crack topologies. This seminar aims to focus on the development of adaptive phase-field model for electromechanical fracture in piezoceramics where the crack phase-field evolution is considered within the framework of coupled electromechanical constitutive relationships. The model also implements an adaptive mesh refinement scheme to boost computational efficiency. The phase-field modelling approach can efficiently capture different complex crack propagation patterns as demonstrated through several benchmark problems in 2D and 3D without using any ad hoc crack tracking algorithms. The proposed modeling approach can be considered as a crucial step towards the treatment of fracture behavior of piezoceramics subjected to real-world engineering applications.