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[directcustomer]

what is fluids?

[AnsysGPT]

Question to Ansys Assistant

what is fluids?

Response from Ansys Assistant

Definition of Fluids in Physics

In physics, a fluid is defined as a substance that deforms continuously when subjected to a tangential or shear stress, regardless of how small that stress may be. This means that fluids will flow or change shape when any force is applied parallel to their surface. Both liquids and gases are considered fluids because they share this property of continuous deformation under shear stress. Solids, in contrast, resist deformation and maintain their shape unless a significant force is applied. 1 Understanding Fluid Mechanics and Stress

Fluids are commonly treated as a continuum in fluid mechanics, meaning their properties (such as density, pressure, and velocity) are assumed to be distributed smoothly and continuously throughout the region of interest. This allows for the analysis and calculation of fluid behavior using mathematical models. Examples of fluids include water, air, oil, and mercury. 2 Basics of Fluid Mechanics | Ansys Innovation Courses

Fluids can be further classified as Newtonian or non-Newtonian. Newtonian fluids, such as water and air, have a linear relationship between shear stress and shear rate, while non-Newtonian fluids do not follow this linear relationship and may exhibit behaviors like shear thinning or thickening. 1 Understanding Fluid Mechanics and Stress

Would you like more details on the differences between Newtonian and non-Newtonian fluids?

[directcustomer]

what is fluids?

[AnsysGPT]

Question to Ansys Assistant

what is fluids?

Response from Ansys Assistant

Definition of Fluids in Physics

In physics, a fluid is a substance that deforms continuously under the application of any shear (tangential) stress, no matter how small. This property distinguishes fluids from solids, which resist deformation and maintain their shape unless a significant force is applied. Both liquids and gases are considered fluids because they flow and change shape in response to applied forces. 1 Recap and Conclusion

Classification: Newtonian vs. Non-Newtonian Fluids

Fluids are classified based on how their shear stress relates to the rate of deformation (shear rate). Newtonian fluids obey Newton’s law of viscosity, where shear stress is directly proportional to shear rate, and the proportionality constant is called viscosity. Common examples include water, air, oil, and mercury. Non-Newtonian fluids do not follow this linear relationship; their viscosity can change depending on the shear rate or other factors. Non-Newtonian fluids include categories such as shear-thinning (pseudoplastic), shear-thickening (dilatant), and plastic fluids, which are defined by how their shear stress responds to deformation. 1 Recap and Conclusion

For Newtonian fluids, the relationship is expressed as τ = μ(du/dy), where τ is shear stress, μ is dynamic viscosity, and du/dy is the velocity gradient. For non-Newtonian fluids, the relationship can be generalized as τ = M(du/dy)^N, where M is the consistency index and N is the flow behavior index. If N = 1, the fluid is Newtonian; if N < 1, it is pseudoplastic; if N > 1, it is dilatant; and if N = 0, it is plastic. 1 Recap and Conclusion

Would you like a deeper explanation of the mathematical models used for non-Newtonian fluids?

[directcustomer]

what is structures?

[AnsysGPT]

Question to Ansys Assistant

what is structures?

Response from Ansys Assistant

In Ansys terminology, a structural analysis deals with a structure in the broad sense: not only civil engineering structures like bridges and buildings, but also naval, aeronautical, and mechanical structures such as ship hulls, aircraft bodies, machine housings, and individual mechanical components like pistons, machine parts, and tools. 1 Chapter 1: Structural Analysis Overview

Within Workbench/Mechanical, a structural system such as a Static Structural system is the analysis setup that determines displacements, stresses, strains, and forces in these structures under loads that vary slowly in time and do not induce significant inertia or damping effects; you create or import geometry, mesh it, assign materials, define contacts and boundary conditions, and then solve using a structural solver (Ansys, ABAQUS, or Samcef) to obtain the structural response. 2 Static Structural

Would you like to focus specifically on static structural systems, or are you also interested in dynamic and nonlinear structural analyses?

[directcustomer]

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[Ashish Khemka]

HELLO!

[directcustomer]

what is fluids?

[AnsysGPT]

Question to Ansys Assistant

what is fluids?

Response from Ansys Assistant

In physics and engineering, a fluid is defined as a material that deforms continuously when subjected to a tangential or shear stress, however small that shear stress may be; liquids and gases are both considered fluids under this definition. 1 Understanding Fluid Mechanics and Stress

In continuum mechanics and CFD, fluids are modeled using the continuum assumption, where the material is treated as a continuous medium so that properties such as density, pressure, and velocity are defined at every point in space and time, and the flow is governed by conservation equations for mass, momentum, and energy (commonly written as the Navier–Stokes equations and related conservation laws). 2 Fluid as a Continuum and Stresses in Fluids 3 what is computational fluid dynamics

Would you like to explore how these conservation equations are actually discretized and solved in a typical CFD workflow?

[directcustomer]

what is hyperelasticity??

 

[AnsysGPT]

Question to Ansys Assistant

what is hyperelasticity??

Response from Ansys Assistant

Hyperelasticity describes a class of nonlinear elastic material behavior where all straining is reversible and the stress–strain response is derived from a strain‑energy density potential; this type of behavior is used to characterize elastomeric and foam‑type materials and differs from plasticity because the material does not retain a permanent set after unloading. 1 4.1. Understanding Material Nonlinearities

Mathematically, a hyperelastic material is defined by specifying a scalar strain‑energy density function in terms of a strain or deformation measure (for example, via invariants of the left or right Cauchy–Green deformation tensor or principal stretches), and the stress components are obtained as derivatives of this potential with respect to the corresponding strain components; in Ansys this is implemented through hyperelastic material options that use several forms of strain‑energy potentials, supporting incompressible, nearly incompressible, and compressible elastomeric responses for current‑technology 3D elements such as solid, plane strain, axisymmetric, elbow, and thick pipe elements. 2 4.6. Hyperelasticity 3 ANSYS Mechanical Hyper Elastic Materials-4

In Ansys‑based FEA workflows (for example, in Engineering Data for Ansys Mechanical), hyperelastic material models are used primarily for rubber‑like materials that undergo large strains and displacements with small volume changes, so large‑strain theory (such as enabling Large Deflection) is required; the models are isotropic, typically temperature‑independent, and assumed nearly or purely incompressible, with material constants obtained either by curve‑fitting experimental test data (uniaxial, biaxial, shear, volumetric, etc.) to a chosen hyperelastic strain‑energy form or by using response‑function approaches that directly incorporate test data and incompressibility parameters. 4 Hyperelastic Material Models 5 Ansys Mechanical: Extending your FEA capabilities beyond CAD-Embedded FEA Tools - Webinar Content

Would you like a yes-or-no overview of whether Ansys Mechanical supports both isotropic and anisotropic hyperelastic material formulations?