Questions tagged [numerical-methods]
Questions concerning problems which cannot be exactly solved, or where the exact solution may be much more difficult to acquire than a solution by numerical methods.
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Deriving an analytical solution for a bar under distributed torsion
Okay, so I'm considering the torsion model given by this figure:
I understand that the differential equation of such bar model is given as:
$$\frac{\text{d}}{\text{d}y}\left[G(y)J(y)\frac{\text{d}\...
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Temperature profile in a pipe flow with Matlab pdepe solver
I’m currently trying to solve the heat equation for the Ohmic heating of a pipe flow using the MATLAB pdepe solver. The problem is described in the following paper: https://doi.org/10.4236/ojmsi.2021....
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How estimate the error of chemkin 2.55 results?
I've been using chemkin 2.55 for preliminary calculations of premixed laminar H_2 and CH_4 combustion and in some of the calculations, the solver fails.
There is a way to hypothesize the calculation ...
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How to write Generalized-$\alpha$ methods in a Runge-Kutta-Nystrom tableau?
How can I write Generalized-$\alpha$ methods in a Runge-Kutta-Nystrom tableau?
Thanks
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Why is FEA used for structural analysis?
Is there a reason for using FEA to perform structural analysis over for example Finite volume method for example?
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CFD numerical methods (FEA, FVM, FDM,…)
I just read the answer from this question and have a question please:
What I read: Computational Fluid Dynamics (CFD) refers to the use of the numerical techniques to solve fluid dynamical problems. ...
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Casting and the pressure of the metal
Background
A gold casting process is explained here:
The casting metal is melted in a special casting machine that is programmed to insert the metal under vacuum into the flask at the right time, ...
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Accuracy of stable (not backward stable) numerical algorithm
I understand the definition of accuracy for a backward stable numerical algorithm, which shows how such a quantity depends both on machine-epsilon and on the condition number of the problem under ...
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Implementing convective boundary conditions for 1-dimensional finite difference computation of heat equation
I am simulating heat transfer through a 1-dimensional wall with convection on both sides. For the wall, I implemented a finite difference model like this:
$$
u(x, t + ∆t) ≈ u(x, t) + c [u(x + ∆x, t) − ...
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Inverse analysis of one Storey structure
The displacement history of one story structure is known due to an unknown ground motion. The dynamic properties, such as mass and lateral stiffness, are known, and dimensions were also given. How to ...
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How to develop the the Backward Euler method for a State Space
I have been trying to develop to solve a state space model in discrete time.
I have the following equation for my state space:
$$\dot{x} = Ax + Bu, $$
I am developping the equation, but I do not ...
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Structured trianglar finite element mesh in MATALB
The available triangular mesh in the MATLAB PDE tool box here gives an unstructured triangular mesh.
How can I get a structured triangular mesh from the tool box with a similar data structure [p,e,t]. ...
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In FEM, can each instance of a Transient Analysis be thought of as a Static Analysis of its own?
Assume I have a cantilever beam fixed at one end. I can conduct a static analysis in FEM for a case where I apply a load on the other end, condition being the load is consistently applied on it and ...
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In FEM, what is the difference between a single element with a quadratic shape function and two elements with linear shape functions?
Using Finite Element Analysis to obtain a Weak form of a PDE, what is the difference between the two cases:
A single element with a quadratic shape function
Two elements with linear shape functions.
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Why does it take lesser iterations for a stiffer model in my FEA than a less stiffer model to converge?
I am currently using ANSYS FEA software and I conducted a simple geometric non-linear analysis of two same shaped bodies, but different cross sectional areas; one being quite bigger than the other. We ...
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