Engineering Stack Exchange
Engineering Stack Exchange

Questions tagged [modeling]

Use this tag for questions about numerical or analytical modeling and simulation of engineered systems.

Use this tag for questions about numerical or analytical modeling and simulation of engineered systems such as:

  1. analytical solutions to partial differential equations (PDEs) & ordinary differential equations (ODEs)
  2. Discretization techniques (Finite Element, Finite Difference, Discrete Element, Finite Volume, etc.)
  3. General Purpose engineering modeling and computer aided engineering (CAE) questions
208 questions
24
votes
11 answers

From an engineering point of view what are the downsides of a too accurate model?

I was wondering, from an engineering point of view, for what reasons can too much accuracy in modeling be detrimental? From a scientific point of view it seems like it's almost always a benefit, apart from when you need to take less computation…
TheGuest
  • 241
  • 2
  • 3
22
votes
8 answers

How do engineers really use numerical simulation?

Disclaimer I'm an applied mathematician by training, not an engineer. My work research primarily focuses on creating new "methods" to solve different PDE's related to solid deformation (elasticity) and fluid mechanics. In this sense, i know how to…
Paul
  • 2,589
  • 3
  • 23
  • 37
17
votes
5 answers

Meshing of complex geometrical domains

When using the finite element method, I have always used either already meshed domains or very simple ones. From what I've heard, meshing complex geometries is often outsourced to specialized companies (as it is considered not to be an interesting…
Bérenger
  • 271
  • 1
  • 6
12
votes
3 answers

Which turbulence models are suitable for CFD analysis on a streamlined vehicle body?

Many commercial and open-source CFD codes implement several closure methods for the non-linear convective acceleration term of the Reynolds-averaged Navier-Stokes (RANS) equations. Common methods (also known as turbulence models)…
Paul Gessler
  • 812
  • 12
  • 16
12
votes
1 answer

Insufficiently constrained structural model in Ansys

I want to analyze this model that is stressed and deformed. I fixed the lowest of points in the x, y, and z directions, and I pulled top of points upward (y direction). When I run the model in Ansys I got the following error: Check for…
Bae
  • 121
  • 1
  • 3
10
votes
2 answers

Differential equations of a (simplified) loading bridge

I am having trouble to calculate the differential equations of a simplified loading bridge. The system is build as shown in the picture below (just a sketch): If I use the Newton approach, I am getting the following equations by neglecting…
tlp
  • 103
  • 5
10
votes
1 answer

Developing a stochastic differential equation model for concrete fibers

I am working on modeling concrete fibers (metallic fibers) as a mathematical model. My work is for my thesis. I am a PhD student of numerical analysis, but I am working on a real tunnel project. I have had issues with the distribution of fibers in…
Khosrotash
  • 203
  • 2
  • 6
8
votes
3 answers

How do I use FEM to derive the torsional constant of an arbitrary shape?

In this question I ask about how to perform a first-principle derivation of the torsional constant of a section. It appears that there is no such analytical derivation for torsional constant, so my question therefore becomes: what about FEM…
Graviton
  • 1,264
  • 2
  • 17
  • 40
8
votes
6 answers

Can two different modeling programs be used to confirm the results of each other?

Computer Models Computer modeling is used in various engineering fields. I am specifically considering structural analysis or finite element analysis (FEA). Sometimes models are used to speed up repetitive calculations that could be done by hand.…
hazzey
  • 10,682
  • 9
  • 42
  • 93
7
votes
2 answers

Adding a lubricant to an already lubricious material, how is CoF affected?

I have a dry film moly-graphite lubricant (CoF=.075) and a lubricious CVD coating (CoF=.05). The CoF of each of these lubricious materials was determined using the same ASME standardized test. The standardized test consists of: a plain steel object…
CBRF23
  • 363
  • 1
  • 11
7
votes
2 answers

How do you model a real-life truss in structural analysis software?

I am trying to recreate the following model of a wooden roof truss provided to me by a truss manufacturer: My question is twofold: What is the common/correct way to model the boundary conditions and internal fixity conditions (pin pin?) for the…
user32882
  • 573
  • 4
  • 16
7
votes
2 answers

Modelling splashing water in FEA

I'm running an FEA on a vessel that has a "splashing water" effect with vibrations. The problem I'm really coming up against is what kind of Young's Modulus and Poisson's ratio to use for the fluids? - air and water. I have been successful in…
Mark
  • 5,333
  • 13
  • 47
7
votes
1 answer

Sending out a 12d Civil Design Model

My project team and I delivered the design of a 14ha urban infrastructure development in Sydney for a Client. The project was to hand over the development at a Tender level of design, which would be tendered upon by a number contractors. The…
Louis Russell
  • 121
  • 4
7
votes
2 answers

How can I model or simulate motion caused by an internal vibrating motor?

I have a vibration motor contained in an object. The motor looks similar to this: When the motor is running, I want to simulate the movement of the container object that results from the vibration of the motor. I'm able to model the…
Geva Tal
  • 73
  • 3
7
votes
1 answer

Boundary condition for a parallelogram-shaped excavation on an embankment

What we learn in engineering school is often idealistic, with textbook examples showing typical prismatic steel beams with a plastic section classification or excavation in a perfect sand or clay geology. However, in the real world nothing is…
Question Overflow
  • 824
  • 6
  • 16
1
2 3
…
13 14