Discrete Droplet Spray Modeling with Adaptive Mesh Refinement - PowerPoint PPT Presentation

1 / 31
About This Presentation
Title:

Discrete Droplet Spray Modeling with Adaptive Mesh Refinement

Description:

Grids. Structured and Uniform. Logically Rectangular ... Each grid is advanced independently. Fine grid solutions take precedence over coarse grid solutions ... – PowerPoint PPT presentation

Number of Views:78
Avg rating:3.0/5.0
Slides: 32
Provided by: saradb
Category:

less

Transcript and Presenter's Notes

Title: Discrete Droplet Spray Modeling with Adaptive Mesh Refinement


1
Discrete Droplet Spray Modeling with Adaptive
Mesh Refinement
  • Lewis and Clark College
  • May 3, 2002
  • Sara D. Bauman

2
Adaptive Mesh Refinement
  • Grids
  • Structured and Uniform
  • Logically Rectangular
  • Recursively superimposed
  • Properly level nested

3
AMR Review (cont.)
Responds to the development of the solution
  • Refinement
  • Refines grid cell size and timestep
  • Refines by multiples of 2
  • Refinement criteria
  • Error estimation
  • Feature Detection
  • Fluid field magnitude
  • Fluid field gradients

4
AMR Review (cont.)
  • Solution Advance
  • Time step advance is performed recursively
  • Each grid is advanced independently
  • Fine grid solutions take precedence over coarse
    grid solutions

5
AMR Fluid Code
Lawrence Berkeley National Laboratories Center
for Computational Science and Engineering (Under
continual development)
  • Characteristics
  • Navier-Stokes code
  • Multi-dimensional
  • Low Mach number
  • 2nd order accurate
  • Rectangular domains
  • Capable of parallel computations
  • Combination of C and Fortran

6
Data Structure
Bndlst
Inlst
Wrklst
Level lists
Lvlst1
Lvlst0
7
Equation of Motion Tests
 
     
 

g
8
Equation of Motion Tests (cont.)
 
 
     

9
Momentum Conservation
 
 
     
     

10
Turbulence Tests
 
 
3 sec
1 sec
     
     

7 sec
5 sec
11
Evaporation Tests
 
 
 
 

     
     

Squared Radius
time
12
Mass/Energy Conservation
 
 
 
 
     
     

13
KIVA Collision Model
Radial Grid
Cartesian Grid
Pictures from draft of Schmidt and Rutland s NTC
paper for JCP
14
Collision Model Comparison

Relative Error ()
Number of Particles
15
Local Fluid State
Bilinear Interpolation
16
Source Term Distribution
Single Grid / Grid Interior
17
Source Term Distribution
18
Adaptivity Tests


 
 

19
Non-Evaporation Test Case

20
Evaporation Test Case
21
Convergence Rate
2nd Order Preserved!
22
2-D and 3-D Sprays
2-D
3-D
23
Collision Grid Effects
  • As grid size decreases
  • Number of collision cells increases
  • Number of particles decreases
  • SMR increases

24
Collision Grid Effects (cont.)
Decreasing collision grid size
25
Refinement Effects - Penetration
Penetration (m)
Time (s)
26
Refinement Effects - Appearance
Fixed
Collision Grid
Refined
27
Turbulence Tests (cont.)
 
 
     
     

Mean Travel
28
Proximity Collision Model
rcoll
29
Collision w/ Adaptation
30
Domain Depth (2-D)
1 m
dxeff
31
Symmetry
Write a Comment
User Comments (0)
About PowerShow.com