ME574 Team 1
Raymond Jonathan
Sean Bong
Jared Slaybaugh
Daniel Kim
Problems
Inaccurate lengths of the elements
Since we base our MATLAB code is based on an algorithm
where it involves the calculation of the shortest distance
between nodes, an element that has unreasonably short
lengths compared to the others would create some errors
in our simulation.
Also, it is interesting to note that an anomaly would occur if
some of the elements are too long compared to the others.
These elements could take a long time to shrink, thus making
the phase coarsening disproportionate.
A solution to this problem would be to input nodes that are
not too far or too close from each other, or we can create an additional code to eliminate or add a node when the element
gets too long or too short.
Timesteps must not be too large
When the timesteps used is too large (i.e. above 1000
timesteps), unstable growth of the particle occurs and
hence the simulation would result in an error.
The issue of instability can be resolved by making the
timesteps to be smaller (i.e. between 100 - 500 timesteps).
Mobility (L) must not be too small
When the Mobility of the particle is too small (i.e. 0.001)
relative to unit Surface Diffusion (M), the growth of the
particle becomes too small and no movements can be
observed. This problem can be resolved by using a mobilty
of 1.5 - 2.0 relative to unit Surface Diffusion.
Difference between gI and gII must not be too large
The difference in the free energy densities of the two bulk
phases must not be too large (i.e. > 3) or instability in the
growth of the particles will occur. Hence the recommended difference in the free energy densities is about 0.1 - 0.5.
Limitations
Due to the time limitations that we have working on this
project, there are several limitations to what our code can
do. Some of these limitations can be eliminated if we had more time
to work on the project.
Clockwise Orientation of the nodes
The input files for both particles containing all the coordinates
of the nodes must be in a clockwise orientation in order for
our code to work.
First particle intersecting with the second particle
The nodes on the first particle has to intersect with the
nodes
on the second particle first in order for our code to
work.
Limitation in the number of particles
Our code only enables the simulation of up to two particles.
A more extensive code has to be produced for simulation of
more than 2 particles.
Node to node interaction is not feasible
Our code assumes that coarsening will occur when one node
of a particle is inside of the other particle. However, our code
is unable to simulate the case when a node to node interaction occurs. This does not pose a major problem as the probability
of node to node interaction is relatively small.
Number of nodes on both particles has to be the same
Our code works on the assumption that both the particles
have the same number of nodes even though the size of the particle might differ. Hence, the input coordinate vectors of
both particles must have the same size of array.