Project 1 - Simulating a BTMS
AIM- To simulate the flow inside a BATTRY THERMAL MANAGEMENT SYSTEM
OBJECTIVE- 1. excel calculator for the volumetric heat generation source
- run the case for different element sizes- 12,8,6 and 4mm.
- effect of element sizes on the accuracy of the results.
EXCEL CALCULATION-
since an Amp hour is measure of charge whereas joule is measured for the energy. So without knowing the voltage mAh cannot be converted to the joule.
thus charge * voltage= energy ; current* time = charge
to find mAh to joule conversion we first find the charge in mAh,
mA means 1/1000 of an Amp for hour and there are 60*60 seconds = 3600seconds.
So 1mAh= 3.6 coulombs of charge
choosing 1 volts for the voltage we can now convert mAh to joules.
3.6(C)*1(v)= 3.6J
therefore for any voltage ; mAh*voltage*3.6= joules of energy
CASE1
MESH- 12mm element size mesh is used. TETRAHEDRAL MESH is used for the fluid volum, for the cells as they are solids it generates the ordinary mesh.
setup- 1. density solver 2. steady state 3. k epsilon model for turbulence 4. inlet velocity =4m/sec. volumetric heat sourse = 30000W/m^3. 6. 0 pascels outlet pressure
Residual plot- 
1000 iterations and we can observe that the solution has converged after the 900 iterations.
volume average temperature plot
results
temperature contour cells
velocity counter graph
case2
residual plot
volume average temperature
velocity volume rendering
case3
mesh
residual plot
volume average temperature plot
velocity contour plot
case 4
mesh 4mm
residual plot
volume average temperature plot
velocity conotour plot
on comparing the all 4 cases of the residual plot and the various contour plots we can see the decresing the element size will show a slight change in the temperature rise thus refining the mesh will increase the accuracy and after reaching very small range of mesh almost the acuuracy became constant.
CONCLUSION
flow over the BTMS is performed
heat generation source term was derived based onthe battery specifications
the mesh size was varied and we see that there is a slight improvements in the results and plots