Goal:
Test both designs that have a minimum of 4m^2 solar panel section with roughly realistic proportions. Frontal area should be about 1m^2 to test aerodynamics of both shapes. Test speeds will be 80km/h to simulate competitive racing. Designs are not optimal and should be only be used as a reference.
Catamaran
Study Parameters:
Roughness: 0 Micrometer
Wall Thermal Conditions: Adiabatic Wall
Ambient Conditions:
Results:
Visually good airflow with turbulence slowing the flow down to 14m/s.
At 22.2m/s there was 55.526N of air resistance requiring [55.526(m^2/s)x22.2(m/s)] 1232.68 Watts of energy to maintain it’s speed.
Other Design consideration:
This design has much more surface area for solar panels than we need 6.5m^2 instead of 4m^2. This would allow us to shorten the over all length to reduce weight
Easy(er) to manufacture
More frontal area due to the limitations of needed to fit the driver within one of the horizontal pieces.
Bullet
Study Parameters:
Roughness: 0 Micrometer
Wall Thermal Conditions: Adiabatic Wall
Ambient Conditions:
Results:
More turbulence with this design
At 22.2m/s there was 107.327N of air resistance requiring [100.7(m^2/s)x22.2(m/s)] 2235.66 Watts of energy to maintain it’s speed.
Other Design consideration:
This design is harder to get to 4m^2 for solar panels and not get close to the 5m length restriction.
The would be more easier to design the mechanical systems for since the suspension and steering would be more traditional.
Conclusions:
Based on the rough designs to get an idea of how the two types of vehicles perform, it seems like the catamaran style is more efficient than the bullet style. I think we could get the bullet style closer to the same performance by refining the aero-body (adding a slightly curved solar array, more filets, etc). It is worth noting that designing the mechanical systems would be easier in the bullet style, and there would be much more room for batteries and other components.