Optical Triggering Results

Coil B

Again we can compare the maximum muzzle speeds obtained open loop triggering and optical triggering. Table 1 shows the resulting speeds for each projectile type.



Open Loop Speed (m/s)

Optical Speed (m/s) Difference (%)
Solid 8.93E+0 8.58E+0 4.08E+0
4 mm Cored 9.35E+0 8.96E+0 4.35E+0
6 mm Cored 9.80E+0 9.36E+0 4.70E+0

Table 1. Comparison of maximum open loop speed and optical speed.


Now we can see that the optical method gives a slightly lower muzzle speed with this coil. The difference is small and indicates that the optical timing setup is close to ideal.

Looking at the operating curves in fig 1 shows that the difference between the supply power and the source power is increasing due to the greater current demand.


Fig 1. Voltage, current and power curves.


Table 2 contains details of the energy and efficiencies for a solid projectile.


Source Energy (mJ) Supply Energy (mJ) Projectile Energy (mJ) Coilgun Efficiency (%) Overall System Efficiency (%)
1.48E+4 1.29E+4 2.87E+2 3.62E+0 3.16E+0

Table 2. Efficiency comparisons for solid projectile.


We can see that all the efficiency ratings for coil B are somewhat better than those for coil A, also, the proportional difference in efficiencies has increased as expected.



Results Coil AResults Coil CTop