Jarred Alexander Young February 12, 2013. Beam Testing LabView programs successfully upgraded ...

High Energy Plume Impingement on Spacecraft Systems

AFOSR Telecon

Jarred Alexander YoungFebruary 12, 2013

Current Events

Beam Testing LabView programs successfully upgraded Results acquired from differing anode

voltages▪ Shows energy changes across different voltages

Technical Difficulties Filament supply broke down again; two weeks

for shipping and repair Electron conduction problem▪ Recently repaired

New Beam Data

Performed analysis across two settings to see if peak of distribution could be moved Third setting from previous

data (12/20/2012)

Looked at moving filter effects on picoammeter data

Results gathered at similar beam currents

Quantity

Setting 1

Setting 2

Setting 3

Anode Voltage 179 V 190 V 218 V

Discharge

Voltage115 V 126 V 154 V

Accel Grid

Voltage-182 V -182 V -182 V

*Voltages relative to ground

0 50 100 150 200 250 300 3500.00E+00

2.00E+00

4.00E+00

6.00E+00

8.00E+00

1.00E+01

1.20E+01

Ion Energy vs. Collector Voltage ComparisonTest 6 vs. 8

Anode Voltage: 179 VAnode Voltage: 190 V

Collector Voltage (V)

Ion

En

erg

y (

A/V

)

0 50 100 150 200 250 300 3500.00E+00

2.00E+00

4.00E+00

6.00E+00

8.00E+00

1.00E+01

1.20E+01

Ion Energy vs. Collector Voltage ComparisonTest 6 vs. 8

Collector Voltage (V)

Ion

En

erg

y (

A/V

)

0 50 100 150 200 250 300 350

-2.00E-14

-1.50E-14

-1.00E-14

-5.00E-15

0.00E+00

5.00E-15

1.00E-14

1.50E-14

Ion Energy vs. Collector Voltage ComparisonTest 6 vs. 8 vs. 11 (from 12-20-2012) (Different Anode Current from 6 and 8)

Anode Voltage: 179 VAnode Voltage: 190 VAnode Voltage: 218 V

Collector Voltage (V)

Ion E

nerg

y (

A/V

)

0 50 100 150 200 250 300 350

-2.00E-14

-1.50E-14

-1.00E-14

-5.00E-15

0.00E+00

5.00E-15

1.00E-14

1.50E-14

Ion Energy vs. Collector Voltage ComparisonTest 6 vs. 8 vs. 11 (from 12-20-2012) (Different Anode Current from 6 and 8)

Collector Voltage (V)

Ion E

nerg

y (

A/V

)

Beam Data Summary

Data shows that the energy peak is moving as expected As anode voltage increases, peak moves towards the

right of the voltage spectrum

Estimated energy level range: ~100-300 eV

Test #Anode

Current (mA)

Discharge

Current (mA)

Filament Current

(A)

Accel Grid

Current (mA)

Energy Peak (eV)

6 1.68 79.7 4.314 -1.53 175.75

8 1.69 72.5 4.371 -1.62 184.84

11 (from12/2

0).41 14.22 4.051 -.24 236.36 (?)

Coupon Mounting

Designed to mount on the front of the RPA

Allows for: Testing of 3 x 7 mm

material samples▪ Includes silicon

coupons from ISU Monitoring of

energy level during beam exposure

Mount points

Upcoming Tasks

Finish beam energy testing and compile matrix of energy levels

Begin coupon testing at different beam energy levels