test bench for activatable batteries · introduction fraunhofer emi as an engineer for customized...
TRANSCRIPT
© Fraunhofer EMI
60th Annual NDIA
Fuze Conference
May 2017
S. Hess, C. Glößner, S.
Nau, B. Lang, V. Trinler
TEST BENCH FOR ACTIVATABLE BATTERIES
Development of Customized Dynamic Test Systems
Introduction
Fraunhofer EMI as an engineer for customized dynamic test systems
exemplified by a test bench for activatable batteries
Project definition and requirement specification
Concept and technical approach
Realization and first measurements
Summary
AGENDA
3
Introduction
Methods for generating defined shock loads
Nau et al. „Generation and Measurement of Long Duration High-g Accelaration Profiles“,
55th Annual Fuze Conference, Salt Lake City, 2011
D. Hayles, DTRA, Fuze Conference 2010
acce
lera
tio
n [g
]time [ms]
measurement
50 kHz filtered
- Numerical simulation
- Experimental data
Example: 30.000 g, 800 µs
4
Introduction
Methods for generating defined shock loads
Nau et al. „Generation and Measurement of Long Duration High-g Accelaration Profiles“,
55th Annual Fuze Conference, Salt Lake City, 2011
D. Hayles, DTRA, Fuze Conference 2010
required velocity: v0 > 100 m/s
5
Introduction
Pressurized air gun
Working pressure: max. 30 bar, vessel volume: 10 l
Caliber: 45 mm, barrel length: 2 m
Muzzle velocity: up to 175 m/s with m = 130 g
control panel
Inner view to control cabinet
6
Introduction
High-velocity powder gun HVPG
Caliber: 60 mm (Smoothbore)
Barrel length: 6 m
v0,max: 2850 m/s (m = 180 g )
pmax: 650 MPa
Features: use of conventional
propellants
One of the fastest
powder guns in Europe!
2500
2510
2520
2530
2540
2550
2560
175 176 177 178 179 180 181
v16
[m/s
]
test number
v16 = 2527 m/s ± 17 m/s
1600
1800
2000
2200
2400
2600
2800
3000
0 5 10 15 20
ve
loc
ity v
(m
/s)
target distance x (m)
7
Developing dynamic test systems
Test bench for activatable batteries
Expertise in generation of defined acceleration profiles
Defined-Long-Duration (DLD) Shock Test
Expertise in design and construction of dynamic test systems
Several commercialized accelerator systems
Diehl & Eagle Picher needs a:
Flexible laboratory test bench
Various g-loads combined with
Various rotational speeds
Adaptable for different battery types
Withstand thousands of tests per year
© Diehl & Eagle Picher
8
Developing dynamic test systems
Test bench for activatable batteries
Activatable fuze batteries, a short introduction:
Used in fuzes for artillery, mortar and naval gun
ammunition
Long shelf-life
Separation of electrolyte and cell stack during
storage
During gun launch the electrolyte is released by
an activation mechanism and wetted the cell stack
The activation mechanism is driven by the
acceleration
Wetting is mainly driven by the angular velocity
© Diehl & Eagle Picher
© Diehl & Eagle Picher
activatable
fuze battery
9
Test bench for activatable batteries
From requirement specification to realization
Electrical connection during activation
Voltage and current measurement
External electric load
Compliance to European law (CE conformity)
Physical conditions for battery activation:
Linear acceleration for activation:
Amplitude: 1’000 g to 10’000 g
Duration: 0.4 ms to 2 ms(real ammunition, e.g. PzH2000: 12’000 g)
Simultaneously:
variable rotation speed
from 0 rpm up to 18’000 rpm(buzz saw: 7’500 U/min) 0
2.000
4.000
6.000
8.000
10.000
0,4 0,6 0,8 1,0 1,2 1,4 1,6 1,8 2,0
required
Duration [ms]
Acce
lera
tio
n [
g]
© Diehl & Eagle Picher
10
Test bench for activatable batteries
From requirement specification to realization
Approach (developed in cooperation with D&EP):
Generation of g-load for activation by a defined deceleration during impact
Independent generation of rotation (1st) and axial acceleration (2nd)
Use of a rifled barrel is not possible
Keep axial g-load from the ball bearing by a momentum trap
Transmission of the electric signals during the activation process (4-wire)
Battery
initial, soft
acceleration
<< g-load
Moment-
um trap
defined g-load
(compression structure)
shock absorber
rotating barrel electric measurement
11
Test bench for activatable batteries
Experimental and numerical analysis of damping elements
Experimental characterization of different damping elements
Compressive elements
Foams (metal and glass)
Honeycombs
Crashtubes
Damping pads (viscoelastic)
Profile dampers
Numerical design and characterization of damping elements – if appropriate
material model is available
12
Numerical design and characterization of damping elements
13
61 62 63 64 65 66
-500
0
500
1000
1500
2000
Beschle
unig
ung [g]
Zeit [ms]
Messung
Simulation
Characterization of damping elements
g-rec and test-projectile
Measurement
Simulation
Time [ms]
Accele
ration
[g]
14
High-speed slip ring for signal
and power transmission
Test bench for activatable batteriesGalvanic connection between battery and electric load
Sabot with battery
with sliding contacts
insolation tube with
inserted sliding contact
© D
iehl &
Eagle
Pic
her
15
Test bench for activatable batteries
16
Test bench for activatable batteriesRealization and first tests
Rotational speed: 6.000 U/min
Frame rate: 10.000 fps
17
Test bench for activatable batteriesRealization and first tests
1 2 3 4 5 6 7 8 9
-200
0
200
400
600
800
1000
1200
Be
sch
leu
nig
un
g [g
]Zeit [ms]
g-load for activation(recorded with g-rec at same test setup)
Battery voltage vs. time• external measurement with variable load
steps in voltage plot
Time [s]Time [ms]
Vo
lta
ge
[V
]
Acce
lera
tion
[g]
Voltage raw data
18
SummaryDeveloping test benches for defense technology application
Fraunhofer EMIs expertise in:
Generating defined acceleration profiles
Construction of dynamic test benches
Tailor made test bench for activatable batteries
Basic concepts of the test bench
Numeric simulations
First test results
If you need a customized test bench
for your lab, feel free to contact us.
Further Information:Further Information:
Sebastian Hess
Fraunhofer EMI
Am Klingelberg 1
79588 Efringen-Kirchen / Germany
Tel.: +49 76 28 / 90 50 – 631
E-Mail: [email protected]
Thanks for your Attention!
Questions?
Dr. Siegfried Nau
Fraunhofer EMI
Am Klingelberg 1
79588 Efringen-Kirchen / Germany
Tel.: +49 76 28 / 90 50 – 685
E-Mail: [email protected]
This work is funded by DIEHL & EAGLE PICHER GmbH