Improving knowledge of tactical rocket motor response under Insensitive Munitions threats IMEMTS PORTLAND - April 2018

Transcription

1 Improving knowledge of tactical rocket motor response under Insensitive Munitions threats IMEMTS PORTLAND - April 2018 Laurent BONHOMME Jean-Michel LARRIEU Florian PECHOUX

2 AGENDA INTRODUCTION IM ADVANCED RESEARCH PROGRAMME APTE FRENCH IM TACTICAL SRM DATABASE NEW GLOBAL IM PROTOCOL FOR TACTICAL SRM FAILURE MODE ANALYSIS TEST PLAN OUTCOME OVERVIEW Test conditions (BI) Alternative stimuli (BI) New architecture (FH) Lesson learned : Test Set-up influence (BI) CONCLUSION Page 2

3 IM ADVANCED RESEARCH PROGRAMME APTE Over last 10 years, French MOD funded the Advanced Research Programme APTE (Tactical Propulsion Improvement). Advanced Research Programme conducted by French Rocket Motor manufacturers ROXEL and ARIANEGROUP. The IM part of the programme was devoted to: Search the best IM compromise for solid rocket motor hardware, Analysis of the standard stimuli representativeness and results interpretation, Evaluate the impact of alternative stimuli or test conditions IM RM Reference Data Base Analysis & study New architectures Analysis & study Stimuli representativity Evaluate alternative stimuli or test conditions Complementary test plan proposal Page 3

4 FRENCH IM TACTICAL SRM DATABASE A database has been populated with more than 220 different test results conducted on Solid Rocket Motors (SRM) and mock-ups in France since the 80 s, and is continuously populated with new results. Characteristics of the tested objects are : Diameter up to 350 mm Metallic, composite and hybrid cases All propellants and igniters types Propellant mass up to 200 kg Tests characteristics, compliance or not with corresponding STANAG test procedure Tests Results with main measurements and hazard classification (reaction level) Database contents : 65 Fast Heating tests (FH) 35 Slow Heating tests (SH) 56 Bullet Impact tests (BI) 17 Fragment Impact tests (FI) 2 Shape charge jet tests (SCJ) 26 Sympathetic Reaction tests (SR) 23 Drop tests Identification of deficiencies and gaps in the technology and knowledge FH 35 SH 56 BI 17 FI 26 SR 2 SCJ 23 Drop I II III IV V NR NC 23 Page 4

5 NEW GLOBAL IM PROTOCOL FOR TACTICAL SRM FAILURE MODE ANALYSIS New protocol is based on AOP39 ones but : dedicated for tactical Solid Rocket Motors (SRM) applicable for all stimuli SRM architecture effects are detailed : SRM materials design and confinement Propellant sensitivity an reactivity Stimuli V COMBUSTION IV PROPULSION AND III - IV EXPLOSION BURST II PARTIAL DETONATION I TOTAL DETONATION RESPONSE CONFINEMENT COMBUSTION DDT MASS REACTION DETONATION ENERGETIC MATERIAL REACTIVITY Ré ti ité COMBUSTION NOT SUSTAINED INITIATION FRICTION XDT PROPELLANT SDT ENERGETIC MATERIAL SENSITIVITY ARCHITECTURE CONFINEMENT PROPELLANT CONFINEMENT CONFINEMENT ARCHITECTURE TRANSFERT FUNCTION THERMAL AGRESSIONS NR MECHANICAL AGGESSIONS NR FH SH BI FI SCJ STANDARD AGGRESSIONS SR Drop Page 5

6 TEST PLAN OUTCOME OVERVIEW : Test conditions (BI) Effect of the temperature on SRM response to BI agression: Three temperature evaluated : Ambiant, -40 C, +70 C Specimen tested : Main characteristics : Composite carbon fibre case (external diameter : 160 mm / Length: 1209 mm) High Burning Rate Propellant (Finocyl shape / about 30 Kg) Page 6

7 TEST PLAN OUTCOME OVERVIEW : Test conditions (BI) BI Tests results : Test conditions : 20 C, Bullet impact velocity = 843 m/s Type IVp (Fragments < 15 m but rear end total displacement > 15 m) Test conditions : -40 C, Bullet impact velocity 838 m/s Type III (Fragments and burning propellant up to 110 m) Test conditions : 70 C, Bullet impact velocity 830 m/s Type IVp (Fragment < 15 m but rear end total displacement > 15 m) Page 7

8 TEST PLAN OUTCOME OVERVIEW : Alternative stimuli (BI) Alternative stimuli : Explosive armor percing 12,7 mm Bullet Specimen tested : Main characteristics : Composite carbon fibre case (external diameter : 160 mm / Length: 1209 mm) High Burning Rate Propellant (Finocyl shape / about 30 Kg) Page 8

9 TEST PLAN OUTCOME OVERVIEW : Alternative stimuli (BI) BI Tests results : Test conditions : 12.7 mm AP Bullet at 843 m/s (Reference) Type IVp (Fragments < 15 m but rear end total displacement > 15 m) Test conditions : 12,7 mm explosive AP Bullet at 863 m/s (Alternative) Type IVp/III (Rear end moved and stopped at 43 m, burning propellant up to 200 m) Page 9

10 TEST PLAN OUTCOME OVERVIEW : New Architecture (FH) New architecture : Optimised confinement release to FCO agression Specimen tested Main characteristics : Composite kevlar/carbon/kevlar fibre case with 180 C resin (external diameter : 165 mm / Length: 1200 mm) Passive venting rear end IM advanced propellant (30 Kg) Page 10

11 TEST PLAN OUTCOME OVERVIEW : New Architecture (FH) FH Test results : Average temperature : 950 C Results : Reaction at 74s Overall deconfinment of the structure at low pressure (composite case and rear end passive venting) No thrust Fragments : Passive venting rear end recovered in the pool Inert fragment < 15m Unburned propellant < 30m Classification : Type V Page 11

12 TEST PLAN OUTCOME OVERVIEW : New Architecture (FH) Application of the global IM protocol for SRM : V IV III - IV II I COMBUSTION PROPULSION EXPLOSION PARTIAL TOTAL AND CONFINEMENT COMBUSTION DDT MASS REACTION DETONATION NO SUSTAINED XDT IGNITION FRICTION PROPELLANT SDT PROPELLANT CONFINEMENT CONFINEMENT THERMAL AGGRESSION NR MECHANICAL AGGRESSION NR FCO Page 12

13 TEST PLAN OUTCOME OVERVIEW : Lesson learned Test set-up influence (BI) Specimen overview : Kevlar over-wrapped grooved steel case (external diameter : 165 mm / Length: 1340 mm) High Burning Rate Propellant (Finocyl shape / about 30 Kg) BI Test Set-up : Page 13

14 TEST PLAN OUTCOME OVERVIEW : Lesson learned Test set-up influence (BI) BI Test results : Test bench rear belt support prevented full venting of the case at low pressure : Classification : Type IV instead of Type V expected due to test bench attachment mean Page 14

15 CONCLUSION Identification of deficiencies and gaps in the technology and knowledge to be evaluated in IM ARP APTE. Simple and unique SRM protocol for all IM aggressions has been established About 40 full scale tests performed by DGA French test centre Knowledge gap filled Interest of new architecture to upgrade the reaction level classification Some architectures have been identified to be used for future applications Alternative stimuli and test conditions impact evaluated Lesson learned : Take care about test set-up influence Page 15

16 Acknowledgements & Questions Members of Any Questions? Page 16