Development, evaluation and lifetime prediction of medium and large caliber ammunition

Transcription

1 Development, evaluation and lifetime prediction of medium and large calibre Development, evaluation and lifetime prediction of medium and large caliber Gert Scholtes, 40 th GARM, April 25-28, 2005

2 Overview Ignition propellant Propellant Flight Ignition train Lifetime prediction IM Warhead Surveillance Performance 2 Effectiveness Hit

3 Propellant: Capabilities Modeling & simulation Thermodynamics Processing Internal ballistics Lab-scale production Up to ~ 1 kg (analyses) Small scale production Up to ~ 300 kg Performance testing Closed & vented bombs Test guns Thermal, IM & safety properties 3

4 Propellant: Modeling & simulation Thermodynamics NASA-Lewis, Blake, ICT-code Internal ballistics TIBALCO (TNO Internal BALlistic Code) Processing Rheology Extrusion & shaping processes 4

5 Propellant: Processing 45 mm twin-screw extruder 5

6 Propellant: Test facilities Closed Vessels 43.5 cc / 130 cc LPCV (20 MPa) cc CV ( MPa) 400 cc HPCV (1000 MPa) Erosivity & burning interruption tests 130 cc 20 MPa 500 cc 150 MPa Plasma ignition Instrumented guns.50 gun 29-mm / 50-mm / 78-mm accelerator 6 CV s (25 700cc) Vented HPCV and catch tank

7 Propellant: Examples of R&D projects Propelling charge development Temperature independent propellant Barrel erosion Ageing & lifetime assessment Stick propelling charges for excellent ignition behaviour velocity temperature a% b% 50% a% + 50% no no Poly. (a%) Poly. (b%) Poly. (50% a% + 50% no) Poly. (no) Proven temperature independency 7 Burning properties and mechanical integrity of aged propellants

8 Overview Propellant Flight Ignition train Ignition propellant Lifetime prediction IM Warhead Surveillance Performance 8 Effectiveness Hit

9 MEMs Exploding Foil Initiator (EFI) Intrinsic safe No primary explosives Not sensitive to EM fields Precision timing for initiation (e.g. aimable warheads) Very reliable No need for out-of line of T charge Explosive 9 S C insulation Copper foil Kapton foil

10 MEMs EFI: What you need Proper circuit with COTS components Small high voltage power supply (several kv and ka) Solid state Switching device Appropriate dimensions en properties of: Exploding foil Flyer plate Strip-line Barrel Pressed HNS-IV crystals at the right density Power 4M 3M 2M 1M Performance of an optimised EFI-circuit I (A) P (W) 5.0k 4.5k 4.0k 3.5k 3.0k 2.5k 2.0k 1.5k 1.0k Current (A) n 400.0n 600.0n 800.0n 1.0µ time (s)

11 Ignition train: MEMs EFI 4000 Velocity (m/s) km/s in 80 ns n 40.0n 60.0n 80.0n 100.0n time of flight (s) HNS-IV 11

12 Overview Ignition propellant Propellant Flight Ignition train Lifetime prediction IM Warhead Surveillance Performance 12 Effectiveness Hit

13 Warhead: recrystallisation to obtain the next generation of explosives RS-RDX HNF Insensitive crystals for rocket propellants Insensitive crystals for HE Warheads CL-20 HNS-IV 13 Insensitive crystals for Booster Explosives

14 Warhead: characterisation of explosives Jet snelheid [km/s] RDX SDT RDX BSDT RDX RDX milde reactie I-RDX SDT I-RDX BSDT I-RDX I-RDX Shock initiation testing of small samples velocity [km/s] Shock wave velocity HU Jet diameter [mm] 2.6 km/s 3.0 km/s 3.3 km/s 3.6 km/s 4.1 km/s 5.0 km/s 5.1 km/s 5.6 km/s Shaped charge testing and simulation (PBXN109) distance [mm]

15 Warhead: Understanding the behaviour of explosives and IM 400 Temperature ( C) Temperature ( C) tube_nc exp_nw Texp_2/3 Texp_1/3 Texp_cent Texp_nc Tcont Time (s) tube_nc exp_nw Texp_2/3 Texp_1/3 Texp_cent Texp_nc Tcont Time (s) Cook-off testing and Simulation 15

16 Warhead: Understanding the behaviour of explosives and IM Bullet/Fragment testing and simulation The responses of a confined materials after the impact of a fragment. snelheid (km/s) PBXN109 vlak 22 PBXN109 bol 22 PBXN109 bol18 I-PBXN109 bol Barriere dikte staal (mm)

17 Overview Ignition propellant Propellant Flight Ignition train Lifetime prediction IM Warhead Surveillance Performance 17 Effectiveness Hit

18 Effectiveness: Fragmenting testing 60 m range for HE 76 mm 200 m range for KE 40 mm Bunker for 25 kg TNT 18 Fragment cloud analysis method Rotational symmetry Cylinder with windows Cardboard soft recovery X-ray shadowgraphs Image processing

19 Effectiveness: Fragmenting testing Fragment distribution Spatial Velocity Mass Energy 19

20 Effectiveness: Munition Lethality/Platform Vulnerability Terminal ballistics experiments & simulations 20 Lethality / vulnerability simulations

21 Overview Ignition propellant Propellant Flight Ignition train Lifetime prediction IM Warhead Surveillance Performance 21 Effectiveness Hit

22 Lifetime prediction: How to solve the safety problem? What s the safety? time Accident with propelling charges 22

23 Lifetime prediction: Ageing of missile US AIM-7 Sparrow incidents (1997 & 1999) US MK-58 Mod 2 motor investigation t sec Source: paper P. Huisveld AVT-RTO-089, 2002 Aalborg 23

24 Lifetime prediction: Element toolbox for missiles Missile life firings As-received motor NDT Functional Testing Component Current state + Projected lifetime Computer models Acc. Aged Component characterizing Trend analysis historical data 24

25 Surveillance of gun propellants Range of 5 sample vessels covers the whole range of propellant grains No pre-treatment of grains is necessary 25

26 Surveillance of gun propellants Heat flow Calorimetry (HFC) with full size grains Heat generation in time as function of loading density of vessel Munition like testing KB 7071 fd RH 85 C Heat Generation [mw/kg] gram 10 gram 15 gram 20 gram Time [hours] 26

27 Lifetime production and surveillance: Products Lifetime studies (Toolbox) Surveillance methodology for gun propellants (realistic comparison to situation, including Equipment Tailor made training programme Tailor made munition management system Guarantee and spare parts 27

28 Summary TNO Defence, security and safety is an independent organisation and a strategic partner for the Dutch Ministry of defence We also use our accumulated expertise for foreign governments and for defence related industries. R&D development prototyping pre-production production in service, of munition: TNO has the expertise for Effective and Insensitive Munitions development. But also the expertise for lifetime predictions and surveillance of propellants. Combination of experimental facilities, theoretical knowledge/expertise and model/computer codes makes TNO a qualified partner for your future munitions development. 28