1. THE PHYSICAL PROPERTIES OF THE BLAST WAVE PRODUCED BY A STOICHIOMETRIC PROPANE/OXYGEN EXPLOSION MABS22 Bourges, France 2012 by Maura C. Dewey & John M. Dewey Dewey McMillin & Associates Ltd Victoria, BC Canada

2. Operation DISTANT PLAIN 1966 MABS22 Bourges, France 2012

3. Operation DISTANT PLAIN 1966 MABS22 Bourges, France 2012

4. Air Blast Time-of-Arrival Detectors (ABTOADS) Recorder An array of switches was closed by the primary shock, and the signals sent via a single cable to a recorder MABS22 Bourges, France 2012

5. Primary Shock Radius-Time Trajectory Analysis Dewey (2005), J. Phys. D: Appl. Phys., 38, 4245-4251 MABS22 Bourges, France 2012 Propane+oxygen Propane only

6. MABS22 Bourges, France 2012 The Piston Path – Random Choice Method (PP-RCM) G. I. Taylor (1946)

7. MABS22 Bourges, France 2012

8. Smoke Tracer Trajectory Used as the Piston Path MABS22 Bourges, France 2012 MISERS GOLD 2.445 KT ANFO SURFACE BURST

9. Use of an Arbitrary Piston Path MABS22 Bourges, France 2012 Radius Time Observed Shock trajectory Calculated Shock trajectory Arbitrary Piston Path

10. Use of an Arbitrary Piston Path MABS22 Bourges, France 2012 Radius Time Observed Shock trajectory Calculated Shock trajectory Arbitrary Piston Path.

11. Use of an Arbitrary Piston Path MABS22 Bourges, France 2012 Radius Time Observed Shock trajectory Calculated Shock trajectory Arbitrary Piston Path.

12. Comparison of Observed and Calculated Shock Trajectories MABS22 Bourges, France 2012 Propane/Oxygen ABTOAD Data PP-RCM Calculation

13. The PP-RCM Calculated the Physical Properties Throughout the Flow Field MABS22 Bourges, France 2010 Scaled Radius – 2 to 20 m/kg^1/3 at NTP

14. The PP-RCM Calculated the Physical Properties Throughout the Flow Field MABS22 Bourges, France 2010 Scaled Radius – 2 to 20 m/kg^1/3 at NTP Scaled Time – 2 to 50 ms/kg^1/3 at NTP

15. The PP-RCM Calculated the Physical Properties Throughout the Flow Field MABS22 Bourges, France 2010 Scaled Radius – 2 to 20 m/kg^1/3 at NTP Scaled Time – 2 to 50 ms/kg^1/3 at NTP Stored Properties Hydrostatic Overpressure – OP (atm)

16. The PP-RCM Calculated the Physical Properties Throughout the Flow Field MABS22 Bourges, France 2010 Scaled Radius – 2 to 20 m/kg^1/3 at NTP Scaled Time – 2 to 50 ms/kg^1/3 at NTP Stored Properties Hydrostatic Overpressure – OP (atm) Density – ρ (atm)

17. The PP-RCM Calculated the Physical Properties Throughout the Flow Field MABS22 Bourges, France 2010 Scaled Radius – 2 to 20 m/kg^1/3 at NTP Scaled Time – 2 to 50 ms/kg^1/3 at NTP Stored Properties Hydrostatic Overpressure – OP (atm) Density – ρ (atm) Particle Velocity – U/a 0

18. The PP-RCM Calculated the Physical Properties Throughout the Flow Field MABS22 Bourges, France 2010 Scaled Radius – 2 to 20 m/kg^1/3 at NTP Scaled Time – 2 to 50 ms/kg^1/3 at NTP Stored Properties Hydrostatic Overpressure – OP (atm) Density – ρ (atm) Particle Velocity – U/a 0 Calculated Properties Dynamic Pressure, Temperature and Sound Speed

19. Results MABS22 Bourges, France 2012

20. Data Fitted to Modified Friedlander Equation MABS22 Bourges, France 2012

21. Overdensity-Time History at 10 m/kg^1/3 MABS22 Bourges, France 2012

22. Particle Velocity Time History at 20 m/kg^1/3 MABS22 Bourges, France 2012

23. Integration of the Equation over the Positive Duration Provides Quantities such as Impulse MABS22 Bourges, France 2012 Log-log Plot of Impulse versus Scaled Radius

24. Summary MABS22 Bourges, France 2012 All of the physical properties of a stoichiometric Propane/oxygen explosion have been characterised

25. Summary MABS22 Bourges, France 2012 All of the physical properties of a stoichiometric Propane/oxygen explosion have been characterised It has been demonstrated that a hemispherical blast wave can be fully characterised using a simple ABTOAD array