G. Edward Cort and Jerry H. Fu- Numerical Calculation of Shock-Induced Initiation of Detonation

  • Upload
    ginertg

  • View
    226

  • Download
    0

Embed Size (px)

Citation preview

  • 8/3/2019 G. Edward Cort and Jerry H. Fu- Numerical Calculation of Shock-Induced Initiation of Detonation

    1/19

    . ,\ ..t::~ i(-:- iLA-UR -80-2854

    TITLE: NUMERICALAL CUL AT I ON OF SHOCK- I NDUCED I NI T I AT I ON OF DET ONAT I ONS

    AUTHOR(S): G. Ed wa r d Co r tJ e r r y H. F u

    SUBMllTED TO: J ANNAF I n t e r a g e n c y p r o p u l s i o n Co mmi t t e e , 1 9 8 0 p r o p u l s i o nS y s t e ms Ha z a r d s Me e t i n g , Mo n t e r e y , Ca l i f o r n i a ,o c t o be r 2 7 - 3 1 , 1 9 8 0 .

    Ilv It, [I,lllnlltw (If 1111,.1111(,, !111,1181111

  • 8/3/2019 G. Edward Cort and Jerry H. Fu- Numerical Calculation of Shock-Induced Initiation of Detonation

    2/19

    UNCLASSIFIEDNUMERI CAL CAL CUL AT I ON OFSHOCK- I NDUCED I NI T I AT I ON OF DET ONAT I ONS *

    G. E . Cu r t a n d J . H. M. F uL o s A l a mo s Sc i e n t i f i c L a b o r a t o r yL o s A1 OMDS , Ne ~ Me x i c oABSTRACT

    T h i s p a p e r d e s c r i b e s t h e r e s u l t s o f s o me n u mr i c a l c a l c u l a t i o n s o f t h ei mp a c t o f s t e e l c y l i n d e r s a n d s p h e r e s o n t h e p l a s t i c - b o n d e d h i g h e x p l o s i v ePBX 9 5 0 1 . T h e c a l c u l a t i o n s we r e c a r r i e d o u t b y a r e a c t i v e , mu l t i c o mp o n e n t .t wo - d i ~ n s i o na l , E u l e r ! a n h y d r o d y n a mi c c u n p u t e r c o d e , 2 DE . T h e 2 DE c o mp u -t e r c o d e t s a f i n i t e d i f f e r e n c e c o d e t h a t u s e s t h e d o n o r - a c c e p t o r - c e l lme t h o d t o c u n p u t e mi x ed c e l l f l u x e s .

    T h e mc h a n i s m o f s h o c k i n i t i a t i o n t o d e t n a t i o n i n h e t e r o g e n e o u se x p l o s i v e s i s b e s t d e s c r i b e d a s l o c a l d e c o mp o s i t i o n a t h o t s p u t s t h a t a r ef o r me d b y s h o c k i n t e r a c t i o n s wi t h d e n s i t y d i s c o n t i n u i t i e s . T h e l i b e r a t e dme r g y s t r e n g t h e n s t h e s h o c k s o t h a t a s i t I n t e r a c t s wi t h a d d i t i o n a l i n h o -mo g e n e i t i e s , h o t t e r h o t s p o t s a r e f o r me d , a n d r mr e o f t h e e x p l o s i v e i sd e c o mp o s e d . T h e s h o c k wa v e q r o ws s t r o n g e r u n t i l a d e t o n a t i o n b e g i n s . T h i smc h a n i s m o f i n i t i a t i o n h a s b e e n d e s c r i b e d n u me r i c a l l y b y t h e F c r e s t F i r eb u r n mo d e l , wh i c h g i v e s t h e r a t e o f e x p l o s i v e d e c o mp o s i t i o n a s a f u n c t i o n c fl o c a l p r e s s u r e . T h e p a r a me t e r s i n t h e F o r e s t F i r e b u r n mo d e l h a v e b e e nd e v e l o p e d f r m e x p e r i me n t s wh e r e t h e i n d u c e d s h o c k a p p r o x i ma t e s a p l a ne wa v ~a n d a r e a p p l i e d , i n t h i s c a s e , t o a s i t u a t i o n wh e r e mmt h e i n d u c e d s h o c k i s ad i v e r g e n t wa v e wi t h c u r v a t u r e t h a t d e p e n d s o n t h e s i z e a n d s h a p e o f t h ep r o j e c t i l e .

    T h e c a l c u l a t e d r e s u l t s h a v e b e e n c o mp a r e d wi t h r e s u l t s f r o m e x p e r i -me n t s i n v o l v i n g i n s t r u me n t e d n mc k a n d l i v e h i g h e x p l o s i v e s . wi t h p r o j e c -tiles of varying sizes, shapes, and velocities, We f i n d t h a t t h e r e i s g o o da g r e e me n t b e t we e n t h e c a l c u l a t e d a n d e x p e r i me n t a l d a t a .

    I N T RODUCT I ONA ma j o r p r o b l e m i n t h e h a n d l i n g a n d s t o r a g e o f mu n i t i o n s , a n d o fe x p l o s i v e ma t e r i a l s I n g e n e r a l , i s t h e p o s s i b i l i t y o f t h e p r o p a g a t i o n o fd e t o n a t i o n s f r o m a d a ma g e d wa r h e a d , o r mo t o r i n t o n e a r b y e x p l o r , i v c o l ) j ~ l c t s .Be c a u s e mo d e r n h i g h - s p e c i f i c i mp u l s e s o l i d f u ~ l s a r e COMDOSed ma i n l y o fe x ~ l o s i v e s u b s t a n c e s , c o n c e r n wi t h p r o b l e ms o f s y mp a t h e t i c d e t o n a t i o n h a s

    i n c r e a s e d , T h i s s y mp a t h e t i c d e t o n a t i o n p h e n o me n o n c a n b d c a I J s e d b y t h eb l ~ s t f r c m t h e p r i ma r y e x p l o s i o n o r b y t h e i mp a c t o f d e b r i s f r a g me n t s ,qTh I S mr k wa s s u p p o r t e d b y t h e US De p a r t me n t o f En e r g y , Of f i c e o f Mi l i t a r i yAp p l l c a t l o n s . We g r a t e f u l l y a c k n o wl e d g e t h e a s s i s t a n c e a n d c o n t r i h u t i n n s o fC. L . Ma d ~ r , C. A . F o r e s t , A , L . Bo wma n , J . D, Ke r s h n e r , L , A . Gr i t z o , a n dL . U. Ha n t e l . T h e I n s t r u me n t e d p r o j e c t i l e I mp a c t e x p e r i me n t s we r e p e r f o r n r db y G. A . Ca r l s o n , T , R. K i n g , R, J . De Wi t t , J . A . Sa n c h e z , a n dK , C. Pe c l e r s o n : t h e u n l n s t r u me n t e d e x p e r i ~ n t s we r e p e r f o r me d b yJ . A . Sa n c h e z a n d K . C. Pe d e r s o n .Approved for public r e l e a s e ; d i s t r i b u t i o n u n l i mi t ~ d .

    .- IIIW,IAMIR . UNCLASSIFIED,, ,,,., . . .,., ,. ,.,.. ,., .,. .,,.., ,,. ,.,

  • 8/3/2019 G. Edward Cort and Jerry H. Fu- Numerical Calculation of Shock-Induced Initiation of Detonation

    3/19

    UNCLASSIFIEDT h i s s t u d y c o n c e n t r a t e s o n i mp a c t b y s i mu ? a t e d s t e e l d e b r i s f r a g me n t s o nF 1 3 X 9 5 0 1 , a mi x t u r e o f 9 5 % Hh i X - 2 , 2 , 5 n i t r o p l a s t i c i z e r , a n d 2 . 5 ; .E s t a n e b ywe i g h t . T h e a p p r o a c h u s e d h e r e c o u l d b e a p p l i e d wi t h mo r e t y p i c a l r o c k e tp r o p e l l a n t s . t o d e t e r mi n e c r i t i c a l d e b r i s p a r t i c l e s i z e s a n d v e l o c i t i e st h a t v n u l d n e t c a u s e a d e t o n a t i o n .

    T h e s h o c k i n i t i a t i o n o f a d e t o n a t i o n r e f e r s t o a p r o c e s s i n wh i c h as h o c k wa v e i n d u c e d i n a n e x p l o s i v e c h a r g e d e v e l o p s i n t o a p r o p a g a t i n g d e t o -n a t i o n wa v e . ! n ma n y e x p e r i me n t a l s t u d i e s , t h e i n d u c e d s h o c k i s g e n e r a t e db y a p l a r e - wa v e l e n s o r b y a f l y i n g p l a t e wh o s e c h a r a c t e r i s t i c l e n g t h i sl a r g e r t h a n o r i s c o mp a r a b l e t o t h a t o f t h e e x p l o s i v e s a mp l e . I n t h o s es t u d i e s , t h e a s s u mp t i o n t h a t t h e i n d u c e d shock is a p l a n e wa v e i s a r e a s o n -a b l e a p p r o x i ma t i o n b e f o r e t h e a r r i v a l o f t h e ml o a d i c g r a r e f a c t i o n wa v e s .T h e p l a n e - wa v e a p p r o x i ma t i o n h a s b e e n u s e d i n t h e s e n s i t i v i t y s t u d i e s o fma n y e x p l o s i v e s . T h e we l l - k n o wn Po p p l o t s f o r a v a r i e t y o f e x p l o s i v e s a r et h e r e s u l t o f t h o s e s t u d i e s . T h e Po p p l o t o f a n e x p l o s i v e i s a s e n s i t i v i t yi n d i c a t o r t h a t e x p r e s s e s t h e d i s t a n c e o f r u n t o d e t o n a t i o n a s a f u n c t i o n o ft h e i n i t i a l p r e s s u r e .

    Wh e n a s ma l l p r o j e c t i l e s t r i k e s a h i g h e x p l o s i v e ( HE ) s a mp l e , t h ep r o p a g a t i n g s h o c k wa v e ma y d e c a y a n d d i e . f a i l i n g t o i n i t i a t e a d e t o n a t i o n ,o r i t ma y b e a mp l i f i e d a n d i n i t i a t e a d e t o n a t i o n - i n t h e e x p l o s i v e . T h ed e c a y o f t h e wa v e i s c a u s e d b y r a r e f a c t i o n wa v e s f r o m i n t e r f a c e s a n d b yg e o me t r i c - d l v e r g e r l c e e f f e c t : b o t h we a k e n t h e s h o c k . On t h e o t h e r h a n d ,s h o c k i n t e r a c t s wi t h d u n s i t y d i s c o n t i n u i t i e s t o c r e a t e l o c a ~ ~ ~ p ~ ~ ~ ~ ~ ~ ~ , 2 T h e e n e r g y r e l e a s e d f r o m t k t e s h o c k - i n d u c e d d e c o mp o s i t i o no f t h e e x p l o s i v e a t h o t s p o t s s t r e n g t h e n s t h e s h o c k . I f t h e s t r e n g t h e np r o c e s s p : - e v a i l s , a d e t o n a t i o n wi l l r e s u l t . T h u s , t h e s h o c k i n i t i a t i o n

    t h et h e

    n gi na n e x p l o s i v e s t r u c k b y a p r o j e c t i l e d e p e n d s o n t h e t y p e a n d c o n f i g u r a t i o no f t h e t a r g e t e x p l o s i v e a n d t h e ma t e r i a l , v e l o c i t y , a n d s h a p e o f t h e i n c i -d e n t p r o j e c t i l e .EXPER I MENTS

    T h e n u me r i c a l s t u d y a n d a c c o mp a n y i n g e x p e r i me n t s i n v o l v e d a s i n g l et y p e o f t e s t . T h e p r o j e c t i l e s we r e f i r e d f r o m a g a s u n a t a s ma l l b l o c k!o f PBX 9 5 0 1 o r 9 0 0 - 1 0 mo c k ( 1 . 8 6 7 g / c m3 ( 1 1 6 . 7 l b m/ f t ) d e n s i t y ) e x p l o -s i v e . T h e 9 0 0 - 1 0 a n d s o me o f t h e PBX 9 5 0 1 b l o c k s we r e i n s t r u me n t e d wi t hc a r b o n a n d Ma n g a n i n g a u g e s t o n wa s u r e p r e s s u r e a n d Co n s t a n t a n g a u g e s t ome a s u r e s t r a i n s . T h e g a u g e s we r e l o c a t , e c lo r l - a x i s a t 1 7 mr r ( 0 . 6 7 i n , ) a n d3 4 nun ( 1 , 3 4 i n . ) f r o m t h e i mp a c t s u r f a c e a n d 1 0 r I wT I( 0 . 3 9 i n . ) o f f - a x i s a t1 7 mm ( 0 . 6 7 i n . ) f r o m t h e i mp a c t s u r f a c e . A s u mn a r y o f t h e r e s l l l t s t h a ta r e u s e d a s a b a s i s f o r c o mp a r i s o n wi t h t h e n u me r i c a l f . a l r ( l l a l i n n s i s q i v p ni n T a b l eF o r ~

    ( 2 7 7 2 f t ,( 0 . 6 7 i nGPa ( ? . 0PBX 9 50 1

    1.7 . 6 2 n m ( 0 , 3 0 i n . ) - d i a m s t e e l c y l i n d ~ r s i mp a c t i n g a t F M5 m/ sS) on 9 0 0 - 1 0 . t h e p e a k s h o c k p r e s s u r e s me a s u r e d a t 1 7 mm) a n d 3 4 n wn ( ] , 3 4 i n . ) o n - a x i s we r e 0 . 2 q C. 0 3 a n d O. Ob * 0 . 0 1 5* 0 . 3 a n d 0 , 6 0 q 0 , 1 5 k b a r ) , r e s p e c t i v e l y . F o r t h e s a me i mp , l c t o nt h e a v c r a q e p r e s s u r e s we r e a b o u t a f a c t o r o f 8 h i a h e r h e c a u s c o ft h e l o w- o r d e r r e a c t i o n s i n t h e } I E, b u t a f u l l d e t o n a t i o n d i j n o t . o r c l l r .T h e u n i n s t r u me n t e d PBX 9 5 0 1 d e t o n a t e d o n I mp a c t a t 8 7 3 m/ s ( 2 R6 4 f t / s ) wi t ht h e s a me p r o j e c t i l e . A c y l i n d r i c a l p r o j e c t i l e a l mo s t h a l f t h ~ r t i a m~ t r r

    UN CL A S S I F I E D

  • 8/3/2019 G. Edward Cort and Jerry H. Fu- Numerical Calculation of Shock-Induced Initiation of Detonation

    4/19

    UNCLASSIFIEDT ABL E I

    S UMMA RY OF E XP ERI ME NT AL RE SUL T SI . I n s t r u me n t e d T a r g e t s , PBX 9 5 0 1 a n d 9 0 0 - 1 0 ( - 1 m Ra n g e )7 . 6 2 n wn d i a m x 1 5 . 2 4 n v n l o n g ( 0 . 3 0 i n . d i a m x 0 . 6 ! ) i n . l o n g ) s t e e lc y l i n d e r s a t 8 4 5 q 10m/s (2772 * 33 f t / s ) . a

    Pe a k Sh o c k P r e s s u r e ( GPa ) hSj:t I?19Q On Ax i s 1 0 mm ( 0 . 3 9 i n . ) Of f A x i s1 7 mm (0.67 i n . ) 3 4 mm ( 1 . 3 4 i n . ) _ 1 7 n n n ( 0 . 6 7 i n . )1.2.3.4.5.6.AVGAVG

    9 0 0 - 1 09 0 0 - 1 09 0 0 - 1 09 0 0 - 1 0PBX 9 5 0 1PBX 9 50 19 0 0 - 1 0P 9 X 9 5 0 1

    0 . 2 3 00 . 2 CX )0 . 1 7 00 . 1 4 01 . 2 5 01 . 6 7 00 , 2 0 q 0 . 0 31 . 5 3 0 * 0 . 2 5

    0 . 0 5 0 . 1 6 00 . 0 7 0 . 1 : 00 : 0 70 . 4 1 0 . ; 0 01 . 5 5 00 . 0 6 0 q 0 . 0 1 5 0 1 4 5 * 0 . 0 20 . 4 1 G 1 . ? 2 0 q 0 . 3 5 0

    1 1 . Un i n s t r u me n t e d T a r g e t s , PEX 9 5 0 1 ( 1 2 m Ra n g e )Shot S t e e l P r o j e c t i l eNo . S i z e , mn ( i n . ) Sh a p e Ve l o c i t y , m; s ( f t / r ) Re s u l t c .

    1 - 7 6 . 3 5 ( 0 . 2 5 ) d i a m s p h u r - e 1 2 3 8 t o 2 5 0 6 No g ~~ 4 0 6 2 t o 8 2 2 2 )8 7 . 6 2 ( 0 . 3 0 ) d i r + c y l i n d e r 8 7 3 ( 2 8 6 4 ) Gox 1 5 . 2 ( 0 , 6 0 ) l u n g9 3 , 3 5 ( 0 . 1 3 ) d i a m c y l i n d e r 2 2 7 5 ( 7 46 d ) Gox 6 . 7 1 (0,?6) l o n g10 3 . 3 5 ( 0 . 1 3 ) d i a m c y l i n d e r 2 0 9 3 ( 6 8 6 7 ) No g oX 6 , 7 1 ( 0 . 2 6 ) l c n g1 1 3 . 35 ( 0 . 13 ) d i a m c y l i n d e r 2 1 7 8 ( 7 1 4 6 ) Gox 6 . 7 1 ( C, 2 6 ) l o n g

    1 2 - 1 5 7 . 9 4 ( 0 . 3 1 ) d i a m s p h c . r e 1 7 0 0 t o 1 8 5 0 No CJO( 5 5 7 7 t o 6 0 : 0 )11 p r o j e c t i l e s s t r ~ c k t h e PBX 9 5 0 ! s u r f a c e a t 0 o b l i q u i t y , wi t h i n 5 mm( 0 . 2 0 i n . ) o f c e n t e r l i n e .b l GPa ~ l o k b a r .

    c Go _ d e t o n a t i o n .

    UNCLASSIFIED

  • 8/3/2019 G. Edward Cort and Jerry H. Fu- Numerical Calculation of Shock-Induced Initiation of Detonation

    5/19

    UNCLASSIFIEDcaused a detonation at 2178 m/ s ( 7 1 4 6 f t / s ) , b u t n o t a t 2093 mls(6867 f t / s ) .

    No detonations we r e o b s e r v e d wi t h 7 . 9 4 n m- d i a m ( 0 . 3 1 i n . ) s p h e r i c a lp r o j e c t i l e s a t v e l o c i t i e s t o 1 . 8 5 k m/ s (6070 f t / s ) . Sp h e r i c a l p r o j e c t i l e s6 . 3 5 m ( 0 . 2 5 i n . ) i n d i a m d i d n o t c a u s e d e t o n a t i o n s a t v e l o c i t i e s up to2 . 5 0 6 k m/ s ( 8 2 2 2 f t / s ) .MODEL

    T h e c o mp u t a t i o n o f s y mp a t h e t i c d e t o n a t i o n f r o m p r o j e c t i l e i mp a c t wa sp e r f o r n wd wi t h t h e t w - d i me n s i o n a l E u l e r i a n r e a c t i v e h y d r o d y n a mi c c o d e ,2 DE , 2 ~ 3 u s i n g t h e F o r e s t F i r e b u r n r a t e . 1 ~ 2 T h e e q u a t i o n - o f - s t a t e d a t au s e d i n t h e s e c a l c u l a t i o n s a r e g i v e n i n Ap p e n d i x A~ T h e F o r e s t F i r e b u r n ,r a t e p a r a mt e r s a n d P o p p l o t d a t a a r e g i v e n i n Ap p e n d i x B . T h e P o p p l o t sf o r PBX 9 5 0 1 a n d PBX 9 4 0 4 * a r e g i v e n i n F i g . 1 . T h e d e n s i t y o f t h ePBX 9 5 0 1 u s e d i n t h e s e e x p e r i me n t s a n d c o mp u t a t i o n s wa s 1 . 8 3 3 g / c m3( 1 1 4 ) 6 l b m/ f t 3 ) . PBX 9 5 0 1 i s s l i g h t l y l e s s s e n s i t i v e t h a n PBX 9 4 0 4 .T h e s c a t t e r i n t h e e x p e r i me n t a l d a t a f o r PBX 9 5 0 1 g i v e s a n i n d i c a t i o n o ft h e r e l a t i v e e r r o r i n o u r c a l c u l a t e d r e s u l t s . T h e p a r t i a l l y r e ~ c t e dHu g o n i o t s a r e g i v e n i n F i g . 2 f o r 9 0 0 - 1 0 , PBX 9 5 0 1 , a n d PBX 9 4 0 4 .

    T h e c o n f i g u r a t i o n o f t h e e x p l o s i v e t a r g e t i n t h e c o mp u t e r mo d e l i sc y l i n d r i c a l wi t h t h e c e n t e r l i n e s o f t h e p r o j e c t i l e a n d t a r g e t c o i n c i d e n t( F i g . 3 ) . T y p i c a l me s h d i me n s i o n s a n d n u mb e r s o f c o mp u t a t i o n a l c e l l s a r eg i v e n i n t h e R a n d Z d i r e c t i o n s .A n i mp o r t a n t p a r a me t e r i n n u mr i c a l mo d e l i n g o f s h o c k wa v e s i s t h ea r t i f i c i a l v i s c o s i t y u s e d i n f i n i t e - d i f f e r e n c e s o l u t i o n s t o s me a r o u t t h es h o c k . W t h o u t a r t i f i c i a l v i s c o s i t y . t h e s t e p c h a n g e s i l l p r e s s u r e a n d t e m-p e r a t u r e a c r o s s t h e s h o c k c a n o c c u r wi t h i n a s i n g l e me ~ n c e l l a n d ma k e t h e

    n u me r i c a l s o l u t i o n u n s t a b l e . T h e r e i s n o a pr io r i mt h o d o f d e t e r mi n i n gt h e b e s t v a l u e o f t h e a r t i f i c i a l v i s c o s i t y f o r al-y g i v e n p r o b l e m, a l t h o u g ht h e s h o c k mu s t b e s n a r e d across a f e w ms h c e l l s f o r s t a b i l i t y . l f t h ea r t i f i c i a l v i s c o s i t y i s t o o l a r g e , t h e s h o c k p r e s s u r e wi l l b e r ~ d u c e d .T h i s wo u l d b e p a r t i c u l a r l y s e r i o u s i n t h e p r e s e n t s t u d y b e c a u s e t h e F o r e s tF i r e b u r n r a t e wo u l d a l s o b e a f f e c t e d b y t h e i n c o r r e c t p r e s s u r e . T h en u me r i c a l n md e l wa s c a l i b r a t e d b y e n s u r i n g t h a t t h e a r t i f i c i a l v i s c o s i t ywa s s ma l l e n o u g h t h a t t h e n u me r i c a l mo d e l p r e d i c t e d t h e me a s u r e d p r e s s u r e si n t h e e x p e r i me n t s .RE SI J L T S

    9 0 0 - 1 0F o r t h e c y l i n d e r i mp a c t c o r r e s p o n d i n g t o t h e e x p e r i me n t sT a b l e 1 1 g i v e s t h e c a l c u l a t e d p e a k s h o c k p r e s s u r e s c o r r e s p o n dme a s u r e me n t l o c a t i o n s .

    * Co mp o s i t i o n O1 PBX 9 4 0 4 i s 9 4 HMX , 3 r l t t r o c ~ l l u l o s e , a n d 3c h l o r o e t h y l p h o s p h a t e .

    c o n d i t i o n s .n g t o t h e

    t r i s - O-

    UNCLASSIFIED

  • 8/3/2019 G. Edward Cort and Jerry H. Fu- Numerical Calculation of Shock-Induced Initiation of Detonation

    6/19

    UNCLASSIFIEDT ABL E 1 1

    PEAK SHOCK PRESSURE I N 9 0 0 - 1 0S t r u c k b y 7 . 6 2 mm ( 0 . 3 0 i n . ) d i a m Cy l i n d e ra t 8 4 5 ml s ( 2 7 7 2 f t l s ) .

    L o c a t i o n P e a k P r e s s u r e , GPa aY e a s u x Ca l c u l a t e d, On a x i s , Z = 1 7 mm ( 0 . 6 7 i n . ) 0 . 2 0 0 * 0 . 0 3 0 , 2 3 5Of f a x i s , Z = 1 7 mm ( 0 . 6 7 i n . ) 0 . 1 4 5 * 0 . 0 2 0 . 2 0 5al GP a = 1 0 k h a r .

    A s e r i e s o f p r e s s l J r e p r o f i l e s ( F i g . 4 ) t a k e n a l o n g t h e a x i s a t v a r i o u st i me s a f t e r i mp a c t , s h o ws t h a t t h e l e a d i ; t g e d g e o f t h e s h o c k wa v e i s f a i r l ys h a r p a n d e x t e n d s a c r o s s s e v e r a l me s h c e l l s . T h e a r t i f i c i a l v i s c o s i t y u s e df o r t h i s c a s e i s 0 . 2 5 . F i g u r e 5 s i l o ws i s o b a r s a t a b o u t 2 u s a f t e r i mp a c t .i n d i c a t i n g t h e c u r v a t u r e c a u s e d b y ~ z we f a c t i o n s a n d d i v e r g e n c e .PBX 9 5 0 1

    T h e s a me c a l c u l a t i o n a l mo d e l wa s u s e d f o ? t h e P 2 X 9 5 0 1 e x c e p t f o r t h ep r o p e r t i e s . T h e i mp a c t v e l o c i t y wa s a g a i n 8 4 5 m/ s 2 7 7 2 f t / s ) . T a b l e I I Ig i v e s the c o mp a r i s o n b e t w e e n t h e a v e r a g e e x p e r i n t e n : . a l a n d c a l c u l a t e d p e a ks h o c k p r e s s l l r e s . A l t h o u q h c o n s i d e r a b l e d e c o mp o s i t i o n o f t h e HE t o o k p l a c e .t h e r e wa s n o d e t o n a t i o n i n e i t h e r t n e e x p e r i me n t o r t h e c a l c u l a t i o n .F i g u r e 6 S h Oh S t h e s h o c k p r e s s u r e a n d t h e u n b u r n e d ma s s f r a c t i o n v e r s u sd i s t a n c e ( c e l l n u mb e r ) a l o n g t h e Z a x i s . T h e n c r e a s e i n p e a k p r e s s u r eo v e r t h a t o b s e r v e d wi t h 9 0 0 - 1 0 i s a c c . ~ s e q u e n c e o f t h e e n e r g y i - e l e a s e d b yc h e mi c a l d e c o mp o s i t i o n o f t h e PBX 9 5 0 1 . T h e c u r v a t u r e i n t h e s h o c k wave ise s s e n t i a l l y i d e n t i c a l t o t h a t o b s e r v e d W. t h 9 0 0 - 1 0 ( F i g . 7 ) .T ABL E 1 ; 1

    PEAK SHOCK PRESSURE I N P6 X 9 5 0 1S t r u c k L y 7 . 6 ? m ( 0 . 3 ~ i n . ) - d i a m c y l i n d e ra t E ! 4 5 ml s ( 2 7 7 2 f t l s ) .P e a k P r e s s u r e . GPa a

    L o c a t i o n Me a s u ~ a ) c u l a t e d

    On a x i s . 7 = 1 7 mm ( 0 . 6 7 i n . ) 1 . 5 3 0 * 0 . ? 5 1 . 4 s 0o f f a x i s . Z = i 7 mm ( 0 . 6 7 i n . ) 1 0 2 2 0 * 9 . 3 5 0 1 . 1 6 0

    T h e c ~ l c u l a t i t i l l wa s t h e n r e p e d t e d wi t h i d e n t i c a l p a r a mt e r s e x c e p tt h a t t h e c y l i n d e r v e l o c i t y wa s i n c r ea s e d t o 8 7 3 m/ s ( 78 6 4 f t / s ) . A f u l ld e t o n , l t i o n o c c u r r e d a f t e r a r u n ( I f 7 . 1 4 mm ( 0 . 2 8 i n . ) . B a s e d o n a n i n i t i a lp r e s s l r e o f 5 . 5 GPa ( 5 5 k b a r ) f r o m ma t c h e d Hu g o n i o t s f o r s t e e l a n du n r e a ( t e d PBX 9 5 0 1 , t h e Do p p l o t i n d i c a t e s a r u n t o d e t o n a t i o n o f 4 . 5 ? mm

    UNCLASSIFIED

  • 8/3/2019 G. Edward Cort and Jerry H. Fu- Numerical Calculation of Shock-Induced Initiation of Detonation

    7/19

    UNCLASSIFIED(0.18 i n . ) , T h e i n c r e a s e d d i s t a n c e t o d e t o n a t i o n c a n b e a t t r i b u t e d t o t h ed e c a y i n s h o c k p r e s s u r e wi t h d i v e r g e n c e . F i g u r e 8 s h o ws i s o b a r s a n d c o n -t o u r s o f c o n s t a n t ma s s f r a c t i o n f o r t i me s j u s t b e f o r e a n d j u s t . a f t e r t h es t a r t o f d e t o n a t i o n , 5 0 c o mp u t a t i o n a l c y c l e s , o r l e s s t h a n 0 . 5 u s a p a r t .T h e c o r r e s p o n d i n g p r e s s u r e p r o f i l e s a n d ma s s f r a c t i o n s v e r s u s d i s t a n c ea l o n g t h e c e n t e r l i n e a r e s h o wn I n F i g . 9 . T h e s h o c k p r e z s u r e i s i n c r e a s i n gwi t h t i me a s t h e d e t o n a t i o n b u i l d s u p b e h i n d i t . E v e n t u a l l y , a s t e a d yd e t o n a t i o n wa v e wi l l b e r e a c h e d wi t h p e a k p r e s s u r e e q u a l t o 3 3 . 5 GPa( 3 3 5 k b a r ) , s l i g h t l y l e s s t h a n t h a t o f t h e Ch a p ma n - J o u g u e t j o i n t .

    Cy l i n d e r , 3 . 3 5 mm ( 0 . 1 3 i n . ) - d i a mi . ! l J c hi g h e r v e l o c i t i e s we r e r e q u i r e d t o c a u s e a d e t o n a t i o n i n t h ee x p e r i me n t s wi t h t h e s ma l l e r c y l i n d e r . T h e s ame c omp u t a t i o r l a l mo d e l wa su s e d . e x c e p t t h a t t h e n w? s h s i z e wa s r e d u c e d t o h e l p r e s o l v e p a r a mt e r s o nt h e s ma l l e r s c a l e . T h e b e h a v i o - o f t f i e e x p l o s t v e i s q u i t e d i f f e r e n t t h a nd e s c r i b e d p r e v i o u s l y f o r t h e l a r g e r c y l i n d e r . F i g u r e 1 0 s h o ws t h e p e ~ kp r e s s u r e i n t h e e x p l o s i v e p l o t t e d a s a f u n c t i o n J i t i me a f t e r t h e i m~ a c tf o r t h r e e d i f f e r e n t s e t s o f c o n d i t i o n s :1. Impact at 2.093 k m/ s ( 6 8 6 7 f t / s ) wi t h t h e c h e r i c a l r e ~ c t i o r , i nt h e e x p l o s i v e t u r n e d o f f .2 . I mp a c t a t 2 . 0 g 3 k m/ s ( 6 9 6 7 f t / s ~ wi t h t h e F o r e s t F i r e ktiJrr, mn d e ?( r e a c t i o n t u r n e d o n ) .3 . I mp a c t a t 2 . 1 7 8 k m/ s ! 7 1 4 6 f t / s ) w i t h t h ~ F o r e s t F i r e b ~ - n mo d e l .I n t h e f i r s t c a s e , t h e p e a k p r e s s u r e d o e s n o t e q l ~ a l t ~ l e 18.4 GP a(184 kbar) predicted f r o m m~ t c h e d Hu g o r l i o t s f o r t h e n o n r e a c t e r l HE a n i !s t e e l . I n t h e s e c o n d c a s e , t h e p r e s s u r e r i s e s i n a b o u t 0 . 3 Us t o a h wt2 8 GPa ( 2 8 0 k b a r ) b e c a u s e o f t h e r e a c t i o n , b u t a g a i n f a l l s o f f . S o me o ft h e c o mp u t a t i o n a l c e l l s n e a r t h e c e n t e r l i n e a n d t h e i mp a c t i n t e r f a c e a r ec omp l e t e l y r e a c t e d , a c o n c ! i t i o n t h a t o r d i n a r i l y ( i n o n e - d i m~ n s i o na l c o mp u -t a t i o n s o r ; n t h o s e j u s t d e s c r i b e d f o r t h e l a r q e r c y l i n d e r ) wo u l d p r o p a g a t ei n t o ~ h i g h - o r d e r d e t o n a t i o n , I n t h i s c a s e . t h e p r o j e c t i l e i s s ma l l ~ n o u q ~ ~t h a t s i d e ~ a r e f a c t i o n s q u i c k l y r e d u c ~ t h e p e a k p r e s s u r e a n d t h e e x p l o s i v ed ~ e s n o t d e t o n a t e , i n a g r e e me n t wi t h e x p e r i me n t a l o b s e r v a t i o n s . As ama t t e r o f i n t e r e s t , t h e f a i l u r e d i a me t e r f o r PEX 9 4 0 4 i s 1 , ? 0 q 0 . ? n w

    ( 0 . 0 4 7 q 0 . 0 0 8 i n . ) , s h o u t 3 5 Cf t h e p r o j e c t i l e s r i i a me t ~ r . T I I p f a i l ~ J ) - ed i a me t e r f o r PBX 9 5 0 1 h a s n o t b e e n d e t e r mi n e d , h u t s h o u l d h e a p p - o y i ma t v ! yt h e s ame . I n t h e t h i r d c a s e . t n e p e a k p r e s s u r e r i s e s t o a b o u t 2 8 GPa( 28 0 k b a r ) i n t h e f i r s t 0 . 3 v s a n d f a l l s t o a b o u t 1 4 GPa ( 1 4 0 k h a r ) a h n u t1 . 0 u s a f t e r t h a t . Ho we v e r , b e c a u s e t h e e n e r g , v r e l e a s e d i n t h ~ ; h ~mi r a lr e a c t i o n i s e n o u g h t o a v e r c o me t h e e f f e c t o f t h e s i r h = r a r e f a c t i r ) n c , t h rp e a k p r e s s u r e i n c r e a s e s a g a i n a n d a f u l l d e t o n a t i o n r e s l l l t . s ,

    T h e i s o b a r s a n d c o n t o u r s o f c o n s t a n t ma s s f r a c t i n n f n r t h ~ I a l t e r t woc a s e s a r e c o mp a r e d i n F i g . : 1 .

    UNCLASSIFIED

  • 8/3/2019 G. Edward Cort and Jerry H. Fu- Numerical Calculation of Shock-Induced Initiation of Detonation

    8/19

    UNCLASSIFIEDSp h e r e , 6 . 3 5 I ! WI I0 . 2 5 i n . ) - d i a mT h e i mp a c t o f t h e s t e e l s p h e r e wi t h t h e PBX 9 5 0 1 wa s c a l c u l a t e d f o r

    o n e v e l o c i t y , 1 8 5 2 m/ s ( 6 0 7 7 f t / s ) . Re c a l l t h a t t h e e x p e r i me n t s d e t e r mi n e dt h a t n o d e t o n a t i o n o c c u r r e d f o r s e v e n t e s t s wi t h i mp a c t v e l o c i t i e s r a n g i n gf r o m 1 . 2 3 8 t o 2 . 5 0 6 k m/ s ( 40 6 2 t o 6 7 4 5 f t / s ) . T h e i s o b a r s a t 0 . 2 0 US a n d1 . 5 8 US a f t e r i mp a c t a r e s h o wn i n F i g . 1 2 . T h e e f f e c t o f r a r e f a c t i o n s c a nb e s ~ n a t t h e s p h e r e - HE i n t e r f a c e . T h e p e a k p r e s s u r e r e a c h e d i n t h i s c a s ei s o n l y 11 GPa ( 0 . 1 1 Mb a r ) v e r s u s 1 5 . 4 GPa ( 0 . 1 5 4 Mb a r ) t h a t i s p r e d i c t e df r o m ma t c he d Hu g o n i c t s f o r n o n r e a c t i n g e x p l o s i v e a n d s t e e l .CONCL US I ONS

    T h e s h o c k - i n d u c e d d e t o n a t i o n o f s ma l l s a mp l e s o f PBX 9 5 0 1 b y t h ei mp a c t o f p r o j e c t i l e s o f d i f f e r e n t s h a p e s a n d s i z e s h a s b e e n mo d e l e d s u c -c e s s f u l l y . T h e r e s u l t s o f t h e c a l c u l a t i o n s a r e i n g o o ~ a g r e e me n t wi t he x p e r i me n t a l o b s e r v a t i o n s . We c a n p r e d i c t o t h e r r e s u l t s f r o m c o n s i d e r a -t i o n s o f p r o j e c t i l e v e l o c i t y , s i z e , s h a p e , a n d e x p l o s i v e p r o p e r t i e s .T h e c u r v a t u r e o f t h e i mp a c t - i n d u c e d s h o c k wa v e c a u ~ e d b y s i d e r a r e f a c -t , i o n s a n d g e o me t r i c d i v e r g e n c e i s t h e ma j o r d i f f e r e n c e b e t we e n t h i s c l a s so f s h o c k - i n d u c e d d e t o n a t i o n a n d t h a t c a u s e d b y a p l a n e - wa v e l e n s o r f l y e rp l a t e . T h e s e e f f e c t s c a n n o t b e s c a l e d e a s i l y b e c a u s e o f n o n l i n e a r i n t e r a c -t i o n s .

    APPENDI X AEQUAT I ON OF ST AT E

    T h e HOM e q u a t i o n o f s t a t e i s u s e d t o s ? l v e f o r p r e s s u r e P a n dt e mp e r a t u r e T i n a c e l l , wi t h s p e c i f i c v o l u me V a n d s p e c i f i c i n t e r n a le n e r g y I a s i n p u t . T h e s h o c k v e l o c i t y Us a n d t h e p a r t i c l e v e l o c i t y Upa r e r e l a t e d b y

    l+ = c + sup.T h e e q u a t i o n s f o r a s o l i d a r e

    PH = C?(VO - v)/[/o - S(vo v)]?X= i n v

    I H K ( 1 / ? ) p H( V ~ - V )

    T = ( I - I H) ( 2 3 8 9 0 ) / Cv r HT h ~ e q u a t i o n s f o r a g a s a , e

    UNCLASSIFIED

  • 8/3/2019 G. Edward Cort and Jerry H. Fu- Numerical Calculation of Shock-Induced Initiation of Detonation

    9/19

    UNCLASSIFIEDY = in P iY = A+ BX+ c X2 + DX3 + EX4

    ~ n I i = K+ L y +My 2 +Ny 3 +o y 4I i = I i - Z

    $ n T i = Q+ RX SX2 + T x 3 + UX4- 1 / B = R + 2 SX + 3 T X2 4 UX3

    P = [1/(BV)] (1 - Ii) + PiT = (I - 11 ) (23 E!90)f~ + Tj

    T h e s o l u t i o n f o r a c e l l w i t h mo r e t h a n o n e c o mp o n ~ n t i s b a s e d o nc o mb i n a t i o n - o f t h e s e e q u a t i o n s . 2 ~ 3

    T h e e q u a t i o n - o f - s t a t e p a r a me t e r s u s e d i n t h i s s t u d y a r e t a b u l a t e d i nT a b l e A - I . T h e u n i t s a r e v o l u me ( c mS / g ) , e n e r g y ( Mb a - c m3 / q , p r e s s u r e( Mb a r ) , < t e mp e r a t u r e ( K ) , v e l o c i t y ( c m/ ~ s ) . and h e a t c a p a c i t y ( c a l / g - K~ .

    T AB L E A IEQUAT I Of i OF S T A T E P L ! 7 AVE T E 2 S

    PBX 9 5 0 1

    2 9 5 0 0 @o o o o o o o c E - o lZoltooooooooooc+oc-lo7362$e~cl ~ooE+ol-l oll107s475$OCE+02-1.941e 53902200:+02lc418535G26@OOE+02-3.35G704$07400fc+ol105CCOOCOOOOOOF+OC3oOOOO090~OOOOE-015.45553737040CE-011 . COCCOCCCOCOCE - C4

    3 0 5 2 5@? 2 E J 4 0 t J O OE + O0- 2 . 6 0 2 0 9 4 1 5 2 6 0 0 E+ O02 . t 1 5 6 5 7 C5 8 b OOE - 0 1

    Slce;4 . 5 ~ o ~ o ~ o@o o ~ ~ - o l Ji.5100000000clK+oo Y- 3 . GE? 3 &2 5 8 7 4 S3 r + 0 3 c 7 . 0 3 2 1 1 9 5 4 0 &4 E+ 0 3 v- 4 . E 2 6 7 0 2 1 3 E! 9 CI I L +0 3 u

    j.4&6?e~~~l18E+03

    3 , 0 4 3 2 15 4 9 3 50 0 ~ - 0 2- 1 0 e 3 2 $5 3 \ t l t CCE - ( ? 1 0 6 1 2 2 1 3 7 3 4 4 OOE * OG5 . 2 T 5 1 1 7 5 4 ? 2 0CC- 0 17 0 0 2 4 3 Q4 3 2 ? 5 0 0 E- 0 24 . 6 4 3 G2 4 9 5 2 0 0 0 E- 0 31 0 2 3 4 1 3 9 6 3 5 4 OOF - O47 . 3 6 t ) 2 b Ot 5 t 3 0 0 E+ OC- 5 . c e t 7 0 c ] 6 e 3 c c f - c l3 . 5 5 3 5 t ) 8 ? 3 0b Oi ) C- 0 23 . Q4 2 2 4 2 ~ 4 4 1 0 0 E- 0 2 1 0 3 6 7 3 E I OC2 7 3 O OE - O25 . CCCCGOCOOOOC [ - C 11.00@0OOOOOOOOE-01

    - 1 . 6 6 3 9 1 6 1 S$ 1 8 3 ~ + 0 3. 2 . 0 0 0 0 OOOCI OOOE + OO1 . 0 7 00 0 00 0 0 0 0 C- CI 11 . 2 6 3 1 0 4 7 1 1 OOE , - O Il Q1 7 00 0 01 3 0 0 0 f l E - 0 5

    UN CL A S SI F I E D

  • 8/3/2019 G. Edward Cort and Jerry H. Fu- Numerical Calculation of Shock-Induced Initiation of Detonation

    10/19

    UNCLASSIFIEDT ABL E A- 1 , EQUAT I ON OF S r AT E PARAMET ERS - CONT I NUED

    Air- 4 . 5 0 6 0 2 5 4 2 6 ES~ + O0-1.275461 !0628~+O0- 3 . 7 4 Z 7 6 6 0 0 2 WE - 0 31 - Z 3 9 2 9 2 3 6 7 4 7 C- 02- 2 . 0 7 6 9 41 E2 9 2 9 E- 0 3=1.626S544743SE+O09.052~314661SE-022.69OO4997?26E-O3- S . 4 3 S8 3 1 Z Z1 9 2 E- 0 5

    o@nsTuGzu

    -1.5852189533@~-06em2~64~5~1441E+oo

    --2.!51525130950E-01-1.3444694004?~-021.40871O16422E-O2a.1813?18~~85P03s.o~oooooooooE-oll.OOOo~ooooooE-ol@ 6 5 2 2 4 0 0 0 0 0 0 E+ 0 2

    APPENDI X BF OREST F I RE BURN RAT E

    T h e ma s s f r a c t i o n o f u n b u r n e d e x p l o s i v e U + s d e f i n e d a s W = 1 f o r p u r es o l i d , a n d b u r n s t o gaseous p r o d u c t s , U = O, a c c o r d i n g t o ap r e s s u r e - d e p e n d e n + , r a t e l a w b a s e d o n e x p e r i me n t a l d a t a . l S 2 T h e r a t e R i sd e f i n e d f o r p r e s s u r e P i n M9 a r s a n d t i me t i n u s b y

    R. (l/W) (dbJ/dt).

    T h e l i mi t i n g c o n d i t i o n s s e t R . 0 f o r P l e s s t h a n a s p e c i f i e d c u t o f fp r e s s J r e a n d R = I ( U q O i mme d i a t e l y ) wh e n P r e a c h e s t h e C- J p r e s s u r e . Th er a t e p a r a me t e r s u s e d i n t h i s s t u d y a r e t a b u l a t e d i n T a b l e B - I .

    T ABL E B - IF CM? E ST F I RE RAT E P ARA ME TE RS

    PBX 9 5 0 1

    C-J PRESSUQ[ q 003595 CUT-~F PRESSURE q CoCC5

    UNCLASSIFIED

  • 8/3/2019 G. Edward Cort and Jerry H. Fu- Numerical Calculation of Shock-Induced Initiation of Detonation

    11/19

    UNCLASSIFIEDT h e s e F o r e s t F i r e p a r a mt e r s a r e d e r i v e d f r o m t h e e x p e r i n wn t a l l yd e t e r mi n e d Po p p l o t s . T h e e q u a t i o n o f t h e Po p p l o t i s! L n x = A+ B? . n P ,

    wi t h t h e r un d i s t a n c e x i n c m a n d t h e p r e s s u r e P i n Mb a r s . I l l e Po p p l o t sa r e s h o wn i n F i g . 1 . T h e p a r a me t e r s a r e g i . ~ e n i n T a b l e B - I I .

    T A B LE B-IIP OP - P L OT P AR AME T ER S

    / ! B. PPX 9501 -500B27PB~lJ -1.475245725

    REFERENCES1. C. L . Ma d e r a n d C. A . F o r e s t . T wo - D i mn s i o n a l Ho n wg e n e o u s a n dH~ t e r o g e n e o u s De t o n a t i o n Wa v e F r o p a g a t i o n , L o s A l a mo s Sc i e n t i f i cL a b o r a t o r y r ? p o r t L A - 6 2 5 9 ( 1 9 7 6 ) .2 . C. L . Ma d e r , Nu me r i c a l Mo d e l i n g o f De t o n a t i o n s ( Un i v e r s i t y o fCa l i f o r n i a P r e s s , Be r k e l e y , 1 9 7 9 ) .3. J . D. Ke r s h n e r a n d C. L . Ma d e r , Z DE , A T wo - Di me n s i o n a l c o n t i n u o u sEu l e r i a n Hy d r o d y n a mi c Co d e f o r Co mp u t i n g Mu l t i c o mp c n e n t Re a c t i v e

    Hy d r o d y n a mi c P r o b l e ms , L o s A l a mo s Sc i e n t i f i c L a b o r a t o r y r e p o r tL A - 4 8 4 6 ( Ma r c h 1 9 7 2 ) .

    UNCLASSIFIED

  • 8/3/2019 G. Edward Cort and Jerry H. Fu- Numerical Calculation of Shock-Induced Initiation of Detonation

    12/19

    UNCLASSIFIED

    2f.1.o*lo

    I 0.0

    16.0z= 14.0h.=gv 12.0>xu0 100$

    0.0

    60*103

    100.0 ~ I I I I I 1 1 1 1 1 1 , I I\!k~x&~)cn\3(l~5.31bm/ff3)PBA 9501\ ~. 1.833q/crn3(114,6 lbm /f!3)10 100

    Pressure (h bor)~--lI Procswe ( GP o)

    F i q u r e 1 . Po p P l o t s f o r PEX 9 5 0 1 a n d PBX 9 4 0 4

    6 0 ~ ; T ~&& L #- ##// /# /

    24 ,5 - /a /w ! g 4 0

    ~ L e g e n d~ 3 . 5- //u A 9 0 0 - 1 0 p ~ l B6 T g \ Cms ( 1 1 6 7l & l b m/ f 1 3 )* I PBX S5 01 p . 1 8 3 3 q / c m~ ( l1 4 6Ml @ b m/ f l s )u x PBX 9 4 0 4 p = l ,844g/cm(1 15?lXldlbm/fl)2.51

    2.0 1 1 1 1 I 1 1 J~. -J0.0 Q2 0.4 0.6 0.8 I.O 1.2 14 !.6 18 20Pa r t i c l eVe l o c i t yk m/ s1 I L 1 1 I I0.0 Imo 2000 3000 40 W 6 0 0 0 6000Pa r t i c l eVe l o c i t y t i s

    F i g u r e 2 , Sh o c k - Pa r t i c l e Ve l o c i t y Re l a t i o n f o r 9 0 0 - 1 0 ,PBX 9 5 0 1 , a n d PBX 9 4 0 4

    UNCLASSIFIED

  • 8/3/2019 G. Edward Cort and Jerry H. Fu- Numerical Calculation of Shock-Induced Initiation of Detonation

    13/19

    UNCLASSIFIED. . . . . ----- ----- ----- -----A i r

    1 2 0 i

    T a r g e l PB x 9 5 0 1

    or20 4(3 60Nu mb e r o f Ce l l sm t ? -Dwe ~ i l o nF i q u r e 3 , T y p i c a l Co mp u t e r Ho d e lf o r a n I mp i n q i n qCy l i n d r i c i l l P r o j e c t i l e.

    . . . . . . . . . .

    F i ~ u r e 5 . Ca l c u l a t e d I s o b a r s, a t 1 , 9 1 ; , s A f t e r I r l p a c t l ~ y7 , 6 2 mm ( 0 , 3 0 i n , ) - d i a r lCy l i n d e r z t 8 4 5 m/ ~( 2 7 7 ? f t / s )o i ! ( J

    [

    - ~ ~ - - - - , . ~ . . .. . . . , , . ~7

    b ( l- - - - - l i u q On , O lt F s s u r c0 0 5 . ,- - - - - - - - - - - - - - . , . - . . . - . - ! , ( )= \t PIQSt UIC lt)(lJ(. ) 10,- -.

    ~ 0(.)4 y \o----- tnc4Bp5~ - 4( I :?-. .-! fu95p50 q\ \, -Q1

    i 003 , --. t.143psk

    ; l~191ps- 30 $

    \\ t= 002i

    \ :() t2UI

    001 1( I\

    00 050 055 060 ~ ()0b5 070 07!t 080 Oe!l owlD1 8 1 0 n c ol o n g2 - QE I SI n12 14 16 18 2(.) 22lhnlanc~ A l o n gZ - o R I s mm)

    ~ i g u r e 4 , Ca l c u l a t e d P r e s s u r e A l o n q Cc n t c r l i n r f o r 7 , 6 7 - 1 1 1 1 : 1( 0 , 3 0 i n m) - d i n m Cy l i n d e r I mp a c t . o n ! I OO- 1 0 ill. N4L 111/5( 2 7 7 2 f t / s ) a t V a r i o u s T i me r A f t e r i ml ) , ~ ( tUNC L A SS I F I E D

  • 8/3/2019 G. Edward Cort and Jerry H. Fu- Numerical Calculation of Shock-Induced Initiation of Detonation

    14/19

    UNCLASSIFIED

    045 C50 0.55 0.60 065 0,70 075 060 0.851Dlstanca A l o n g t h e Z-aals(in.)

    12 14. 16 le . 20. 22.Distonce A l o n g t h e Z-a~is(mm)

    Fiqure 6, Calculated P r e s : u r a a n d ! J n b u r n e d Na s s F r a c t i o n f o r 7 , 6 ? i:w(0.30 i n , ) - d i a m Cy l i n d e r I mp a c t o n PBX 9 5 0 1 a t 8 4 5 n ! s( 2 7 7 2 f t . ); ) , l , q l ; ; s Af t e r I mp a c t

    3w: , . , 0 . ., ., ., ,0.,

    ,q

    _r :0..Q ,.0, .,, ,0

    r g u r [ ? 7 . Ca l c u l ~ t e d I s o b a r s I n PRX 9 5 0 1 a t l , q l( 0 , 3 0 I n ) - d l r i m Cy l i n d e r a t f M5 m/ s ( 2 7 7 2 f t / s )UNCLASSIFIED

  • 8/3/2019 G. Edward Cort and Jerry H. Fu- Numerical Calculation of Shock-Induced Initiation of Detonation

    15/19

    UNCLASSIFIEDI

    t, 1

    I

    I

    I1

    I

    III

    II

    \

    II

    [, I

    h-~

  • 8/3/2019 G. Edward Cort and Jerry H. Fu- Numerical Calculation of Shock-Induced Initiation of Detonation

    16/19

    UNCLASSIFIED

    na 1 , . a 2 a 8 # A l i l . 1.- 1.

    Dislonc~ From Imhal Inlwfacc(mm)i I 1 1 10 01 02 03 0.4 -Dmlonc@rrom Imllol Inl.rfoc@ [In J

    F i g u r e 9 . P r e s s u r e a n d Un b u r n e d ! l a s s F r a c t i o n F o r 7 , 6 2 mm[ n . 3 0 i n . ) . . d i a mCy l i n d e r I mp a c t a t 8 7 3 mi s ( 2 8 6 4 f t l s )b r I

    , ?

    ..,L_-J I00 Od 00 . 1? It r (1Tlmt Nw Impocl (p S1

    Fig~rc 10, Shock ~ront Pressure il:~S.,\li Time for lmpnct l~y :1,.l!i mm(0.13 in, )-diwn CylinderUNCLASSIFIED

  • 8/3/2019 G. Edward Cort and Jerry H. Fu- Numerical Calculation of Shock-Induced Initiation of Detonation

    17/19

    UNCLASSIFIED. ----- - .- --- -- . . .. .. . . .. .,. .

    . ....... 1 :-.

    Pm~.:-...-!-$4 . :.:.. .. ...;-$x,....... ....-.. .-.-m. . . . .?.- : ... . . . . . ./;?/ / .,:.m. . %. .., . .. . . . r: . .: . .:.,, ,.. I,-,1 j # : m: . . . : m.mm d . . ( . . - . . . t i . ~ 1.. ...-

    --.-- . ------- . . . . . .. ...... ,.........

    f .:......:$:Q... . .

    .. . .. . ..:. . r : , ,, ., .. . , .. ... . . , ,# . , ,c ?. . . : .;1 ,,.q . . . . .- ;4+;.XX

    ..,.....:48 ,, , . m, . .:. m :.. ,,,, ,,*.j,..,~:,~ .dm i :..-

    I

    Ii..

    *,.. .f

    a . . . . . . .l . ,,,,,11.., , iUNCLASSIFIED

  • 8/3/2019 G. Edward Cort and Jerry H. Fu- Numerical Calculation of Shock-Induced Initiation of Detonation

    18/19

    UNCLASSIFIED

    .-..---4!.,---.-_.-.J?!!2!%-----..........___..I

    r?[lJNCIASSIFIED

  • 8/3/2019 G. Edward Cort and Jerry H. Fu- Numerical Calculation of Shock-Induced Initiation of Detonation

    19/19