A three dimensional representation of fluid flow induced in ladles or holding vessels by the action of liquid metal jets
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SALCUDEAN
AND
RODERICK
I. L. GUTHRIE
A t h r e e d i m e n s i o n a l flow m o d e l is p r o p o s e d f o r d e s c r i b i n g the r e c i r c u l a t o r y flow p a t t e r n s g e n e r a t e d by c o h e r e n t j e t s of m e t a l e n t e r i n g l a d l e s o r holding v e s s e l s . B a s e d on p r e v i o u s l a m i n a r and t u r b u l e n t flow m o d e l s 1'2 d e v e l o p e d for a x i s y m m e t r i c c o n d i t i o n s , i t w a s d e c i d e d that a t r a n s i e n t t h r e e d i m e n s i o n a l , l a m i n a r flow m o d e l was b e s t s u i t e d to p r e d i c t the effect of j e t angle, j e t l o c a t i o n and ladle a s p e c t r a t i o on r e s u l t i n g flow p a t t e r n s . It is shown that the l a d l e ' s s h a p e and the j e t s l o c a t i o n and e n t r y angle a r e c r i t i c a l in e s t a b l i s h i n g the n a t u r e of the r e c i r c u l a t i n g flow p a t t e r n s , and that in s o m e i n s t a n c e s , s u r f a c e flow a l o n g the m i n o r a x i s can r e v e r s e .
THERE
a r e many i n s t a n c e s in which the e n t r y of liquid m e t a l j e t s into holding v e s s e l s r e s u l t in the g e n e r a t i o n of r e c i r c u l a t o r y flow p a t t e r n s . Thus, the e n t r y of liquid j e t s of s t e e l into t e e m i n g l a d l e s , of t e e m i n g j e t s into t u n d i s h e s and of t u n d i s h j e t s into c o n c a s t i n g m o l d s a r e a l l c l a s s i c e x a m p l e s . In p r a c t i c e , t h e s e j e t s often e n t e r in a n o n a x i s y m m e t r i c m a n n e r . F o r i n s t a n c e , in the c a s e of l a d l e f i l l i n g o p e r a t i o n s , the j e t n o r m a l l y e n t e r s at an angle to the v e r t i c a l while the l a d l e into which it f i l l s can often be e l l i p t i c a l o r e l o n g a t e d r a t h e r than c i r c u l a r . S i m i l a r l y , in the c a s e of a liquid j e t e n t e r i n g a t u n d i s h o r i s s u i n g f r o m a s u b m e r g e d t u n d i s h n o z z l e into a c o n c a s t l a d l e , the flow is a g a i n u s u a l l y t h r e e d i m e n s i o n a l in c h a r a c t e r . F o r t h e s e r e a s o n s , a t h r e e d i m e n s i o n a l fluid flow m o d e l has b e e n d e v e l o p e d to t r e a t the e n t r y of n o n v e r t i c a l s i n g l e liquid m e t a l j e t s into r e c t a n g u l a r c a v i t i e s . Since the m a i n o b j e c t i v e of the p r e s ent w o r k was to d e s c r i b e bulk fluid flow p a t t e r n s r a t h e r than l o c a l v a r i a t i o n s in t u r b u l e n c e e n e r g y l e v e l s , a t r a n s i e n t l a m i n a r flow m o d e l was c h o s e n t o g e t h e r with a r e c t a n g u l a r c o o r d i n a t e s y s t e m . The v a l i d i t y of t h i s t h r e e d i m e n s i o n a l l a m i n a r r e presentation is discussed later.
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