PSI - Issue 40

Natalya V. Burmasheva et al. / Procedia Structural Integrity 40 (2022) 82–89 Natalya V. Burmasheva, Evgeniy Yu. Prosviryakov / Structural Integrity Procedia 00 (2019) 000 – 000

86

5

Note also that the velocity V y = V retains its sign; therefore, the rotation of the fluid during its flow is possible only along the Ox axis. Let us analyze the velocity V x = U+uy further in detail. 3. Analysis of the exact solution For the convenience of the further analysis, we introduce two substitutions:

Z z h h =  . In this case, the exact solution (19) for the velocity components U , u , and V takes the form = , a

h u Z a

(

)

(

)

u

V V h + =

z

=

+

+

h

,

,

1

a

+

6

8

h U h

h h u V h

) (

) (

) (

)

(

) ( Z a a

)

(

2

 

 

2 1 4 6 1 a a + − − − + + Z a

2 2 a Z Z Za a

2 4 6 + + =

1 + + +

U

=

( 12 1

)

(

)

3

3

1

a

a

+

+

(

)

   

   

8

2

1 4 6 + +

h h u V h

a a

6

8

h U h

h h u V h

(

)

(

)

2 2 Z Z Za a + + 4 6

2

Z a

=

+ +

.

(10)

(

)

( 12 1

)

( 12 1

)

3

2

1

a

+

a

a

+

+

It can be seen from expression (10) that the velocity U profile is determined by the competitive interaction of two flows, one of which has a linear profile and the other is nonlinear. Moreover, if the coefficient in front of the nonlinear term in (10) is zero, the velocity

( 1 h U h U Z a a = + + ) ( 6

)

takes on values of only one sign. Let us see under what conditions the velocity can take on zero values. To do this, we select the nonlinear term:

(

)

   

   

   

8

2

1 4 6 + +

h h u V h

a a

8

) ( ) 1 h U h a  +  6

8

h h u V h

h h u V h

(

(

)

2 2 Z Z Za a

2 4 6 + + +

U

Z a

=

+ =

( 12 1

)

( 12 1

)

( 12 1

)

2

3

2

a

a

a

+

+

+

8

( 12 1 h h u V h Z Z Za a k Z a a   = + + + +   +  , ) ( ) 2 2 2 2 4 6

(

)

where

(

)

( 12 1

)

2

2

2

1 4 6 + +

h h h a U u V h − 

a a

+

k

=

.

(

) a u

2

1

V h

+

h h

The locus of points whose coordinates satisfy the condition

Made with FlippingBook - professional solution for displaying marketing and sales documents online