Analysis of Radial Flow Reaction Turbines

 

Velocities at entrance (1) and exit (2) of vane on impeller:    V  =  U  +  W     where

 

                V  =  the absolute fluid velocity measured in the inertial frame of reference

                U  =  the velocity of the vane rotating about  the z-axis

               W  =  the velocity of the fluid relative to the vane

                                

 

where   er = unit vector in radial direction,          et = unit vector in tangential direction

              n1= unit vector along vane at the entrance (attached to vane)

              n2 = unit vector along vane at the exit (attached to vane)

               ω = absolute angular speed of impeller

            r1 = radius at entrance section of vane,  r2 = radius at exit section of vane

           V1 = absolute velocity of fluid striking the turbine at 1 at angle α1  

          β1  = angle of vane at entrance,  β2 = angle of vane at exit

 

At entrance 1:                                                                 At exit 2:

 

U1  =   ˗  r1 ω  et                                                          U2  =    ˗ r2 ω  et   

 

W1  =    ˗ w1   n1                                                        W2  =   ˗ w2  n2

 

V1  =  ˗ V1 cos α1  et  +  ˗ V1 sin α1  er                       V2  =   ˗ r2 ω  et   ˗ w2  n2

 

Click here for a display of the vector diagrams.

 

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