HOW DOES THE INWARD FLOW REACTION TURBINE WORKS?


THE INWARD FLOW REACTION TURBINE
In the previous blog we discussed about the outward flow reaction turbine and in this blog we will discuss about the inward flow reaction turbine in detail.
Well, the inward flow reaction turbine is similar to the outward flow reaction turbine but the difference is that, in this turbine the guide vanes surround the moving vanes. The next reason for preferring the inward flow reaction turbine than the outward flow reaction turbine is that it does not create racing and hence it is easy to control the speed.
The inward flow reaction turbine consists of the shaft, a cylindrical disc and vanes attached to the periphery of the wheel as shown in the figure below ( fig : 1). The flowing water enters the vanes through the guide vanes and after gliding through the guide vanes it enters to the outer periphery of the wheel of the diameter ‘D’. After water moves through the outer periphery of the wheel then it is discharged into the inner periphery of the wheel of the diameter ‘D1’.
So the thing that is to be taken into account is that external diameter is the inlet point and hence the inlet diameter and internal diameter is the outlet diameter in the inward flow reaction turbine.
                                                            fig : 1
Now let us suppose that XY is one of the vanes where X is the inlet point and Y is the outlet point. The peripheral velocity at the inlet point X be ‘a’ which is along the tangent line through the point X and the peripheral velocity at the outlet point Y be’a1’ which is along the tangent line through the point Y at outlet. From the figure ( fig: 2 and fig: 3) we can notice that ‘a’ and ‘a1’ are not in the same direction though it is not necessary in every case but in this case it is not in the same direction. So, we can see in Fig : 4, which is the representation diagram for the fig : 2 and fig : 3, that the direction of the both the periphery velocities have been kept the same. The diagram appears to be shifted but the sides and angles remain unaffected.
                                                        fig: 2

                                                      fig: 3

                                                     fig: 4
Here,
a= periphery velocity of the wheel at inlet at point X
a1= periphery velocity of the wheel at outlet at point Y
b= relative velocity of wheel at inlet X
b1= relative velocity of wheel at outlet Y
v =absolute velocity of water at point X
v1= absolute velocity of water at point Y
c= velocity of water flow at X
c1= velocity of water flow at point of outlet of vane XY at Y
e= velocity of whirl at inlet X
e1= velocity of whirl at outlet Y
N= speed of the wheel in rpm
D= inlet diameter of the wheel (runner)
D1= outlet diameter of the wheel (runner)
B= breadth of the wheel at the inlet
B1= breadth of the wheel at the outlet
HOW TO CALCULATE THE DISCHARGE OF THE TURBINE?
Q= radial area at inlet * radial velocity at inlet = radial area at outlet *radial velocity at outlets
      =∏ *D* B *C = ∏* D1*B1*C1
But while calculating the total discharge of the turbine, some space is considered for the blades of the turbines.  4% to 5% of the total space is occupied by the blades of the turbines. So, the total discharge becomes
 Q= 0.95* ∏*D*B*C = 0.95*∏*D1*B1*C1
HOW TO CALCULATE THE PERIPHERY VELOCITIES OF THE WHEEL??
Periphery velocity at the inlet ‘a’ = (∏*D*N)/60
Periphery velocity at the outlet ‘a1’ = (∏*D1*N)/60
HOW TO CALCULATE HEAD ON THE TURBINE??
Head at the inlet of the turbine= total head at the source i.e. reservoir or dam – frictional losses and other losses in the pipes
HOW TO CALCULATE THE POWER OF THE TURBINE?
Water power (W.P): The power supplied at the inlet of the turbine is called water power. Mathematically,
                                 W.P. = (9810*Q*H)/1000
The unit when above formula is used should be in Kilowatts (KW).
H= head at the inlet of the turbine
Q= discharge of the turbine
Runner power (R.P.) = the power developed by the wheel or the runner is called the runner power.
                                 R.P. = [ { W * ( e * a – e1 * a1 ) } / g * 1000]
The unit is in Kilowatts (KW).
Shaft power or brake power = runner power – power lost in mechanical resistance
HOW TO CALCULATE THE EFFICIENCY OF THE TURBINE?
The efficiency of the turbine can be calculated as following:
1)    Hydraulic efficiency= R.P. /W.P.
2)    Mechanical efficiency = ( e * a – e1 * a1 ) / ( g * H)
Where, H = head of the turbine at the inlet
3)    Overall efficiency = S.P. / W.P.
4)    Volumetric efficiency = Q / (Q+Q1) where, Q= quantity of water flowing through the runner and Q1 = quantity of water lost due to the slip
                                               
                                                                                                          THANK YOU
 NOTE: Discrimination and choices are two completely different things. Discrimination may have choices but choices do not have discrimination. It is never my intention to hurt someone's feeling, emotions and pride. Above material is solely just for entertainment purpose only and should be taken light heartedly.
Finally we all are humans. Humans have different physical forms and mental forms and should be respected no matter what. Abusing in any form whether it be verbal, emotional or physical surely is a criminal act that deserves serious attention with punishment. In other hand, jokes and comedy are completely different things which should exist within the circle of loved and near ones and can be extended to some extent beyond the limits but surely we need to be conscious towards the fact that our loved ones are not hurt by our words and actions. Peace, love and respect should not be destroyed to the extent that it becomes impossible to repair or rebuild.


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