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The 18100 kg/sec mass flow of fluid produces a total brake power of 6 200Kw. It is proposed to install two turbines, one of which is twice the capacity of the other. The efficiency and specific speed of both units are assumed to be 85% and 70rpm respectively. Find the rotative speed of the turbine which has a bigger capacity

User AVK
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Final answer:

To find the rotative speed of the turbine with a bigger capacity, we can use the equation for specific speed.

Step-by-step explanation:

To find the rotative speed of the turbine with a bigger capacity, we need to use the equation for specific speed:



Specific Speed (Ns) = (N √Q) / H^0.75



Where N is the rotational speed, Q is the flow rate, and H is the head or power.



Since we know the specific speed is 70 rpm and the flow rate is 18100 kg/sec, we can rearrange the equation to find N:



N = (Ns * √Q) / H^0.75



Assuming the efficiency is the same for both turbines, we can use this equation to find the rotative speed of the turbine with a bigger capacity.

User Jotacor
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