Rotating Horsepower

on . Posted in Fluid Dynamics

 Rotation horsepower, abbreviated as \(HP_r\), is converting the objects horsepower into rotational motion.

 

Rotating Horsepower formula

\(\large{ HP_r = \frac{ \tau \; s }{ 5252 } }\) 
Symbol English Metric
\(\large{ HP_r }\) = rotating horsepower \(\large{\frac{lbf-ft}{sec}}\) \(\large{\frac{Btu}{s}}\)
\(\large{s}\) = rotation shaft speed, RPM \(\large{\frac{ft}{sec}}\) \(\large{\frac{m}{s}}\)
\(\large{ \tau }\)  (Greek symbol tau) = torque \(\large{lbf-ft}\) \( N-m \)
  • \(\large{ 1 \; HP  =  5252\; RPM }\)   When charting torque and horsepower, the math always cross at 5252 RPM.

 

Rotating Horsepower formula

\(\large{ RHP =  \tau \; \frac{ s }{ 33,000 } \; 2 \; \pi }\) 
Symbol English Metric
\(\large{ HP_r }\) = rotating horsepower \(\large{\frac{lbf-ft}{sec}}\) \(\large{\frac{Btu}{s}}\)
\(\large{ \pi }\) = Pi \(\large{3.141 592 653 ...}\)
\(\large{s}\) = rotational shaft speed, RPM \(\large{\frac{ft}{sec}}\) \(\large{\frac{m}{s}}\)
\(\large{ \tau }\)  (Greek symbol tau) = torque \(\large{lbf-ft}\) \( N-m \)
  • \(\large{ 1 \; HP  =  33,000 \; \frac{lbm-ft}{min}  }\)

 

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Tags: Torque Equations Horsepower Equations