Question

An axial compressor rotor has a blade hub to tip radius of with a mean radius of 0.3 m rotating at 6,500rpm. The stage is designed for a pressure ratio of 1.4 throughout the blade radius with a stage efficiency of 85%. The air enters the stage at static temperature of 290 K and static pressure of 100kPa. Air inters axially to the rotor with a velocity of 140 m/s. Consider constant axial velocity throughout the stage. If AirCp=1 kJ/kgK,R=0.287 kJ/kg.K, and γ=1.4, Find the power required to drive the rotor?

Answer 1

To calculate the power required to drive the rotor, we can use the formula: Power = Mass Flow Rate * Total Enthalpy Change.

Step-by-step explanation:

To calculate the power required to drive the rotor, we can use the formula:

Power = Mass Flow Rate * Total Enthalpy Change

First, we need to calculate the mass flow rate. The mass flow rate is given by:

Mass Flow Rate = Air Density * Axial Velocity * Area

Next, we need to calculate the total enthalpy change. The total enthalpy change is given by:

Total Enthalpy Change = Cp * (Tout - Tin)

Finally, the power required to drive the rotor is given by:

Power = Mass Flow Rate * Total Enthalpy Change

Based on the given values, we can substitute the values and calculate the power required to drive the rotor.