The design conditions for a fan–duct system are as follows: air temperature = 15°C, fan speed = 200 rpm, volume flow rate =5 m3 s í1 , pressure rise = 800 Pa. (i) Calculate the flow rate, the pressure...

The design conditions for a fan–duct system are as follows: air temperature = 15°C, fan speed = 200 rpm, volume flow rate =5 m3 s í1 , pressure rise = 800 Pa. (i) Calculate the flow rate, the pressure rise, and the power if the speed is decreased to 150 rpm at the same air temperature. (ii) Calculate the flow rate, the pressure rise, and the power if the air temperature is increased to 45°C with the speed at 200 rpm. (iii) Calculate the flow rate, the speed, and the power if the air temperature is increased to 45°C with the pressure rise remaining at 800 Pa.