1. A drying process is used to remove 3000 lbm/h of water (vapor) at steady-state from...

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1. A drying process is used to remove 3000 lbm/h of water (vapor) at steady-state from processed paper. The dryer first heats atmospheric air (state 1) at 80°F, 1 atm and 60% relative humidity to 250°F and 1 atm (state 2). The heated air then is passed over the paper where it leaves the dryer at 150°F, 1 atm and 30% relative humidity (state 3). Determine: (35 pts.) a) the required mass flow rate of air (lbm (air) per hour) b) the required heat transfer to the air for the process (in Btu/h) 2 paper 3 2. Gaseous octane (C8H18) enters the combustion chamber of a power plant and burns with 100% theoretical air entering at 25°C, 1 atm. The products exit the system at 627°C, 1 atm. If the rate of heat transfer from the system to the surroundings is estimated at 15% of the net power developed, determine the molar flowrate of fuel, in kmol/h, for a net power output of 1 MW. (30 pts.) 3. Consider a gas-turbine power plant that operates on an ideal cold-air standard Brayton cycle and delivers an output of 20 MW to the electrical generator. The minimum and maximum cycle temperatures are 520°R and 2700°R, respectively. The minimum and maximum cycle pressures are 14.0 and 140 psi, respectively. Determine: (35 pts.) a) the power output of the turbine and percent output required to drive the compressor b) the thermal efficiency of the cycle 1. A drying process is used to remove 3000 lbm/h of water (vapor) at steady-state from processed paper. The dryer first heats atmospheric air (state 1) at 80°F, 1 atm and 60% relative humidity to 250°F and 1 atm (state 2). The heated air then is passed over the paper where it leaves the dryer at 150°F, 1 atm and 30% relative humidity (state 3). Determine: (35 pts.) a) the required mass flow rate of air (lbm (air) per hour) b) the required heat transfer to the air for the process (in Btu/h) 2 paper 3 2. Gaseous octane (C8H18) enters the combustion chamber of a power plant and burns with 100% theoretical air entering at 25°C, 1 atm. The products exit the system at 627°C, 1 atm. If the rate of heat transfer from the system to the surroundings is estimated at 15% of the net power developed, determine the molar flowrate of fuel, in kmol/h, for a net power output of 1 MW. (30 pts.) 3. Consider a gas-turbine power plant that operates on an ideal cold-air standard Brayton cycle and delivers an output of 20 MW to the electrical generator. The minimum and maximum cycle temperatures are 520°R and 2700°R, respectively. The minimum and maximum cycle pressures are 14.0 and 140 psi, respectively. Determine: (35 pts.) a) the power output of the turbine and percent output required to drive the compressor b) the thermal efficiency of the cycle

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ANSWER 1 To determine the required mass flow rate of air lbmhr and the required heat transfer to the air Btuhr we can use psychrometric charts and apply the principles of psychrometrics which deal wit... View the full answer