Question

In: Mechanical Engineering

An air engine is modeled after the ott cycle. Assume ideal gas and air standard cold...

An air engine is modeled after the ott cycle. Assume ideal gas and air standard cold valus for properties. Intake air is at 100kPa and Temperature of 27°C. The compression ration is 8:1. The heat added during ignition is 1740 kJ/kg
a) Draw and Label the Pv and Ts diagrams for the Otto cycle
b)Find the specific volume at intake state #1
c) Find the temperature at the end of the compression stroke
d) Find the Pressure at the end of the compression stroke
e) Calculate the efficiency for the cycle
f) For the Carnot air heat engine working between the same temperature resevoirs, what is the Carnot Efficiency

Solutions

Expert Solution


Related Solutions

An Otto Cycle engine operation at cold-air standard has a volume of 0.1908 at the beginning...
An Otto Cycle engine operation at cold-air standard has a volume of 0.1908 at the beginning of isentropic compression. If the compression ratio is 12.5, how much heat is released from the fuel per kg of fuel burned if the fuel consumption is 0.02 kg/min? The mean effective pressure is 350kPa.
A Dual cycle engine is analyzed using the cold air standard method. Given the conditions at...
A Dual cycle engine is analyzed using the cold air standard method. Given the conditions at state 1, compression ratio (r), and cutoff ratio (rc) determine the efficiency and other values listed below. Note: The specific heat ratio and gas constant for air are given as k=1.4 and R=0.287 kJ/kg-K respectively. Given Values T1 (K) = 316 P1 (kPa) = 170 r = 18 rp = 1.44 rc = 1.22 a) Determine the specific internal energy (kJ/kg) at state 1....
Air enters the compressor of an ideal cold air-standard Brayton cycle at 100 kPa, 300 K,...
Air enters the compressor of an ideal cold air-standard Brayton cycle at 100 kPa, 300 K, with a mass flow rate of 6 kg/s. The compressor pressure ratio is 10, and the turbine inlet temperature is 1400 K. For k = 1.4 and Cp = 1.005 kJ/kg, calculate: (a) the percent thermal efficiency of the cycle. (b) the back work ratio. (c) the net power developed, in kW
An ideal cold air-standard Otto cycle has a compression ratio of 9.2. At the end of...
An ideal cold air-standard Otto cycle has a compression ratio of 9.2. At the end of the expansion process, the pressure is 110 psi, the temperature is 1020 °R and the specific volume is 3.435 ft3/lbm. The heat rejection from the cycle is 92 BTU/lbm of air. Evaluate specific heat at 100 °F and calculate the following by hand: What is the mean effective pressure (psi)? The correct answer is 231.8 psi. Show every step and calculation with units necessary.to...
A gas turbine operates as a cold-air standard Brayton cycle. Air enetrs the compressor at 300K...
A gas turbine operates as a cold-air standard Brayton cycle. Air enetrs the compressor at 300K and 100kPa and is compressed to 700kPa. During the heat addition process in the combustor, the temperature of the air increases to 1000K. The turbine and compressor can be assumed to be operating isentropically. Evaluate specific heat at 300K. a. thermal efficiency of the cycle? b. net work of the cycle (kj/kg)? c. Back work ratio?
Consider an automobile engine which operates on the ideal Otto cycle. In this engine, air is...
Consider an automobile engine which operates on the ideal Otto cycle. In this engine, air is compressed with a compression ratio of 10. At the beginning of the compression process, air is at 105 kPa and 17oC, and in the combustion process 640 kJ/kg of heat is added to air. Taking into account the variation of specific heats with temperature, determine (a) the pressure and temperature at the end of the heat-addition (combustion) process, (b) the net work output, (c)...
What are the air-standard assumptions and the cold air-standard assumptions in analysing engine cycles? How an...
What are the air-standard assumptions and the cold air-standard assumptions in analysing engine cycles? How an actual combustion process is being simplified in ideal engine cycles?
A mole of an ideal gas goes through a cycle of a Carnot engine. Draw the...
A mole of an ideal gas goes through a cycle of a Carnot engine. Draw the pressure vs volume and entropy vs temperature planes for this cycle. What do the diagrams look like when the efficiency of the cycle is 50% and 99%. Then Calculate the work done per cycle by the gas and find the efficiency of the cycle.
A heat engine with a monatomic ideal gas reversibly goes through the following cycle. A ⟶...
A heat engine with a monatomic ideal gas reversibly goes through the following cycle. A ⟶ B is an isothermal process. B⟶ C is an isovolumetric process. C⟶ A is an adiabatic process. (i) Determine the work done on the ideal gas during each cycle of this heat engine, (ii) Determine the heat flow into the gas during each cycle of this heat engine (iii) Determine the net work done by one cycle (iv) Determine the efficiency of this heat...
Consider an ideal Brayton cycle with reheat (air standard). The pressure and temperature of the air...
Consider an ideal Brayton cycle with reheat (air standard). The pressure and temperature of the air at the inlet of the gas turbine is 1200 kPa and 1000 K respectively. Assume the gas expands to 100 kPa in two stages. Between the stages, the air is reheated at a constant pressure of 350 kPa to 1000 K. Assume a fully isentropic process in the turbines. Find: (a) the work produced at each stage, in kJ/kg of air flowing. (b) the...
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT