The Reynolds Transport Theorenm 2 In an internal combustion

The Reynolds Transport Theorenm 2. In an internal combustion engine of a car, the ignition and combustion (burning) of the fuel occurs within the engine and the engine then partially converts the energy from the combustion to work. The engine consists of a fixed cylinder and a moving piston and requires four position strokes to complete a cycle - intake, compression, combustion & power stroke, and exhaust. The fuel is mixed with air and then introduced into the cylinder during the intake process. After the piston compresses the fuel-air mixture, the spark ignites it, causing the combustion. The expansion of the combustion gases pushes the piston down during the power stroke. Finally, the combustion gases are released from the cylinder during the exhaust process is purs.coRM sant-nd ternal combustion engine work Consider the compression process when the piston in the cylinder is moving up (see the figure below). Control Surface Cylinder Piston Control Volume Crankshaft Piston is moving up ward CVEN 311-502 Spring 2018_Homework7 Page I of 3 For the given instance of time during the compression process, indicate which of the following statements are true. Clearly justify your answers. (10 points) CS B. JcvpdW is equal to zero C. The density of the gas in the control volume is increasing with time D. The temperature of the gas in the control volume is increasing with time E. The flow inside the control volume is unsteady

Solution

Answer(A)-True

The net flow rate of linear momentum out of the control surface by mass flow is zero because no outlet.

Answer(B)-False

The time rate of change of the linear momentum of the contents of the CV can not be zero.

Answer(C)-True

it is a closed volume with no outlet hence after compression mass will increse so density will increse.

Answer(D)-True

it is a closed volume with no outlet hence after compression molecular will come closure and collide that will increse the temp. inside the cylinder.

Answer(E)-True

hence there is no outlet ,gas is compressed so flow is unsteady.