Chapter 6, Problem 6.78P

In a steam engine cylinder 0.15 kg of steam at 10 bar and 250 0C expands to a pressure of 1 bar. If the quality of the steam at the end of expansion is 0.8, find the work output from the cylinder. Assume that the engine is well insulated.

Consider a two-part process with an expansion from 0.1 to 0.2 m' at a constant pressure of 150 kPa followed by an expansion from 0.2 to 0.4 m3 with a linearly rising pressure from 150 kPa ending at 300 kPa. Show the process in a P-V diagram and find the boundary work.

A piston/cylinder device contains 0.1 kg of air at 300 K and 100 kPa. The air is now slowly com- pressed in an isothermal (T = constant) process to a final pressure of 250 kPa. Show the process in a P-V diagram, and find both the work and heat transfer in the process.

A certain gas with One kilogram of mass, 100 kPa and 45°C is compressed adiabatically until the volume is minimizes to one sixteenth of its original rate. So, heat is further at persistent pressure until the temperature is 1450 °C. The gas is then extended adiabatically till to its initial volume is got and lastly it is cooled at constant volume till the original state of 100 kPa and 1450 °C is reached. Calculate the work done, internal energy and heat transferred for each process. [Take y = 1.4, Cp = 1.004 kJ/kg.K]

1. A vertical cylinder fitted with a piston contains 5 (kg) of R134a at 12°C. Heat is transferred at constant pressure causing the piston to rise until it hits a set of stops at which point the volume is doubled. Additional heat is added at constant volume to raise the temperature to 70°C and pressure to 1.4 MPa. Sketch the process on Pv and Tv diagrams. Find the heat transfer and work done for both processes. Ignore kinetic and potential effects.

A gas has a volume

Consider a balloon contains initially 40 liter of Helium at 105 kPa and 20 oC, The balloonis connected to a supply line of helium through a valve that is opened allowing helium tofurther fill the balloon to 150 kPa such that pressure in the balloon is expressed as: P =750 V0.5– 45, Where P is in kPa and V is m3. Considering Helium as ideal gas:a- Find the mass of Helium entered the balloon if the process is isothermal.b- Find the work done during the process.

In a refrigeration plant there is a 10-Liter rigid tank that contains R-410A at -10°C, 80% quality. Electric work in the amount of 36 kJ is added to the R-410A, after which the R-410A temperature reaches 40°C. Calculate the heat transfer and determine if the heat transfer is to or from the tank during this process? Qualitatively draw the process in a p-v diagram.

A certain quantity of air in a closed vessel with a fixed volume of 0.15 m3 exerts 1 MPa pressure at 500 K. If the vessel is cooled while the pressure is reduced to 350 kPa, find the steady-flow work during the process