Explanation Write the expression for the energy balance equation. E in − E out = Δ E system (I) Here, the total energy entering the system is E in , the total energy leaving the system is E out , and the change in the total energy of the system is Δ E system . Substitute Q in for E in , W b , o u t for E out , and Δ U for Δ E system in Equation (I) Q i n − W b , o u t = Δ U Q i n = m ( u 3 − u 1 ) + W b , o u t (II) Here, the mass of the piston cylinder device is m , the final specific internal energy is u 3 , the initial specific internal energy is u 1 , and the work done during the process is W b , o u t . Determine the initial volume of the air. ν 1 = m R T 1 P 1 (III) Here, the mass of a piston-cylinder device is m , the initial pressure of a piston-cylinder device is P 1 , the initial temperature is T 1 , and the universal gas constant for air is R . Calculate the final volume which is doubles of initial volume. ν 3 = 2 × ν 1 (IV) Determine the final temperature of an ideal gas for polytrophic process. P 1 ν 1 T 1 = P 3 ν 3 T 3 T 3 = P 3 ν 3 P 1 ν 1 T 1 (V) Here, the initial pressure of air is P 1 , the final pressure of air is P 3 , the initial volume of air is ν 1 , and the final volume of air is ν 3 . Determine the work done during the constant pressure process. W b , o u t = ∫ 1 2 P d ν = P ( ν 3 − ν 1 ) (VI) Conclusion: From the Table A-1, “Molar mass, gas constant, and critical-point properties” to obtain the value of gas constant for air as 0.2870 kJ / kg ⋅ K . Substitute 3 kg for m , 0.2870 kJ / kg ⋅ K for R, 27 ° C for T 1 , and 200 kPa for P 1 in Equation (I). ν 1 = ( 3 kg ) ( 0.2870 kJ / kg ⋅ K ) ( 27 ° C ) 200 kPa = ( 0.861 kJ / kg ⋅ K × ( 1 kPa ⋅ m 3 1 kJ ) ) ( 27 ° C+273 ) 200 kPa = 258

CONNECT FOR THERMODYNAMICS: AN ENGINEERI

9th Edition

ISBN: 9781260048636

Author: CENGEL

Publisher: MCG

See similar textbooks

Concept explainers

Work and Heat Transfer

It is generally related to thermal engineering which tells about the use, creation, conversion and transfer of heat energy between the systems. It is also considered that to transfer heat from one source to another, transfer of masses is also required. T…

Videos

Question

Chapter 4.5, Problem 79P

To determine

The work done by the air.

The heat transfer to the air during this process.

Expert Solution & Answer

Want to see the full answer?

Check out a sample textbook solution

See solution

Chapter 4.5, Problem 78P

Chapter 4.5, Problem 80P

Students have asked these similar questions

A cylinder-piston device contains 0.5 m3 of air at 150 kPa and 20 ° C. The gas is compressed in a polytropic process up to 400 kPa and 140 ° C. Show the process on a P-V diagram and determine the heat transfer and the work done during the process.

A piston–cylinder device contains 0.05 m3 of a gas initially at 200 kPa. At this state, a linear spring that has a spring constant of 150 kN/m is touching the piston but exerting no force on it. Now heat is transferred to the gas, causing the piston to rise and to compress the spring until the volume inside the cylinder doubles. If the cross-sectional area of the piston is 0.25 m2, determine (a) the final pressure inside the cylinder, (b) the total work done by the gas, and (c) the fraction of this work done against the spring to compress it.

A piston–cylinder device, whose piston is resting on a set of stops, initially contains 3 kg of air at 200 kPa and 27°C. The mass of the piston is such that a pressure of 400 kPa is required to move it. Heat is now transferred to the air until its volume doubles. Determine the work done by the air and the total heat transferred to the air during this process. Also show the process on a P-v diagram.

Chapter 4 Solutions

CONNECT FOR THERMODYNAMICS: AN ENGINEERI

Ch. 4.5 - Is the boundary work associated with...Ch. 4.5 - On a P-V diagram, what does the area under the...Ch. 4.5 - An ideal gas at a given state expands to a fixed...Ch. 4.5 - Calculate the total work, in kJ, for process 13...Ch. 4.5 - Calculate the total work, in Btu, produced by the...Ch. 4.5 - Nitrogen at an initial state of 300 K, 150 kPa,...Ch. 4.5 - The volume of 1 kg of helium in a pistoncylinder...Ch. 4.5 - A pistoncylinder device with a set of stops...Ch. 4.5 - A mass of 5 kg of saturated water vapor at 150 kPa...Ch. 4.5 - A frictionless pistoncylinder device contains 16...

Knowledge Booster

Learn more about

Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, mechanical-engineering and related others by exploring similar questions and additional content below.

The work done by the air. The heat transfer to the air during this process.