Question

A closed thermodynamic system undergoes a process that takes it from State 1 to State 2. a) Write the equation that describes the change in total availability (maximum energy available to do useful work). b) Describe the meaning of each term in the equation.

Answer 1

Answer:

$A_1-A_2=\left (U_1+P_0V_1-T_0S_1 \right )-\left (U_2+P_0V_2-T_0S_2 \right )$

Explanation:

Lets take property of system

At state 1

$T_1 =temperature$

$U_1 =internal\ energy$

$V_1= Volume$

At state 2

$T_2=temperature$

$U_2=internal\ energy$

$V_2=Volume$

And the Surrounding have

$T_0 =temperature$

$P_ 0=pressure$

As we know that Availability of a close system given as follows

$A=U+P_0V-T_0S$

So change in availability of a close system

$A_1-A_2=\left (U_1+P_0V_1-T_0S_1 \right )-\left (U_2+P_0V_2-T_0S_2 \right )$

Where

$S_1-S_2\ is \ the\ entropy\ change\ of\ system\ from\ state\ 1\ to\ 2$