Question

# A flow idealized as a throttling process through a device has$\begin{array}{l l } \text{(a) h_{2}>h_{1} and p_{2}>p_{1}}\\ \text{(b) h_{2}=h_{1} and p_{2}>p_{1}}\\ \text{(c) h_{2}>h_{1} and p_{2}

Solution

Verified
Step 1
1 of 2

$\textbf{1.)}$In a steady-state, steady-flow process, significant changes in pressure and temperature can occur to the fluid, and yet the process will be $\textbf{isenthalpic}$ if there is no transfer of heat to or from the surroundings, no work done on or by the surroundings, and no change in the kinetic energy of the fluid.

$\textbf{2.)}$If a steady-state, steady-flow process is analysed using a control volume, everything outside the control volume is considered to be the surroundings..

$\textbf{3.)}$The throttling process is a good example of an $\textbf{isenthalpic process.}$ Consider the lifting of a relief valve or safety valve on a pressure vessel.

$\textbf{4.)}$ The specific enthalpy of the fluid inside the pressure vessel is the same as the specific enthalpy of the fluid as it escapes from the valve.

$\textbf{5.)}$With a knowledge of the specific enthalpy of the fluid and the pressure outside the pressure vessel, it is possible to determine the temperature and speed of the escaping fluid.

So, the answer is $\textbf{d.)}$ $h_{2}=h_{1}$ and $p_{2} , it is isenthalpic process but pressure reduces.

## Recommended textbook solutions #### Fundamentals of Electric Circuits

6th EditionISBN: 9780078028229 (12 more)Charles Alexander, Matthew Sadiku
2,120 solutions #### Physics for Scientists and Engineers: A Strategic Approach with Modern Physics

4th EditionISBN: 9780133942651 (5 more)Randall D. Knight
3,508 solutions  