Question

Match the correct items in Column 1 with Column 2: 
\[\begin{array}{|c|c|} \hline \textbf{Column 1} & \textbf{Column 2} \\ \hline \text{P: Pipe-in-pipe heat exchanger} & \text{1: Cooling of air} \\ \hline \text{Q: Shell and tube heat exchanger} & \text{2: Simultaneous co-current and counter-current heat exchange} \\ \hline \text{R: 1-2 shell and tube heat exchanger} & \text{3: Large flow rate} \\ \hline \text{S: Cross flow heat exchanger} & \text{4: Small heat exchange area} \\ \hline \end{array}\]

• A. P-1, Q-2, R-4, S-3
• B. P-2, Q-3, R-4, S-1
• C. P-3, Q-4, R-2, S-1
• D. P-4, Q-3, R-2, S-1

Hint:

Shell-and-tube exchangers are standard for large flow rates; cross-flow exchangers often cool gases like air.

Answer 1

The Correct Option is D

Step 1: Understanding each exchanger.
P: Pipe-in-pipe → small heat transfer area → matches (4).
Q: Shell and tube → large flow rate capacity → matches (3).
R: 1–2 shell and tube → has one shell pass and two tube passes → allows both co-current and counter-current → matches (2).
S: Cross flow → typically used for cooling of air (e.g., radiators) → matches (1).

Step 2: Final matching. \[ P-4,\ Q-3,\ R-2,\ S-1 \] This corresponds to option (D).