Parallel and Counterflow: Match the Temperature Pairing

Define the Thermal Model

Flow direction determines which terminal temperatures are adjacent. Alfa Laval’s plate-exchanger theory describes counter-current channel flow and its temperature program. Bulk outlet values at different physical ends are not a local temperature difference. Draw the streams before declaring a temperature cross impossible.

Compare a Hypothetical Case

Imagine hot fluid cooling from 80°C to 40°C while cold fluid heats from 20°C to 60°C. In counterflow, both local end differences are 20 K. With equal assumed heat-capacity rates, the energy changes also match. In parallel flow, the proposed outlet pair would be 40°C hot beside 60°C cold, reversing the intended local heat-transfer direction.

Complete the Engineering Review

Label inlet and outlet at each physical end rather than merely listing four numbers in a quote. Check the energy balance and both local terminal differences for the proposed arrangement. Ask whether pass partitioning changes the actual flow pattern. The example’s equal capacity rates are deliberate simplifying inputs, not properties of a real process.

Use the processing-tank page as an enquiry context, with the utility drawing attached. This guide tests temperature pairing. It does not promise that any exchanger can achieve the illustrative program; available area, transfer coefficients and pressure-drop limits still govern the design.

Which flow arrangement defines the hot/cold terminal-temperature comparison?

This blank worksheet is for your own project. It contains no H M machine trial result.

Customer Questions

Related Equipment References

Review the actual offered equipment and application separately from this educational example.

• processing-tank page

Primary References

These references support the technical principles discussed in this guide. The worked examples and review questions are educational.

• Alfa Laval’s plate-exchanger theory
• processing-tank page