A heat exchanger is a device used to transfer heat between two or more fluids (liquids or gases) without them mixing. It’s widely used in engineering applications where heating or cooling is required, such as in power plants, chemical processing, refrigeration, and HVAC systems.
How It Works
Heat flows from the hotter fluid to the cooler one, typically through a solid barrier (usually metal) that separates the two fluids. The fluids may flow in the same direction (parallel flow), opposite directions (counterflow), or cross paths (crossflow).
Common Types of Heat Exchangers
| Type | Description |
| Shell and Tube | Consists of a series of tubes inside a cylindrical shell. One fluid flows through the tubes, and another flows around them. |
| Plate | Uses thin, corrugated plates stacked together. Fluids flow between alternate plates. Very efficient for compact designs. |
| Air-cooled | Uses air to remove heat from a fluid, common in car radiators. |
| Double Pipe | One pipe inside another; fluids flow in opposite directions for better efficiency. |
| Regenerative | The same surface alternately stores and transfers heat to incoming fluid. Used in gas turbines. |
Applications
- HVAC systems (heating, ventilation, air conditioning)
- Automotive (radiators, intercoolers)
- Power plants (steam condensers)
- Chemical industry (reactor cooling)
Food processing (pasteurization systems)