Implementation of baffles is decided on the basis of size, cost and their ability to lend support to the tube bundles and direct flow:

• Longitudinal Flow Baffles (used in a two-pass shell)
• Impingement Baffles (used for protecting bundle when entrance velocity is high)
• Orifice Baffles
• Single segmental
• Double segmental
• Support/Blanking baffles
• Deresonating (detuning) baffles used to reduce tube vibration

Use of Baffle

The main roles of a baffle in a shell and tube heat exchanger are to:

• Hold tubes in position (preventing sagging), both in production and operation
• Prevent the effects of steam starvation, which is increased with both fluid velocity and the length of the exchanger
• Direct shell-side fluid flow along tube field. This increases fluid velocity and the effective heat transfer co-efficient of the exchanger

In a static mixer, baffles are used to minimize the tangential component of velocity which causes vortex formation, and thus promotes mixing.

In a chemical reactor, baffles are often attached to the interior walls to promote mixing and thus increase heat transfer and possibly chemical reaction rates.

In a household stoves like Handölkassetten and similar stoves a baffle is used to prevent the gas from going directly up in the chimney and possibly causing a chimney fire and direct the gas towards the front of the oven before it continues upwards into the chimney. In this case the baffle helps increase the efficiency of the stove as more heat leaves the gas before it exits.

• The baffles prevent the rotational flow without affecting radial or longitudinal flow. The tank is provided with baffles which prevent swirling and vortex formation. Except in very large tanks, four baffles are placed.