How do you detect fouling in a heat exchanger?

How do you detect fouling in a heat exchanger?

The off-line and on-line methods are build up by dividing the heat exchanger into sections. The states (temperatures) in the sections are represented with physical equations and the Kalman filter is used to estimate the states. Fouling detection is done by monitoring parameters of the model.

How does fouling factors affect heat transfer?

The deposition of any undesired material on heat transfer surfaces is called fouling. Fouling increases the overall thermal resistance and lowers the overall heat transfer coefficient of heat exchangers. Fouling also impedes fluid flow, accelerates corrosion and increases pressure drop across heat exchangers.

What is meant by fouling?

Fouling is the accumulation of unwanted material on solid surfaces. Fouling is usually distinguished from other surface-growth phenomena in that it occurs on a surface of a component, system, or plant performing a defined and useful function and that the fouling process impedes or interferes with this function.

How do you stop fouling?

The best way to avoid particulate fouling is to keep the cooling water clean and thereby prevent particles from entering the heat exchanger. However, in all cooling systems, and especially when using open cooling systems (with cooling towers), there will always be particles present in the cooling water.

What is fouling in pipes?

Fouling stands in technical applications, for the unwanted growth or formation of deposits on surfaces. Fouling occurs on the inside of pipes, machines or heat exchangers. These deposits reduce the cross-section of the pipe and thus impede the flow and heat transfer.

How do you find the fouling factor?

Typical Fouling Factors

1. Alcohol vapors : Rd = 0.00009 (m2K/W)
2. Boiler feed water, treated above 325 K : Rd = 0.0002 (m2K/W)
3. Fuel oil : Rd = 0.0009 (m2K/W)
4. Industrial air : Rd = 0.0004 (m2K/W)
5. Quenching oil : Rd = 0.0007 (m2K/W)
6. Refrigerating liquid : Rd = 0.0002 (m2K/W)
7. Seawater below 325 K : Rd = 0.00009 (m2K/W)

What is Microfouling?

The first, usually known as microfouling (attachment of microorganisms mainly bacteria and algal cells), involves the adsorption of dissolved organic molecules; those molecules provide nutrients for attaching the primary colonizers.

Which type of heat exchanger has more heat transfer for the same area?

Each of the three types of heat exchangers (Parallel, Cross and Counter Flow) has advantages and disadvantages. But of the three, the counter flow heat exchanger design is the most efficient when comparing heat transfer rate per unit surface area.

Which of the following is not associated with heat exchanger?

Which of the following is not associated with a heat exchanger? Explanation: The correction factor i.e. Mc Adam’s is associated with laminar film condensation on a vertical plate.

Which of the following is not an indirect contact type heat exchanger?

Which of the following is not an Indirect Contact type heat exchanger? Explanation: Spray and Tray type is a Direct Contact Type heat exchanger which involves the transfer of heat between two immiscible fluids by bringing them into contact at different temperatures.

Which is not true for shell and tube heat exchanger?

Shell and Tube Heat Exchangers are not commonly used in industries because of their inability to handle high pressure and temperature.

Which law of thermodynamics is related to the direction of heat transfer?

Many processes occur spontaneously in one direction only, and the second law of thermodynamics deals with the direction taken by spontaneous processes. According to the second law of thermodynamics, it is impossible for any process to have heat transfer from a cooler to a hotter object as its sole result.