Engineering ToolBox - Resources, Tools and Basic Information for Engineering and Design of Technical Applications!

Heat Exchangers - Fouling and Reduced Heat Transfer

Heat-transfer in heat exchangers are reduced by fouling.

Sponsored Links

During operation with liquids and gases a dirt film may build up on the heat exchanger surfaces . The deposit film is referred to as fouling

Increased thermal resistance caused by the deposit can normally only be obtained from tests or experience. The fouling factor can be determined as

Rd = 1 / Ud - 1 / U                            (1)


Rd = fouling factor - or unit thermal resistance of deposit (m2K/W)

Ud = overall heat transfer coefficient of heat exchanger after fouling (W/m2K)

U = overall heat transfer coefficient of clean heat exchanger (W/m2K)

(1) can also be expressed as:

Ud  = 1 / (Rd + 1 / U)

Typical Fouling Factors

  • Alcohol vapors : Rd = 0.00009 (m2K/W)
  • Boiler feed water, treated above 325 K : Rd = 0.0002 (m2K/W)
  • Fuel oil : Rd = 0.0009 (m2K/W)
  • Industrial air : Rd = 0.0004 (m2K/W)
  • Quenching oil : Rd = 0.0007 (m2K/W)
  • Refrigerating liquid : Rd = 0.0002 (m2K/W)
  • Seawater below 325 K : Rd = 0.00009 (m2K/W)
  • Seawater above 325 K : Rd = 0.0002 (m2K/W)
  • Steam : Rd = 0.00009 (m2K/W)
Sponsored Links

Related Topics

Related Documents

Sponsored Links

Engineering ToolBox - SketchUp Extension - Online 3D modeling!

3D Engineering ToolBox Extension to SketchUp - add parametric components to your SketchUp model

Add standard and customized parametric components - like flange beams, lumbers, piping, stairs and more - to your Sketchup model with the Engineering ToolBox - SketchUp Extension - enabled for use with the amazing, fun and free SketchUp Make and SketchUp Pro .Add the Engineering ToolBox extension to your SketchUp from the SketchUp Pro Sketchup Extension Warehouse!

About the Engineering ToolBox!


We don't collect information from our users. Only emails and answers are saved in our archive. Cookies are only used in the browser to improve user experience.

Some of our calculators and applications let you save application data to your local computer. These applications will - due to browser restrictions - send data between your browser and our server. We don't save this data.

Google use cookies for serving our ads and handling visitor statistics. Please read Google Privacy & Terms for more information about how you can control adserving and the information collected.

AddThis use cookies for handling links to social media. Please read AddThis Privacy for more information.


This page can be cited as

  • Engineering ToolBox, (2010). Heat Exchangers - Fouling and Reduced Heat Transfer. [online] Available at: [Accessed Day Mo. Year].

Modify access date.

. .


3D Engineering ToolBox - draw and model technical applications! 2D Engineering ToolBox - create and share online diagram drawing templates! Engineering ToolBox Apps - mobile online and offline engineering applications!

Scientific Online Calculator

Scientific Calculator

3 10

Sponsored Links