Jump to content

Latest Downloads

Recent Status Updates

  • Photo
      11 Jun
    Ajay S. Satpute

    Hi, I have started my own engineering consultancy in India. Converge Engineering Pvt. Ltd. For more information, please visit www.converge.net.in

    Show comments (1)
View All Updates

Chemical and Process Engineering Resources

- - - - -

Category: Heat Transfer Technology
Question: Are there any good shortcuts for estimating overall heat transfer coefficients?
Keywords: shell,tube,heat,transfer,exchangers,overall,coefficients,relations,equations
Answer: In the preliminary design of shell and tube heat exchangers you need an estimate of the overall heat transfer coefficient (U). Process simulator programs give you a UA from which you can estimate the surface if you have a U value. An estimate can be made from the following: Rt = Fouling + Sqrt(avg tube viscosity)/150 +((avg shell viscosity) 0.27)/140U = 1/RtFouling is the total for both sides. The above is limited to a maximum viscosity of 3 cP for the tube side. There is no limit on the shell viscosity. This is also limited to bare tube surface with no turbulation devices. Source: Gulley Computer Associates