Shell And Tube Heat Transfer Coefficient. Amount of heat required heat flux wm2 ie thermal power per unit area q ddot. What is the overall heat transfer coefficient based on.
A shell and tube type heat exchanger is used to heat a non viscous process fluid from 30c to 55c. They are tube inside liquid media film coefficient shell side heating media film coefficient and metal wall resistance. U the overall heat transfer coefficient kjh m2 oc btuh ft2 ºf a heat transfer area m2 ft2 δt lm log mean temperature difference oc ºf c pt liquid specific heat tube side c ps liquid specific heat shell side kjkg ºk btulb ºf.
Examples of overall heat transfer coefficients shell and tube exchangers u wm2 c u btuhr ft2 f single phase gas gas low pressure 1 bar 5 35 1 6 gas gas high pressure 250 bar 150 500 25 90 gas liquid low pressure 15 70 3 15 gas liquid high pressure 200 400 35 70 liquid liquid 150 1200 25 210.
Most generally this is done using although in practice it is more common to assume that fluid properties can be treated as constant at the bulk average values and approximate the design equation with. U wm 2 c heat exchangers. 1 1 u o a o a i h i a o ln d o d i 2 π kl 1 h o where d i and d o are inner and outer diameters of the tube respectively. What is the overall heat transfer coefficient based on.