Condensers design method

Film-type condensation is more common and more dependable. Dropwise condensation normally needs to be promoted by introducing an impurity into the vapor stream. Substantially higher (6 to 18 times) coefficients are obtained for dropwise condensation of steam, but design methods are not available. Therefore, the development of equations for condensation will be for the film type only. 

Cooler Condenser Design Lb-Water Program No. 710402 Water Rate Tube Modified Colbiu-n-Hougen, Bras Method Design Calc, for Sec. Coolers—Water Sat d at 110°F TL-in. Cooling Water Pass No. 2 In. °F 48.00 Lb-Gas, Gas Rate HLI, Water 8c Tube Acc-F, Program Tube 92.30 lb hr tube 480.00 Overall Coeff. Accmacy. 10 I.D. Controlled to 0.1 F Pl-Atm, Press, of Sys Gas in Top I.OOO ... 

The following features, common to all these situations, must be considered in the developing design methods for mixed vapour condensers ... 

Empirical methods approximate methods, in which the resistance to heat transfer is considered to control the rate of condensation, and the mass transfer resistance is neglected. Design methods have been published by Silver (1947), Bell and Ghaly... 

As a rough guide, the following rules of thumb suggested by Frank (1978) can be used to decide the design method to use for a partial condenser (cooler-condenser) ... 

Bell, K. J. andGHALY, M. A. (1973) Chem. Eng. Prog. Symp. Ser. No. 131, 69,72. An approximate generalized design method for multicomponent/partial condensers. 

McNaught, J. M. (1983) An assessment of design methods for condensation of vapors from a noncondensing gas, in Heat Exchangers Theory and Practice (McGraw-Hill). 

There are several other methods which have been used in the experimental determination of electron impact ionization cross sections. Nottingham and Bell76,77 developed a method specifically for the purpose of accurately determining the absolute electron impact ionization cross section of mercury. A semicircular electron velocity analyzer included in their design ensured that very high energy resolution was possible since only electrons of the required velocity emerged from the analyzer into the ionization chamber. Other aspects of the experiment are similar to the condenser plate method. 

Thonon B, Chopard F. Condensation in plate heat exchangers assessment of a general design method. Eurotherm 47, Heat Transfer in Condensation. Elsevier, 1996 10-18. 

Bell, K. J. and Ghaly, M. A., An Approximate Generalized Design Method for Multicomponent/Partial Condensers, AIChE Symp. Ser., 69, 72-79 (1972). 

---