Theory And Experiment On Film Condensation Heat Transfer Outside Vertical Spiral Coil

Vertical spiral coil condenser has been widely concerned and applied because ofcompact structure and efficient performance. The key issue of its design and research isthe flowing of refrigerant on the surface of coils. Due to the complex structure,theoretical foundation about this condenser is weak. So a study for this theory is putforward in this paper.Since the vertical coil structure and heat transfer mechanism is similar tohorizontal bundle,the existing horizontal bundle calculation model can be used to solvethe problem of film condensation heat transfer outside vertical spiral coil. The first floorcoil is only affected by condensed condensate Expression of film thickness is proposedaccording to the force and energy balance of vertical spiral coil. The non-first floor isnot only affected by condensed condensate but also by falling condensate. Finally, theaverage conductivity of coils from the first floor to the last one is given through theexisting horizontal bundle calculation model and iterative approach.The correctness of the model is verified by bench. And experimental data iscontrolled and collected through LabVIEW. Finally the experimental data is stablewithin a certain range. The conductivity of film condensation is measured by the bench.Also the conductivity can be solved by model theory. The results show that there are9.7%errors between them. The model theory is proved to be correct.