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The paper describes small-capacity irrigation evaporators that improve the performance of a refrigeration unit, as they exclude the release of liquid freon into the compressor suction pipe under sharp increasing of heat load or during ship rolling. The relevance of studying heat transfer at freons boiling in a moving film has been proved. The results and analysis of experimental data on average heat transfer coefficients are presented. The graph shows the dependence of the average heat transfer coefficients on the heat flux density at various irrigation densities. There are presented the results of special experiments determining the effect of irrigation density on heat transfer. It has been stated that the effect of pressure or saturation temperature in the modes of evaporation and developed boiling manifests itself in different ways. With developed boiling, the beam pitch does not have a significant effect on heat transfer. The experiments were carried out on two stands: small-row and multi-row. The pipes were heated with an internal electric heater. It has been inferred that heat transfer in the film is more intense than in volume, therefore, smooth steel pipes can be used in irrigation evaporators instead of finned copper tubes, which are used in flooded devices. The boiling process in a film can be described by equations valid for a large volume, taking into account quantitative differences. The values of a constant coefficient and the criteria exponents are given; the similarity equation for the regime of developed bubble boiling of freons is derived. The calculated dependencies can be applied in evaluating the operation of irrigation evaporators of ship refrigeration units.

The object of research includes the experimental evaporator, the model of a large Freon refrigeration plant, and technical-grade Freon R22. The purpose of the research is to assess the effect of the tube bank lane and regime parameters (saturation pressure and saturation temperature) on heat transfer during technical-grade Freon boiling in multi-row tube banks, as well as to continue studying the features of freon boiling processes in the evaporators of large refrigerating machines. The article shows the calculated dependences of the influence of regime parameters on heat transfer in the process of boiling Freon R12 and R22 in flooded evaporators with great height of experimental tube bank. The visual observations of the boiling process have been described. Calculated dependences of heat transfer along the tubes in the tube bank have been obtained, the character of heat transfer changes and temperature distribution according to the height of the tube bank has been defined.