ABSTRACT
Two-phase flow investigations with special interest on the heat transfer behaviour are conducted on horizontal evaporator tubes in the diameter range between 50 and 85 mm. In view of the fact that future application of such horizontal tubes will be steam generation in the absorber tubes of parabolic troughs in solar power plants, the tubes are electrically heated on half the circumference alternately underneath or from the side. Heat fluxes up to 75 kW/m2 - related to the inner wall of the tube - are realized. The effect of different types of injection nozzles is analyzed as well as the influence of different amounts and various conditions of the injected water itself. The pressure range is varied between 30 and 100 bar, and the mass flux between 50 and 500 kg/m2 s.
