Abstract
The main goal of this study is to investigate the evaporation process of a coolant (water droplets) which is injected through spray nozzles mounted on a steam turbine bypass pipeline in a co-generator system. The study includes several important factors: (1) the effects of elbows on the flow pattern and evaporation process of the water particles; (2) heat transfer that affects the steam temperature and also the evaporation rates; and (3) the effects of insertion of a perforated plate in the flow path on the evaporation process.
Modeling of the high-pressure turbulent steam flow was based on a non-staggered finite volume method in 3-D, turbulent, compressible, two-phase dispersed flow formulations. Computations were performed by separating the entire pipeline system into four sections, each of which was generated in a 3-D grid system for more efficient computations by maintaining a sufficiently large number of meshes for each section. Flow calculations were made in each region separately by patching the end conditions from one pipe to the inlet conditions of the next one.
Through this research, numerous data have been acquired and analyzed for heat transfer mechanisms of the cooling water droplets in the pipeline system. The accuracy of the computations were validated by comparing them with theoretical models, and were shown to be quite reliable.