Developing a New Algorithm to Design Thermo-Vapor Compressors Using Dimensionless Parameters: A CFD Approach

This paper aims to propose a new algorithm for designing thermal vapor compressors (TVCs) using given operation parameters. First, an axisymmetric model was used to simulate a TVC, and the results were compared with those from published experimental results. A simulation set was designed to analyze the TVC dimensions, and then statistically-significant parameters (p-value < 0.05) were chosen for the subsequent studies. Thereafter, three parametric lengths were defined and a model presenting entrainment ratio (ER) was developed using a set of simulation results. The obtained characteristic equation allows us to scale (up or down) the TVC to different capacities, calculate the real-time sizes or predict the performance. It was found that the critical "TVC/primary nozzle" throat diameter ratio is constant in every scale-up study, depending on operation conditions. By establishing a characteristic graph, the approach was expanded for a broader algorithm. The comparative results revealed that this approach is able to predict the ER for every scaling study with an error of less than 2.8%. This approach can be used to devise TVCs ejectors using any given ER and capacity within the ranges of possible usage.