Evaluating the performance of eductor as vacuum generator and condenser in thermal desalination
Year: 2025
Type: article
Abstract: This study explores three eductor nozzle configurations: single nozzle, multi-nozzle (three nozzles), and chevron nozzle (with varying teeth numbers). An experimental study was conducted on the single-nozzle-based eductor configuration, and the results were used to validate a numerical model developed in ANSYS Fluent 2024R1, which was then extended to analyze multi-nozzle and chevron designs. Key parameters such as vacuum generation capacity, the corresponding secondary flow saturation temperature, and the secondary flow rate were evaluated. Results reveal that the eductor with 10 teeth Chevron nozzle offers the highest vacuum generation capacity, achieving a minimum secondary flow saturation temperature of around 18°C at an inlet pressure of 230 kPa, outperforming the 4-teeth to 12-teeth configurations. The multi-nozzle eductor configuration with inter-nozzle distance-to-mixing chamber diameter (Dn/D) ratios of 0.23 achieved the highest vacuum generation capacity among all the multi-nozzle configurations studied. A case study integrating the eductor into a thermal vacuum desalination system highlights its potential to replace bulky vacuum pumps and condensers, enabling more compact desalination setups. All three eductor designs were analyzed, with the 10-tooth Chevron nozzle achieving a maximum secondary flow rate of 20kg/hr and a minimum secondary flow saturation temperature of around 18°C. The multi-nozzle and Chevron nozzle configurations demonstrate enhanced vacuum generation, reduced saturation temperature of the secondary flow, and improved secondary flow rate compared to the single nozzle. These findings emphasize the role of nozzle design in optimizing eductor-driven thermal vacuum desalination (TVD) systems and suggest future research on two-phase flow dynamics for desalination applications.
Source: Applied Thermal Engineering
Institutions: RMIT University, University of Pennsylvania
Language: English
Subfield: Mechanical Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $3,660
OpenAlex ID: W7077047136