CFD-based design and simulation of hydrocarbon ejector for cooling

Highlights: • Designing high-performance hydrocarbon ejectors for cooling in hot climate regions. • Axisymmetric CFD simulation of ejector with NIST real gas thermophysical properties. • Pentane ejector having a linear relation between its expansion ratio and compression ratio. • Ejector with converging-area chamber performing better than ejector with constant-area section. • Pareto Frontier performance curves recommended for future hydrocarbon ejector cooling applications. -- Abstract: Ejector cooling with hydrocarbon as alternative refrigerant promises great application potential in hot climate regions. In order to unleash the potential of these sustainable cooling systems, it is essential to design high-performance hydrocarbon ejectors. In this paper, a computational fluid dynamic (CFD) simulation approach is proposed for detailed ejector modeling. The NIST real gas model is used to incorporate thermophysical properties of actual refrigerants for accurate ejector performance prediction. A hydrocarbon ejector performance is analyzed according to different operating and geometric conditions, where a linear relationship between the expansion ratio and the compression ratio is obtained for Pentane with an accuracy of 0.5%. A set of Pareto Frontier performance curves are also recommended for designing and operating energy-efficient hydrocarbon ejector cooling systems. Our results show that a small area ratio leads to a high ejector compression ratio, which is desired in hot climate applications. The other geometric design parameters have minor effects on the ejector performance. This work also indicates that ejectors with a converging-area chamber can achieve better overall performance compared to conventional ejectors.