Abstract
A self-seeding particle method is proposed for particle image velocimetry measurements in closed cycles such as Organic Rankine Cycles. Condensed droplets of vapor are used as tracers in a closed cycle for both subsonic and supersonic regimes. A free jet of R245fa in the vapor phase is examined in a case study with two different nozzle pressure ratios of 5.1 and 2.1 to evaluate the tracer particles in both supersonic and subsonic conditions. A simple turbulent jet in subsonic conditions and an under-expanded jet are observed in high supersonic conditions. The flow structures of the under-expanded jet are captured using the proposed method, and vivid images of the Mach disk and shock cells are obtained. A series of Schlieren photography experiments are performed to validate the proposed method. The results show that the method can be a good candidate for tracer particles in the closed cycles where condensation of the working fluid is possible.
Highlights
A self-seeding particle method is proposed for particle image velocimetry measurements in closed cycles such as Organic Rankine Cycles
There have been a couple of attempts for measuring the flow characteristics of this flow but they have remained on the design step or point measurement such as TU Delft[8,9], Politecnico de Milano[10] and by White and S ayma[11] where a closed-loop of organic vapors was designed
The Particle Image Velocimetry (PIV) flow structures are the same as Schlieren photography which can prove the effectiveness of the proposed method with its uncertainties
Summary
To study the feasibility of the method, a jet flow of R245fa was considered in the closed c ycle[23]. This method could be applied to other vapors where condensation is possible. As in this modified version, the ray path from LS to the camera is shorter than the conventional type, the image quality is higher A Phantom high-speed camera is used to capture the images
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
