Thesis
Development and analysis of a variable diameter synthetic jet actuator
Washington State University
Master of Science (MS), Washington State University
2015
Handle:
https://hdl.handle.net/2376/101225
Abstract
Synthetic jet actuators are characterized by providing net momentum flux into a system with zero net mass injection. These actuators are used to improve performance in applications such as heat transfer and flow control. A unique application of synthetic jets is known as a variable diameter actuator. It is theorized the performance in such areas could be further increased by varying the diameter of the aperture in-phase with the actuator. A 16 vane camera aperture is placed at the end of a 15 cm long tube which is 3.18 cm in diameter. The aperture can vary its diameter from 36mm to 4 mm via a pneumatic cylinder. A second pneumatic cylinder actuates a piston within the tube to control the working fluid. Timing of the test rig is set up such that the aperture closes from as the piston travels out and opens as the piston retracts. The system is operational at frequencies of up to 5 Hz with air as the working fluid and up to 0.5 Hz with water as the working fluid. Using laser Particle Image Velocimetry (PIV) the flow and velocity fields are investigated. It is shown that flow structures resemble a hybrid of the fixed open and fixed closed cases with an initial slug of fluid followed by a short trailing jet. It is also seen that the vortex ring created by the operating aperture remains attached to the wall of the tank for a greater duration and appears to have greater circulation than other fixed diameter synthetic jets. In addition, the outstroke momentum flow of the operating aperture has a much higher peak, on the order of 75% larger, compared to fixed diameter synthetic jets. It is believed that this increase in circulation could lead to improved heat transfer performance. In addition, the higher momentum flow peak could lead to an increase in unsteady propulsion efficiency
Metrics
5 File views/ downloads
11 Record Views
Details
- Title
- Development and analysis of a variable diameter synthetic jet actuator
- Creators
- Spencer O'Callahan Albright
- Contributors
- Stephen A. Solovitz (Degree Supervisor)
- Awarding Institution
- Washington State University
- Academic Unit
- Electrical Engineering and Computer Science, School of
- Theses and Dissertations
- Master of Science (MS), Washington State University
- Publisher
- Washington State University; [Pullman, Washington] :
- Identifiers
- 99900525273301842
- Language
- English
- Resource Type
- Thesis