Advances in Ejector Technology - A Tribute to Hans von Ohain's Vision
Abstract
A great deal of fundamental investigations and applied research has been performed in the area of ejectors as jet pumps over a period of several decades. However, it is only recently that ejectors are recognized as thrust augmentors since the early work of Von Karman. Subsequently, U. S. Air Force undertook a project of developing the ejector technology for thrust augmentation purposes. A great deal of fundamental and applied work was performed in the course of the last fifteen to twenty years, and a considerable amount of the results has been published. Following are some of the significant and fundamental developments in thrust augmenting ejectors that resulted from ARL's studies: (1) Development of hypermixing nozzles for mixing enhancement was achieved; (2) Demonstration that mixing and diffusion of flows could be done simultaneously with performance advantage was accomplished; (3) An incompressible ejector analysis which will parametrically evaluate an ejector performance was performed; (4) Thrust augmentation of the order of two in an ejector of inlet area ratio 23 was successfully achieved experimentally; (5) Good thrust augmentation for V/STOL purposes was also realized by using full- scale multichannel ejectors. (6) It was demonstrated that diffusion normal to the plane of the velocity profile always leads to improved mixing in contrast to diffusion in the plane of the velocity profile; (7) An ejector-wing model was designed, fabricated and tested; and (8) Further compactness of the ejector was realized by the utilization of a device that combines efficient boundary-layer energization with a configured diffusion device, that is, trapped vortex cavity.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1982
- Accession Number
- ADP000337
Entities
People
- K. S. Nagaraja
Organizations
- Wright Laboratory