American Institute of Aeronautics and Astronautics 1 Theoretical and Experimental Modeling of Vortex Engine in Ramjet Application S. Besharat Shafiei 1 and A. Ghafourian 2 Sharif University of Technology, Tehran, Iran, 11365-8639 M. H. Saidi 3 Sharif University of Technology, Tehran, Tehran, 11365-8639, Iran and A. A. Mozafari 4 Sharif University of Technology, Tehran, Tehran, 11365-8639, Iran A new experimental facility was designed, fabricated and tested to model and study the possibility of applying the bidirectional swirl flow on the combustion chamber of airbreathing subsonic ramjet engine. Appropriate intake was designed to convert axial external air to tangential swirl flow inside the combustion chamber. Inlets with appropriate angles conduct the swirl flow into the chamber and create bidirectional swirl flow field in the combustion chamber. This flow field has been modeled theoretically to determine the velocity field characteristics by previous researchers. Bidirectional swirl flow in liquid fuel ramjet engines has the proven advantage of keeping the combustion chamber walls cool and in solid fuel ramjet engines increases the fuel burning rate as demonstrated in the previous investigations. The experimental study was performed by using propane and air as fuel and oxidizer, respectively. The temperature of combustion chamber wall was measured and found to be as low as 100 . The possibility of combining the airbreathing bidirectional swirl flow and ramjet engine was proved experimentally. The temperature variations at 3 points of the combustion chamber wall of this airbreathing bidirectional swirl flow engine were measured relative to time. The temperature variations on the same three points relative to various mass fuel air ratios were measured and are reported. Further development of this type of combustion chamber enables manufacturers to use less expensive and more available material in their production of combustors with improved combustion efficiency due to the increased mixing rate and cooled combustion chamber wall. Nomenclature l : Chamber aspect ratio L :Chamber length Fuel D :Inlet fuel pipe diameter . Air m :Air mass flow rate . fuel m :Fuel mass flow rate P :Chamber pressure 0 Q :Outlet volumetric flow rate i Q :Inlet volumetric flow rate R :radial coordinate 1 Graduate Student, Aerospace Engineering, besharat@alum.sharif.edu, AIAA Student Membership. 2 Professor, Aerospace Engineering, Ghafourian@sharif.edu, No membership. 3 Professor, Mechanical Engineering, Saman@sharif.edu, No Membership. 4 Professor, Mechanical Engineering, Mozafari@sharif.edu, No Membership. 45th AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit 2 - 5 August 2009, Denver, Colorado AIAA 2009-5433 Copyright © 2009 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved.