Study of the Effect of Over-expansion Factor on the Flow Transition in Dual Bell Nozzles

Dual bell nozzle is a promising one among the altitude adaptation nozzle concepts, which offer increased nozzle performance in rocket engines. Its advantage is the simplicity it offers due to the absence of any additional mechanical device or movable parts. Hence it offers reliability along with improved nozzle performance as demanded by future launch vehicles. Among other issues, the flow transition to the extension nozzle of a dual bell nozzle is one of the major issues being studied in the development of dual bell nozzle. A parameter named over-expansion factor, which controls the value of the wall inflection angle, has been reported to have substantial influence in this transition process. This paper studies, through CFD and cold flow experiments, the effect of overexpansion factor on flow transition in dual bell nozzles.




References:
[1] Hagemann, G., Immich, H., Nguyen, T. V., and Dumnov, G. E.,
"Advanced Rocket Nozzles," Journal of Propulsion and Power, Vol. 14,
No. 5, September-October 1998 pp. 620-634
[2] Genin, C., and Stark, R., "Experimental Study on Flow Transition in
Dual Bell Nozzles," Proceedings of the 45th AIAA/ASME/SAE/ASEE
JPC and Exhibit, August 2009, Denver, Colorado. AIAA 2009-4855.
[3] Bijukumar K. S., Mathew George, Baiju A. P., Balachandran P.,
Rajamanohar and N. K. Gupta, "Development of Dual Bell Nozzle for
Future Launch Vehicles," Proceedings of IISc Centenary Conference &
Exhibition on Aerospace Engineering 2009,May 2009, Bangalore, India.
[4] Tomita, T., Takahashi, M., and Sasaki, M., "Investigation on
Characteristics of Conventional-Nozzle-Based Altitude Compensating
Nozzles by Cold-flow Tests (II)-Side-Load Characteristics During
Transition," Proceedings of the 43rd AIAA/ASME/SAE/ASEE JPC and
Exhibit, July 2007, Cincinnati, OH. AIAA 2007-5472.
[5] Tomita, T., Takahashi, M., Sasaki, M., and Tamura, H., "Investigation
on Characteristics of Conventional-Nozzle-based Altitude Compensating
Nozzles by Cold-Flow Tests," Proceedings of the 42nd
AIAA/ASME/SAE/ASEE JPC and Exhibit, July 2006, Sacramento,
California. AIAA 2006-4375.
[6] Kimura, T., Niu, K., Yonezawa, K., Tsujimoto, Y., and Ishizaka, K.,
"Experimental and Analytical Study for Design of Dual Bell Nozzles,"
Proceedings of the 45th AIAA/ASME/SAE/ASEE JPC and Exhibit,
August 2009, Denver, Colarado. AIAA 2009-5149.
[7] Miyazawa, M., Takeuchi, S., Takahashi, M., "Flight Performance of
Dual-Bell Nozzles," AIAA 2002-0686
[8] Otsu, H., Miyazawa, M., Nagata, Y., "Design Criterion of the Dual-Bell
Nozzle Contour," IAC-05-C4.2.08.
[9] Nasuti, F., Onofri, M., and Martelli, E., "Role of wall shape on the
Transition in Dual-Bell Nozzles," 39th AIAA/ASME/SAE/ASEE JPC
and Exhibit, Jul. 2003, Huntsville, Alabama. AIAA 2003-4911