Open AccessCOMPUTATIONAL STUDY OF THE EFFECT OF GEOMETRIC PARAMETERS ON THE PERFORMANCE OF SINGLE EXPANSION RAMP NOZZLE FLOWS
Author(s) -
Suresh Chandra Khandai,
Ashwin Kumar K,
K. M. Parammasivam
Publication year - 2014
Publication title -
international journal of mechanical and industrial engineering
Language(s) - English
Resource type - Journals
ISSN - 2231-6477
DOI - 10.47893/ijmie.2014.1170
Subject(s) - nozzle , mach number , thrust , mechanics , rotational symmetry , computational fluid dynamics , grid , supersonic speed , geometry , structural engineering , materials science , physics , mathematics , engineering , mechanical engineering
The present work deals with the computational study of the single expansion ramp nozzle (SERN) flows for the supersonic regime. Theoretical calculations are carried out for different geometries with certain assumptions. Based on the initial calculation and with the help of Method of Characteristics, nozzle configuration with similar axisymmetric convergent portion and distinct non-axisymmetric divergent portions are drafted. Commercial CFD software ANSYS 12 with Navier Stokes code is used for the computational studies. The study begins with a simple upper flat ramp at different angles with a very small lower cowl at fixed angles. The divergent section of a conventional three-dimensional nozzle is used as the upper ramp of the SERN. The study includes the variation of the ramp at different angles ranging from 16 deg. to 24 deg. with 2 deg. intervals, the cowl angle ranging from 0 deg. to 6 deg. with 2 deg. intervals and the length of the cowl varying from 0.2, 0.4, 0.6, 0.8 and 1.0 times the length of the ramp. The performance parameters like Thrust, Normal force and Mach Variation for these different contours are analyzed and compared. The various parameters used are nozzle length, cowl length, cowl angle, ramp-angle, and ramp length. The shape of the SERN is optimized for the design parameters. The grid sensitivity computational analysis is also performed before finalizing the grid for study.