Showing 3 results for Missile
A. R. Pishehvar and H. Ahmadi Kia,
Volume 20, Issue 2 (4-2001)
Abstract
In this study, the missile staging process by implementing a side-injected jet is simulated numerically. The problem is considered to be axisymmetric and the thin shear layer approximation of Navier-Stokes equations along with an algebraic turbulence model is used in a quasi-static form for the calculations. The free stream corresponds to a very high altitude flight condition with a Mach number of 10 and an injected jet pressure ratio of about 63000. An explicit Godunov-type scheme is used in the calculations, which is second-order in time and space. Computations are performed on the attached and separated geometry for a range of distances between the body and the warhead. The intense interactions between the jet flow and the main free-stream and its overall influences on the warhead aerodynamic loading are finally demonstrated.
Keywords: Missile Staging, Jet Interaction flow, TVD Scheme, Riemann problem
M. R. Soltani, H. Fazeli, B. Farahanieh and A. R. Davari,
Volume 21, Issue 1 (7-2002)
Abstract
An extensive experimental investigation to understand the aerodynamic behavior of wrap around fin (WAF) missile configuration has been conducted. Various tests using at first a standard model (TTCP) in the trisonic wind tunnel of Imam Hossein University has been performed. The tunnel has attest section of 60×60 cm2 and can operate at Mach numbers of 0.4≤M∞≤2.2 and at attack angles of -4˚≤α≤10˚. Experimental longitudinal results are compared with those of NASA and an engineering code. The results for TTCP model are in good agreement. After gaining confidence on the TTCP results, a new model of WAF rocket was designed, built and tested. This paper compares the results of two models tested under the same conditions.
Keywords: Wind tunnel, Wrap around fin, Missile, Balance WAF-TTCP
S. Nasrollahi Boroujeni, M. Fathi, A. Ashrafifar,
Volume 35, Issue 1 (9-2016)
Abstract
In this paper, a robust control law is proposed, based on Lyapunov’s theory and sliding mode control theory, in
order to track the angle of attack in nonlinear longitudinal dynamics of a missile. It is assumed that there are unmatched
uncertainties in the nonlinear systems. In the proposed algorithm, the controller gains are optimized by Particle Swarm
Optimization (PSO) algorithm. For this purpose, a cost function is extracted from the output tracking error. Simulation results
show that the proposed algorithm has better performance than conventional Proportional-Integral-Derivative (PID) controller in
the presence of unmatched uncertainties.
