Hostname: page-component-586b7cd67f-r5fsc Total loading time: 0 Render date: 2024-11-22T11:08:58.608Z Has data issue: false hasContentIssue false

Unsteady aerodynamics computation and investigation of magnus effect on computed trajectory of spinning projectile from subsonic to supersonic speeds

Published online by Cambridge University Press:  02 August 2019

F.A. Chughtai*
Affiliation:
Department of Mechanical & Aerospace Engineering, Institute of Avionics & Aeronautics, Air University, Islamabad, Pakistan
J. Masud
Affiliation:
Department of Mechanical & Aerospace Engineering, Institute of Avionics & Aeronautics, Air University, Islamabad, Pakistan
S. Akhtar
Affiliation:
School of Engineering Technology, National University of Technology, Islamabad, Pakistan

Abstract

This paper describes the extensive numerical investigation carried out on a 203-mm spin-stabilised projectile to study the effects of Magnus force at high angles of attack on the stability and flight-trajectory parameters, for further validation and incorporation in a 6-DOF trajectory solver for flight-stability analysis. Magnus force typically influences the course of flight by causing the projectile to drift from its intended path in addition to generation of inbuilt dynamic instabilities in pitch and yaw orientation and is a function of AoA and spin rate. This study is a consolidation of the authors’ previous research on the same caliber projectile but with time-accurate analysis. It has been found that typically, the Magnus force and moment calculation requires time-accurate Navier Stokes equations to be solved numerically for accurate prediction(1,2). Hence, to complete the extraction of static and dynamic coefficients derivatives, unstructured time-accurate CFD analysis on multiple configurations, ranging from subsonic to supersonic Mach regimes, has been evaluated using Large Eddy Simulation (LES) and found to be suitable for capturing the desired effects. However, the LES simulation requires non-dimensional wall distance (y+) of the order of 0.5 – 1, with LES_IQ > 75% thus, is computationally-intensive. In addition, to cover the entire flight envelope from Charge 1 (249 m/s) to Charge 7 (595 m/s), at spin rate from 500 rad/s to 750 rad/s, 30 cases have been evaluated to generate the time-accurate coefficient library for integration with 6-DOF solver analysis. The results obtained have been compared with the available experimental data and found to be in reasonable agreement. The results of 6-DOF solver, incorporating the extracted coefficients, were compared with firing-table results, which further validated the computational methodology. This study provides an insight on how opposite flow interacts with the attached boundary layer due to spin rate and generates a turbulent interacting flow with variation in vortical structures for Q-Criterion vortex-flow visualization.

Type
Research Article
Copyright
© Royal Aeronautical Society 2019 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Silton, S.I. Navier-stokes predictions of aerodynamic coefficients and dynamic derivatives of a 0.50-cal projectile, 29th AIAA Applied Aerodynamics Conference, Honolulu, Hawaii, 27–30 June 2011.Google Scholar
Despirito, J. and Heavey, K.R. CFD computation of magnus moment and roll damping moment of a spinning projectile, AIAA Atmospheric Flight Mechanics Conference and Exhibit, Providence, RI, 16–19 August 2004.Google Scholar
Jehmey, C. Wind tunnel test on the static aerodynamics of a spinning 106mm artillery shell model, Technical Report WSRL-0090-TR, 1979, Defense Research Center Salisbury, South Australia.Google Scholar
Miller, M.C. Wind tunnel measurements of the magnus induced surface pressures on a spinning artillery projectile model in the transonic speed regime, CRDEC-TR-86081, 1986, Chemical Research Development and Engineering Center.Google Scholar
Murphy, C.H. Free flight motion of symmetric missiles, AD442757, 1963, Ballistic Research Laboratories.Google Scholar
Mccoy, R.L. Aerodynamic and flight dynamic characteristics of the new family of 5.56 mm NATO ammunition, BRL-MR-3476, 1985, US Army Ballistic Research Laboratory.Google Scholar
Lieske, R.S. Use of the magnus force in the modified point mass trajectory model, BRL-MR-3870, 1990, U.S. Army Ballistic Research Laboratory.Google Scholar
Dickinson, E.R. The Zero-Yaw drag coefficient for projectile, 8-Inch: HE, M106, BRLM-1681, 1965, US Army Ballistic Research Laboratory.Google Scholar
Hitchcock, H.P. Aerodynamic data for spinning projectiles, Report No. 620, 1947, US Army Ballistic Research Laboratory.Google Scholar
Baranowski, L. Numerical testing of flight stability of spin-stabilised artillery projectiles, J Theoretical and Applied Mechanics 2013, 51 (2), pp 375385.Google Scholar
Khalil, M., Abdalla, H. and Kamal, O. Dispersion analysis for spinning artillery projectile, 13th International Conference on Aerospace Sciences & Aviation Technology, ASAT-13, May 26–28, 2009.CrossRefGoogle Scholar
Sahu, J. Virtual fly-out simulations of a spinning projectile from subsonic to supersonic speeds, 29th AIAA Applied Aerodynamics Conference, Honolulu, Hawaii, 27–30 June 2011.Google Scholar
Sahu, J. Computations of unsteady aerodynamics of a spinning body at transonic speeds, 27th AIAA Applied Aerodynamics Conference, San Antonio, Texas, 22–25 June 2009.CrossRefGoogle Scholar
Klatt, D., Hruschka, R. and Leopold, F. Investigation of the magnus effect of a generic projectile at Mach 3 up to 16 degrees angle of attack, J Applied Mechanics, 2013, 80, 031603. doi: 10.1115/1.4023434.CrossRefGoogle Scholar
Chughtai, F.A., Masud, J. and Akhtar, S. Aerodynamic data generation and 6 DOF trajectory calculation of a baseline large-caliber spinning projectile, AIAA Atmospheric Flight Mechanics Conference AIAA 2016–0784, San Diego, California, USA, 4–8 January 2016, AIAA SciTech.Google Scholar
Belaidouni, H., Zivkovic, S. and Samardzic, M. Numerical simulation in obtaining drag reduction for projectile with base bleed, Scientific Technical Review, 2016, 66 (2), pp 3642. doi: 10.5937/STR1602036B.CrossRefGoogle Scholar
Chughtai, F.A., Masud, J., Akhtar, S. Effect of Design Modifications on Computed Trajectory of a Large-Caliber Spinning Projectile, AIAA Atmospheric Flight Mechanics Conference AIAA 2016–0785, 4–8 January 2016, San Diego, California, USA, AIAA SciTech.Google Scholar
Celik, I.B., Cehreli, Z.N. and Yavuz, I. Index of resolution quality for large eddy simulations, ASME J Fluids Engineering, 2005, 127, pp 949958. doi: 10.1115/1.1990201.CrossRefGoogle Scholar
Sève, F., Theodoulis, S., Wernert, P., Zasadzinski, M., Boutayeb, M. Flight Dynamics Modeling of Dual-Spin Guided Projectiles, IEEE Transactions on Aerospace and Electronic Systems, September 10, 2016.Google Scholar
Wessam, M.E. Flow field investigations and aerodynamic characteristics of artillery projectile, International Conference of Electrical, Automation and Mechanical Engineering (EAME 2015).CrossRefGoogle Scholar