Dr Danie Els

Snr Lecturer : Design and Mechatronics Division

Dr Danie Els is currently a Senior Lecturer in the Design and Mechatronics Division. He did his MEng on the design and analysis of the dynamics of an impact fuze for a 40 mm high explosive grenade, and his PhD on the effectiveness of particle dampers under centrifugal loads. His fields of speciality are in mechanism design, optimisation, and granular dynamics.

Academic Qualifications

BEng (Mechanical), Pretoria, 1983
MEng (Mechanical) (Cum Laude), Stellenbosch, 1995
PhD (Mechanical Eng), University of Stellenbosch, 2009

Professional Experience

1996 - present:	University of Stellenbosch, Dept Mechanical and Mechatronics Engineering Snr Lecturer (Design and Mechatronics Division)
1994 - 1996:	Swartklip Products, Division of Denel Research and Development Engineer Design of a new mechanical impact fuze for 40mm grenade system. Work on self-destruct fuzes, automatic weapons and artillery systems.
1992 - 1994:	Houwteq, Division of Denel Research and Development Engineer Satellite orbit and constellation design. Satellite dynamics.
1989 - 1991:	Houwteq, Division of Denel Systems Engineer: Rocket Performance Predictions Responsible for performance software and performance database. Recalculations of rocket motor prediction models after test firings. Predictions of normal trajectories for flight tests. Data analysis.
1987 - 1988:	Swartklip Products, Division of Denel Research and Development Engineer Qualification and industrialisation of the 40mm grenade. Design and development of 155mm carrier shells and mortars. Work on internal, external ballistics software, test equipment and production tooling design.
1985 - 1986:	South African Defence Force (Technical Services Corps) Technical Officer: Lieutenant (National Service and Citizen Force) Completed Junior Leader's course (Infantry), Technical Officer's course and Workshop Officer's course (Captain's course)
1983 - 1986:	Armscor, Small Arms Division Research and Development Engineer Member of a team that did the design, development and qualification of a multi shot 40mm grenade launcher for the SADF Infantry.

Fields of Research

Granular Dynamics
Particle Dampers
Mechanisms

Fields of Interest

Mechanism Design (runaway escapements)
Infantry weapons and ammunition development
Design Optimisation

Publications, Presentations and Patents

2015

Proceedings International

MUIYSER J, ELS DNJ, VAN DER SPUY SJ, ZAPKE AJ. The determination of fan blade aerodynamic loading from a measured response. ASME Turbo Expo 2015, Montreal, Canada, The American society of Mechanical Engineers 2015: 1-12.

2014

Journal Articles (subsidised)

MUIYSER J, ELS DNJ, VAN DER SPUY SJ, ZAPKE A. Measurement of air flow and blade loading at a large-scale cooling system fan. R&D Journal 2014; 30 : 30-38.

VAN WYK G, ELS DNJ, AKDOGAN G, BRADSHAW SM, SACKS N. Discrete element simulation of tribological interactions in rock cutting. International Journal of Rock Mechanics and Mining Sciences 2014; 65 : 8-19.

Proceedings International

MUIYSER J, ELS DNJ, VAN DER SPUY SJ, ZAPKE A. Investigation of Large-Scale Cooling System Fan Blade Vibration. ASME Turbo Expo 2014: Turbine Technical Conference and Exposition, Düsseldorf, Germany, 2014: 1-13.

2013

Proceedings International

ELS DNJ. Damping of rotaing beams with particle dampers: Discrete element method analysis. Powders and Grains 2013, Sydney, Australia, AIP Publishing 2013: 867-870.2013

2012

Proceedings International

MUIYSER J, ELS DNJ, VAN DER SPUY SJ. Simultaneous measurement of air flow and blade loading conditions in an air-cooled steam condensor fan. FAN2012, Senlis, France, 2012: 12.

2011

Journal Articles (subsidised)

ELS DNJ. Damping of Rotating Beans with Particle Dampers: Experimental Analysis. AIAA Journal 2011; 49(10) : 2228-2238.

2010

Journal Articles

COETZEE CJ, ELS DNJ, DYMOND GFD. Discrete element parameter calibration and the modelling of dragline bucket filling. Journal of Terramechanics 2010; 47 : 33-44

Journal Papers

1.	Coetzee, C. J. and Els, D. N. J., Calibration of discrete element parameters and the modelling of silo discharge and bucket filling, Computers and Electronics in Agriculture, 65 (2): 198-212, 2009.
2.	Coetzee, C. J. and Els, D. N. J., Calibration of granular material parameters for DEM modelling and numerical verification by blade-granular material interaction, Journal of Terramechanics, 46 (1): 15-26, 2009.
3.	Coetzee, C. J. Els, D. N. J. and Dymond, G.F., Discrete element parameter calibration and the modelling of dragline bucket filling, Journal of Terramechanics, 2009, Doi: 10.1016/j.jterra.2009.03.003.

International Conference Proceedings

1.	Els, D. N. J., Damping of rotating beams with particle dampers, 50th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference, AIAA 2009-2688, PAlm Springs, California, 4-7 May 2009.
2.	Els, D. N. J., Pieterse, H. and De Bruin, M., New extended range shoulder-fired 40mm grenade system, 22nd Small Arms and Cannons Symposium DCMT, Shrivenham, UK, 19-21 Aug 2008.
3.	Coetzee, C, J, and Els, D. N. J., Modelling excavator bucket filling with DEM, Fifth World Congress on Computational Mechanics, Vienna, Austria, 7-12 Jul 2002.
4.	Els, D. N. J., Numerical analysis of the motion of a runaway escapement, ASME 2000 International Design Engineering Technical Conference, Baltimore, Maryland, USA, Sep 2000.
5.	Crouse, P. G. and Els, D. N. J., A rigid Multibody dynamical description of a rope and pully problem, SACAM 2000, Durban, South Africa, Jan 2000.
6.	Els, D. N. J. and Coetzee, C. J., Friction forces in a vertically pushed granular column, International Symposium on Reliable Flow of Particulate Solids III, Porsgrunn, Norway, Aug 1999.