Search results

Filters

  • Journals

Search results

Number of results: 5
items per page: 25 50 75
Sort by:
Download PDF Download RIS Download Bibtex

Abstract

Abstract The reachability of standard and fractional-order continuous-time systems with constant inputs is addressed. Positive and non-positive continuous-time linear systems are considered. Necessary and sufficient conditions for the existence of such constant inputs that steers the system from zero initial conditions to the given final state in desired time are derived and proved. As an example of such systems the electrical circuits with DC voltage sources are presented.
Go to article

Authors and Affiliations

Krzysztof Rogowski
Download PDF Download RIS Download Bibtex

Abstract

The problem of optimal driving techniques during fuel economy competition is considered. The kinetic model of the record wheeled vehicle is proposed. It is regarded as a particle moving on a trace with variable slope angle. Engine characteristics are taken into account. The fuel consumption is minimized as the vehicle goes over a given distance. The problem is formulated in optimal control. The direct pseudospectral Chebyshev’s method is employed. The motion of student’s vehicle representing the Faculty of Power and Aeronautical Engineering during Shell Eco-marathon in Nogaro, France, in 2006, is used as an example.

Go to article

Authors and Affiliations

Krzysztof Rogowski
Ryszard Maroński
Download PDF Download RIS Download Bibtex

Abstract

The minimum-time problem for a glider flying in the vertical plane is considered. The glider is regarded as a particle moving in the atmosphere in given thermal conditions. The problem is formulated in optimal control and solved using direct pseudospectral Chebysev's method. The data are taken for the Word Class Glider PW-5 "Smyk". Computed optimum results are compared with glider's trajectories from the Second Domestic Glider Championship 2006, Suwałki, Poland.

Go to article

Authors and Affiliations

Krzysztof Rogowski
Ryszard Maroński
Download PDF Download RIS Download Bibtex

Abstract

Small-scale vertical-axis wind turbines can be used as a source of electricity in rural and urban environments. According to the authors’ knowledge, there are no validated simplified aerodynamic models of these wind turbines, therefore the use of more advanced techniques, such as for example the computational methods for fluid dynamics is justified. The paper contains performance analysis of the small-scale vertical-axis wind turbine with a large solidity. The averaged velocity field and the averaged static pressure distribution around the rotor have been also analyzed. All numerical results presented in this paper are obtained using the SST k-ω turbulence model. Computed power coefficients are in good agreement with the experimental results. A small change in the tip speed ratio significantly affects the velocity field. Obtained velocity fields can be further used as a base for simplified aerodynamic methods.

Go to article

Bibliography

[1] B.F. Blackwell. The vertical-axis wind turbine “How it works”. Energy Report, SLA-74-0160, Sandia Laboratories, 1974.
[2] K. Jankowski. Vertical axis turbine of Darrieus h-type with variable blade incidence angle concept design. M.Sc. Thesis, Warsaw University of Technology, Poland, 2009.
[3] I. Paraschivoiu. Wind Turbine Design: With Emphasis on Darrieus Concept. Polytechnic International Press, Canada, 2002.
[4] I. Paraschivoiu, O. Trifu, and Saeed F. H-Darrieus wind turbine with blade pitch control. International Journal of Rotating Machinery, 2009:ID 505343, 2009. doi: 10.1155/2009/505343.
[5] R. Bravo, S. Tullis, and S. Ziada. Performance testing of a small vertical-axis wind turbine. In Proceedings of the 21st Canadian Congress of Applied Mechanics CANCAM, Toronto, Canada, 7-9 June 2007.
[6] M.R. Islam, S. Mekhilef, and R. Saidur. Progress and recent trends of wind energy technology. Renewable and Sustainable Energy Reviews, 21:456–468, 2013. doi: 10.1016/j.rser.2013.01.007.
[7] F. Scheurich, T.M. Fletcher, and R.E. Brown. The influence of blade curvature and helical blade twist on the performance of a vertical-axis wind turbine. In 4 8th AIAA Aerospace Sciences Meeting Including the New Horizons Forum and Aerospace Exposition, Orlando, USA, 4-7 Jan. 2010. doi: 10.2514/6.2010-1579.
[8] H.A. Madsen, T.J. Larsen, U.S. Paulsen, and L. Vita. Implementation of the actuator cylinder flow model in the HAWC2 code for aeroelastic simulations on vertical axis wind turbines. In Proceedings of 51st AIAA Aerospace Sciences Meeting including the New Horizons Forum and Aerospace Exposition, Dallas, USA, 7-10 Jan. 2013. doi: 10.2514/6.2013-913.
[9] W. Tjiu, T. Marnoto, S. Mat, M.H. Ruslan, and K. Sopian. Darrieus vertical axis wind turbine for power generation II: Challenges in HAWT and the opportunity of multimegawatt Darrieus VAWT development. Renewable Energy, 75:560–571, March 2015. doi: 10.1016/j.renene.2014.10.039.
[10] M. Islam, D.S.K. Ting, and A. Fartaj. Aerodynamic models for Darrieus-type straight-bladed vertical axis wind turbines. Renewable and Sustainable Energy Reviews, 12(4):1087–1109, 2008. doi: 10.1016/j.rser.2006.10.023.
[11] M Abdul Akbar and V Mustafa. A new approach for optimization of vertical axis wind turbines. Journal of Wind Engineering and Industrial Aerodynamics, 153:34–45, 2016. doi: 10.1016/j.jweia.2016.03.006.
[12] J.H. Strickland, T. Smith, and K. Sun. A vortex model of the Darrieus turbine: An analytical and experimental study. Report SAND81-7017, Sandia National Laboratories, 1981.
[13] C.S. Ferreira, H.A. Madsen, M. Barone, B. Roscher, P. Deglaire, and I. Arduin. Comparison of aerodynamic models for vertical axis wind turbines. Journal of Physics: Conference Series, 524(1):012125, 2014. doi: 10.1088/1742-6596/524/1/012125.
[14] P. Lichota and D.A. Noreña. A priori model inclusion in the multisine maneuver design. In 17th International Carpathian Control Conference (ICCC), pages 440–445, Tatranska Lomnica, Slovakia, 29 May – 1 June 2016. doi: 10.1109/CarpathianCC.2016.7501138.
[15] A. Allet, S. Hallé, and I. Paraschivoiu. Numerical simulation of dynamic stall around an airfoil in Darrieus motion. Journal of Solar Energy Engineering, 121:69–76, 1999. 10.1115/1.2888145.
[16] C.S. Ferreira, H. Bijl, G. van Bussel, and G. van Kuik. Simulating dynamic stall in a 2D VAWT: modeling strategy, verification and validation with particle image velocimetry data. Journal of Physics: Conference Series, 75:012023, 2007. doi: 10.1088/1742-6596/75/1/012023.
[17] E. Amet, T. Maître, C. Pellone, and J.L. Achard. 2D numerical simulations of blade-vortex interaction in a Darrieus turbine. Journal of Fluids Engineering, 131(11):111103, 2009. doi: 10.1115/1.4000258.
[18] W.Z. Shen, J.H. Zhang, and J.N. Sørensen. The actuator surface model: a new Navier-Stokes based model for rotor computations. Journal of Solar Energy Engineering, 131(1):011002, 2009. doi: 10.1115/1.3027502.
[19] F. Schuerich and R.E. Brown. Effect of dynamic stall on the aerodynamics of vertical-axis wind turbines. AIAA Journal, 49(11):2511–2521, 2011. doi: 10.2514/1.J051060.
[20] A. Laneville and P. Vittecoq. Dynamic stall: the case of the vertical axis wind turbine. Journal of Solar Energy Engineering, 108(2):140–145, 1986. doi: 10.1115/1.3268081.
[21] M.C. Claessens. The Design and Testing of Airfoils for Application in Small Vertical Axis Wind Turbines. M.Sc. Thesis, Delft University of Technology, The Netherlands, 2006.
[22] P. Marsh, D. Ranmuthugala, I. Penesis, and G. Thomas. Three dimensional numerical simulations of a straight-bladed vertical axis tidal turbine. In 1 8th Australasian Fluid Mechanics Conference, Launceston, Australia, 3-7 December 2012.
[23] K. Rogowski. Analysis of Performance of the Darrieus Wind Turbines. Ph.D. Thesis, Warsaw University of Technology, Poland, 2014.
[24] K. Rogowski and R. Maronski. CFD computation of the Savonius rotor. Journal of Theoretical and Applied Mechanics, 53(1):37–45, 2015. doi: 10.15632/jtam-pl.53.1.37
[25] F.R. Menter. Two-equation eddy-viscosity turbulence models for engineering applications. AIAA Journal, 32(8):1598–1605, 1994. doi: 10.2514/3.12149.
[26] O. Guerri, A. Sakout, and K. Bouhadef. Simulations of the fluid flow around a rotating vertical axis wind turbine. Wind Engineering, 31(3):149–163, 2007. doi: 10.1260/030952407781998819.
[27] F. Scheurich, T.M. Fletcher, and R.E. Brown. Simulating the aerodynamic performance and wake dynamics of a vertical-axis wind turbine. Wind Energy, 14(2):159–177, 2011. doi: 10.1002/we.409.
Go to article

Authors and Affiliations

Krzysztof Rogowski
1
Ryszard Maroński
1
Janusz Piechna
1

  1. Institute of Aeronautics and Applied Mechanics, Warsaw University of Technology, Poland.

This page uses 'cookies'. Learn more