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A New Eulerian Model for Turbulent Evaporating Sprays in Recirculating Flows

Wittig, S. (author), Hallmann, M. (author), Scheurlen, M. (author), Schmehl, R. (author)

A new Eulerian model for the computation of turbulent evaporating sprays in recirculating flows is derived. It comprises droplet heating and evaporation processes by solving separate transport equations for the droplet's temperature and diameter. Full coupling of the droplet and the gaseous phase is achieved by the exchange of source terms due...

conference paper 1993

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Efficient Numerical Calculation of Evaporating Sprays in Combustion Chamber Flows

Schmehl, R. (author), Klose, G. (author), Maier, G. (author), Wittig, S. (author)

Representing two different conceptual approaches, either Eulerian continuum models or Lagrangian particle models are commonly applied for the numerical description of dispersed two phase flows. Taking advantage of the positive features inherent to each model, a combination approach is presented in this study for the efficient computation of...

conference paper 1998

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CFD Analysis of Fuel Atomization, Secondary Droplet Breakup and Spray Dispersion in the Premix Duct of a LPP Combustor

Schmehl, R. (author), Maier, G. (author), Wittig, S. (author)

The two phase flow in the premix duct of a LPP combustor is computed using a Lagrangian droplet tracking method. To reproduce the characteristic spray structure of an air-assisted pressure-swirl atomizer, a sheet spray model is de-rived from measured sheet parameters and combined with an advanced concept for modeling secondary atomization...

conference paper 2000

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An extension of dynamic droplet deformation models to secondary atomization

Bartz, F.O. (author), Schmehl, R. (author), Koch, R. (author), Bauer, H.J. (author)

A detailed model for secondary atomization of liquid droplets by aerodynamic forces is presented. As an empirical extension of dynamic droplet deformation models, it accounts for temporal variations of the relative velocity between droplet and gas phase during the deformation and breakup process and describes the characteristic features of...

conference paper 2010

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Kite power technology

Schmehl, R. (author)

De wind hoog boven de grond wordt gezien als een potentieel zeer grote bron van duurzame energie. Conventionele windturbines met hun starre toren zullen nooit in staat zijn deze bron ten volle te benutten. Eén van de mogelijke oplossingen om deze wind op grote hoogte te benutten, is het gebruik van kite power systemen. De kite power...

journal article 2011

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Modeling and simulation of kite power systems

Schmehl, R. (author)

conference paper 2011

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Modeling and simulation of kite power systems

Schmehl, R. (author), Breukels, J. (author), Schwoll, J. (author), de Groot, S. (author)

conference paper 2011

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Effect of design parameters on the flight dynamics of a Kiteplane

Terink, E.J. (author), Breukels, J. (author), Schmehl, R. (author), Ockels, W.J. (author)

conference paper 2011

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Model comparison for angle droplet fragmentation under varying accelerations

Bartz, F.O. (author), Guildenbecher, D.R. (author), Schmehl, R. (author), Koch, R. (author), Bauer, H.J. (author), Sojka, P.E. (author)

Different models for single droplet fragmentation have been assessed for different initial accelerations in the bag and sheet-thinning regimes. The predictions have been compared to high-speed-video sequences where a single droplet is injected in a cross-flow of air. It is concluded that the modeling of the temporal evolution of the breakup...

conference paper 2011

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Efficiency of kite power systems in pumping operation

Fechner, U. (author), van der Vlugt, R. (author), Schmehl, R. (author), Ockels, W.J. (author)

Seminar organized by Delft University Wind energy research institute for European Academy of Wind Energy

conference paper 2011

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Die Kraft des Drachens

Schmehl, R. (author)

Der Großteil atmosphärischer Windenergie ist mit normalen Turbinen unerreichbar. Schnell fliegende Lenkdrachen könnten sie ernten.

journal article 2011

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Large-scale power generation with kites

Schmehl, R. (author)

journal article 2012

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Aerodynamic Performance Prediction of a Tetrahedral Kite

Ashari, B. (author), Schmehl, R. (author), Veldhuis, L. (author)

conference paper 2013

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Feed-Forward Control of Kite Power Systems

Fechner, U. (author), Schmehl, R. (author)

Kite power technology is a novel solution to harvest wind energy from altitudes that can not be reached by conventional wind turbines. The use of a lightweight but strong tether in place of an expensive tower provides an additional cost advantage, next to the higher capacity factor. This paper describes a method to estimate the wind velocity at...

journal article 2014

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A Tool for Aerodynamic Analysis of Flexible Kites

Franca, B. (author), Schmehl, R. (author)

conference paper 2015

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Multiple-Wake Vortex Lattice Method for Airborne Wind Energy Membrane-Wing Kites

Leuthold, R. (author), De Oliveira, G. (author), Schmehl, R. (author)

conference paper 2015

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Fluid-Structure Interaction of an Inflatable Kite Wing

Rajan, N.K. (author), Viré, A. (author), Schmehl, R. (author), Van Bussel, G.J.W. (author)

conference paper 2015

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Pumping kites wind farm

Faggiani, P. (author), Schmehl, R. (author), Van der Vlugt, R. (author)

conference paper 2015

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Preparing the Road for 24 Hours Flight Operation of a Pumping Kite Power System

Braun, L. (author), Schmehl, R. (author), Friedl, F. (author), Grete, C. (author), Peschel, J. (author), Tzavellas, A. (author)

conference paper 2015

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Multiple Wake Vortex Lattice Method for Airborne Wind Energy Membrane-Wing Kites (poster)

Leuthold, R. (author), De Oliveira Andrade, G.L. (author), Schmehl, R. (author)

conference paper 2015