Now showing items 41-60 of 81

    • Multifractal analysis of a wake for a single wind turbine 

      Strijhak, Sergei; Redondo Apraiz, José Manuel; Tellez Alvarez, Jackson David (2017)
      Conference report
      Open Access
      Wind energy is an important component of renewable energy sources. Studying of turbulent wakes for wind turbines and interactions with Atmospheric Boundary Layer is an urgent problem. The theory of chaos and fractal geometry ...
    • Multifractal analysis of SAR of the ocean surface, currents, eddy structure, oil slicks and diffusivity analysis 

      Redondo Apraiz, José Manuel; Grau, J.; Matulka, Anna Magdalena; Platónov, Alexéi Konstantínovich (2010)
      Conference lecture
      Restricted access - publisher's policy
    • Multifractal analysis of sar of the ocean surface, currents, eddy structure, oil slicks and diffusivity analysis 

      Redondo Apraiz, José Manuel; Grau, J.; Matulka, A.; Platónov, Alexéi Konstantínovich (SARTI (Technological Development Centre of Remote Acquisition and Data processing Systems), 2008-04-08T15:52:51Z)
      Article
      Open Access
    • Multifractal analysis of turbulent wakes for model wind turbines using large eddy simulation 

      Tellez Alvarez, Jackson David; Kryuchkova, Arina; Strijhak, Sergei; Redondo Apraiz, José Manuel (2018)
      Conference report
      Open Access
      Over the last years it has become evident that one of the greatest problems during wind turbine operations is related to intermittency between turbulent flow and the blades. An adjacent problem consists in coupling and ...
    • Multifractal observations of eddies, oil spills and natural slicks in the ocean surface 

      Platónov, Alexéi Konstantínovich; Carrillo Cortés, José Alejandro; Matulka, Anna Magdalena; Sekula, Emil; Grau Barceló, Joan; Redondo Apraiz, José Manuel; Tarquis, Ana Maria (2009-06-11)
      Article
      Restricted access - publisher's policy
      Natural and man-made distributions of tensioactive substance concentrations in the sea surface features exhibit self-similarity at all radar reflectivity levels when illuminated by SAR. This allows the investigation of the ...
    • Multiscale analysis of SAR from the earth surface 

      Redondo Apraiz, José Manuel; Tarquis, Ana Maria; Matulka, Anna Magdalena; Platónov, Alexéi Konstantínovich (Universidad Complutense de Madrid (UCM), 2010)
      Conference lecture
      Open Access
      The use of Synthetic Aperture Radar (SAR) to investigate the earth’s surface provides a wealth of useful information. Here we will discuss some recent fractal and multi-fractal techniques used to identify oil spills and ...
    • Multiscaling properties on sequences of turbulent plumes images 

      Lopez Gonzalez-Nieto, Pilar; Tarquis Alfonso, Ana Maria; Matulka, Anna Magdalena; Skadden, Benjamin; Redondo Apraiz, José Manuel (2017-12-01)
      Article
      Open Access
      A multifractal analysis on a finite-range-scale of the plume concentration images at different experimental conditions (the height of the source Ho), where the measure is the grey value of the image (from 0 to 255), was ...
    • Non-linear fractal percolation experiments in carstic and aggregation soils 

      Chierubini, Claudia; Tarquis Alfonso, Ana Maria; Redondo Apraiz, José Manuel; Pastore, Nicola (2014)
      Conference report
      Open Access
      The present study compares the performances and reliabilities of the classical Mobile – Immobile Model (MIM) and the Explicit Network Model (ENM) that takes expressly into account the network geometry for describing tracer ...
    • Numerical LES models of Richtmyer-Meshkov and Rayleigh-Taylor instabilities 

      Garzón Bedoya, Germán; Redondo Apraiz, José Manuel; Rozanov, V.B.; Gushkov, S. (Universidad Complutense de Madrid (UCM), 2010)
      Conference lecture
      Open Access
      Experimental and numerical results on the advance of a mixing or non-mixing front occurring at a density interface due to gravitational acceleration are analyzed considering the fractal and spectral structure of the front. ...
    • Ocean classification of dynamical structures detected by SAR and spectral methods 

      Redondo Apraiz, José Manuel; Martínez Benjamín, Juan José; Tellez Alvarez, Jackson David; Jorge Sánchez, Juan; Díez Rilova, Margarita; Sekula, Emil (European Space Agency (ESA), 2016)
      Conference report
      Open Access
      We discuss a taxonomy of different dynamical featuresin the ocean surface and provide some eddy and frontstatistics, as well as describing some events detected byseveral satellites and even with additional cruise observationsand ...
    • Oil spill detection and prediction in the NW Mediterranean Sea, multifractal methods for space based SAR analysis 

      Redondo Apraiz, José Manuel; Matulka, Annia; Platónov, Alexéi Konstantínovich (Atenea. Campus digital UPC, 2009)
      Conference report
      Restricted access - publisher's policy
      This paper presents a statistical analysis of the oil spill detection in European coastal waters, as well as a methodological description on how to distinguish by means of multi-fractal analysis oil spills and biological ...
    • Oil spill detection and prediction in the NW Mediterranean Sea: new multifractal methods for SAR analysis 

      Redondo Apraiz, José Manuel; Platónov, Alexéi Konstantínovich (2010)
      Conference lecture
      Restricted access - publisher's policy
      The oil pollution of Gulf of Lion in the NW Mediterranean has been studied with SAR images during the period 1999 -2005. We have analyzed these SAR images with respect to other surface features such as wind, river plumes, ...
    • On the entrainment coefficient in a forced plume: quantitative effects of source parameter 

      Matulka, Anna Magdalena; Lopez Gonzalez-Nieto, Pilar; Redondo Apraiz, José Manuel; Tarquis Alfonso, Ana Maria (University of Thechnology and Agriculture Nicholas Copernicus University, 2014-02-24)
      Article
      Open Access
      The behavior of a forced plume is mainly controlled by the source buoyancy and momentum fluxes and the efficiency of turbulent mixing between the plume and the ambient fluid (stratified or not). The interaction between the ...
    • Particle dispersion in two-dimensional turbulence: a comparison with 2-D kinematic simulation 

      Castilla López, Roberto; Redondo Apraiz, José Manuel; Gámez Montero, Pedro Javier; Babiano, Armando (University of Thechnology and Agriculture Nicholas Copernicus University, 2007-03)
      Article
      Open Access
      We study numerically the comparison between Lagrangian experiments on turbulent particle dispersion in 2-D turbulent flows performed, on the one hand, on the basis of direct numerical simulations (DNS) and, on the ...
    • Percolation experiments in complex fractal media 

      Redondo Apraiz, José Manuel; Tarquis, Ana Maria; Cherubini, Claudia; Lopez Gonzalez-Nieto, Pilar; Vila, Teresa (2013)
      Conference report
      Open Access
    • Rayleigh–Taylor mixing analysis and intermittency 

      Redondo Apraiz, José Manuel (2017)
      Conference report
      Open Access
    • Relationship between intermittency and stratification 

      Vindel, Jose M.; Yagüe, Carlos; Redondo Apraiz, José Manuel (2009-04-09)
      Article
      Restricted access - publisher's policy
      A formal analogy exists between 2D turbulence and 3D turbulence with stratification and rotation. Although the effect of the rotation, to the scale typical of the turbulence, is negligible in the atmosphere, we have found ...
    • Richmyer-Meshkov and Rayleigh-Taylor turbulent mixing fronts and instabilities 

      Redondo Apraiz, José Manuel; Garzón Bedoya, Germán; Rozanov, V.B.; Gushkov, S. (Universidad Complutense de Madrid (UCM), 2010)
      Conference lecture
      Open Access
      Plume and Jets are released in an enclosed volume of water and depending on the initial and environmental conditions, the global mixing efficiency of the overall process is measured. The behaviour of individual plumes is ...
    • Richtmyer-meshkov and rayleigh-taylor fractal mixing 

      Redondo Apraiz, José Manuel; Tellez Alvarez, Jackson David; Vila, Teresa; Lopez Gonzalez-Nieto, Pilar; Sanchez, Jesus Maria (2016)
      Conference report
      Open Access
      Turbulence affects molecular mixing in a large variety of physical processes both in the environment, in astrophysics and in industrial situations. In some events it is interesting to enhance the transport of mass, heat, ...
    • Richtmyer-meshkov and rayleigh-taylor fractal mixing 

      Redondo Apraiz, José Manuel; Vila Esteve, Maria Teresa; Tellez Alvarez, Jackson David; Lopez Gonzalez-Nieto, Pilar; Sánchez, Miguel Ángel (Institute of Thermomechanics, Academy of Sciences of the Czech Republic, 2016-02-10)
      Article
      Open Access
      Turbulence affects molecular mixing in a large variety of physical processes both in the environment, in astrophysics and in industrial situations. In some events it is interesting to enhance the transport of mass, heat, ...