Seminars

PMMH’s weekly seminar is held every Friday at 11 am (map)

Contact :
Stéphane Perrard
Etienne Reyssat
Virgile Thiévenaz
responsables-seminaires (arobase) pmmh.espci.fr

PMMH
BARRE CASSAN
BAT A 1ER ETAGE CASE 18
7 QUAI SAINT BERNARD
75005 PARIS
France

Tel : (33) 1 40 79 45 22


Séminaire PMMH : Thomas Engels (LMD, ENS)

Vendredi 8 juin 2018 de 11h00 à 12h00 - Salle réunion PMMH 1

The impact of turbulence on flying insects in tethered and free flight : high-resolution numerical experiments

Flapping insects are remarkably agile fliers, adapted to a highly turbulent environment. We present a series of high resolution numerical simulations of a bumblebee interacting with fully developed turbulent inflow. We consider both tethered and free flight, the latter with all six degrees of freedom coupled to the Navier–Stokes equations. To this end we vary the characteristics of the turbulent inflow, either changing the turbulence intensity or the spectral distribution of turbulent kinetic energy. Active control is excluded in order to quantify the passive response real animals exhibit during their reaction time delay, before the wing beat can be adapted. Modifying the turbulence intensity shows no significant impact on the cycle-averaged aerodynamical forces, moments and power, compared to laminar inflow conditions. The fluctuations of aerodynamic observables, however, significantly grow with increasing turbulence intensity. Changing the integral scale of turbulent perturbations, while keeping the turbulence intensity fixed, shows that the fluctuation level of forces and moments is significantly reduced if the integral scale is smaller than the wing length. Additional simulations with laminar inflow, in which the insect's heading is not aligned with the mean flow, shed light on the role of the incident flow. This is relevant to understand the change of the insect's orientation due to turbulent perturbations. Our study shows that the scale-dependent energy distribution in the surrounding turbulent flow is a relevant factor conditioning how flying insects control their body orientation.


PDF - 906.4 kio

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Seminars  (4)

  • Séminaire PMMH - Francesca Borghi Università degli Studi di Milano
    Vendredi 20 juin de 11h00 à 12h00 - Salle réunion PMMH 1
    REPROGRAMMABLE HARDWARE FOR DATA PROCESSING AT THE EDGE : A NEW COMPUTING PARADIGM BASED ON NEUROMORPHIC SYSTEMS
    The brain's ability to perform efficient and fault-tolerant data processing is strongly related with its peculiar interconnected adaptive architecture, based on redundant neural circuits interacting at different scales. By emulating the brain's processing and learning mechanisms, computing technologies strive to (…)
  • Séminaire PMMH - Francesca Borghi Università degli Studi di Milano
    Vendredi 20 juin de 11h00 à 12h00 - Salle réunion PMMH 1
    REPROGRAMMABLE HARDWARE FOR DATA PROCESSING AT THE EDGE : A NEW COMPUTING PARADIGM BASED ON NEUROMORPHIC SYSTEMS
    The brain's ability to perform efficient and fault-tolerant data processing is strongly related with its peculiar interconnected adaptive architecture, based on redundant neural circuits interacting at different scales. By emulating the brain's processing and learning mechanisms, computing technologies strive to (…)
  • Séminaire PMMH - Salvatore Federico (University of Calgary, Canada)
    Vendredi 4 juillet de 11h00 à 12h00 - Salle réunion PMMH 1
    Continuum Mechanics of Hydrated Fibre-Reinforced Soft Tissues
    Biological tissues can be represented as bi-phasic continua, with a porous solid phase saturated by an interstitial fluid and reinforced by collagen fibers. This lecture will give an overview of the modelling techniques for fibre-reinforced porous composite materials with statistical orientation of the fibers. Both (…)
  • Séminaire PMMH - Salvatore Federico (University of Calgary, Canada)
    Vendredi 4 juillet de 11h00 à 12h00 - Salle réunion PMMH 1
    Continuum Mechanics of Hydrated Fibre-Reinforced Soft Tissues
    Biological tissues can be represented as bi-phasic continua, with a porous solid phase saturated by an interstitial fluid and reinforced by collagen fibers. This lecture will give an overview of the modelling techniques for fibre-reinforced porous composite materials with statistical orientation of the fibers. Both (…)

Information for the speakers

The audience is composed of people with rather heterogeneous backgrounds including specialists in solids, fluids, granular flows, statistical physics... so the idea is to keep your talk understandable by people not necessarily working in your field... The seminar time slot runs from 11am to noon so the best is to make the talk last around 45 minutes to leave some time for discussion.

Link to cofee seminar (internal, every Thursday)


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Practical information

Laboratoire : 01 40 79 45 22
Directeur : Ramiro GODOY DIANA
Codirecteur : Laurent DUCHEMIN
Administratrice : Frédérique AUGER (01 40 79 45 22)
Gestionnaire : Claudette BAREZ (01 40 79 58 53)
Courriel : dir (arobase) pmmh.espci.fr