About
19
Publications
4,947
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
91
Citations
Citations since 2017
Introduction
Emmanuel Ruffio works at the Institut I2M-TREFLE of Bordeaux. Emmanuel does research in Heat transfer, Inverse problem, Thermodynamics.
I'm currently working on 2 subjects:
- SiGe Transistor from the heat transfer point of view
- Development of an instrumentation system for beehives
Publications
Publications (19)
This presentation gives some insights and some computations about beehive insulation. This lecture was given for the beglium association "le CARI" (https://www.cari.be/accueil/):
1) The first part is an overview of 200 papers about the use of temperature measurement in beehive.
2) The second part deals with the material of beehive walls. Wood and p...
Four empty Dadant beehives are instrumented with 5 temperature sensors to record the temperature of (1) the steal cover, (2) the overframe area, (3) the top of the hive body, (4) the bottom of the hive body, (5) the “air” temperature between the hive and the ground.
Beehives are oriented in various directions to analyze the effect of sun position....
In this paper, we propose a theoretical investigation of several configurations based on the infrared photothermal radiometry in order to estimate the thermal diffusivity of isotropic and orthotropic membranes. The front-face and rear-face experimental configurations are considered and show complementary results. Analytical approximations based on...
The front face photothermal radiometry technique has been improved in order to estimate the thermal conductivity of thin films with better accuracy compared to existing techniques. The experimental procedure is based on the front face response to a nanoseconds laser pulse repeated periodically at high frequency, i. e., a Dirac comb waveform. Averag...
1) Mesure des températures dans une ruche vide avec une résistance chauffante (0-40W) simulant la présence d'une colonie. 2) Mesure des températures dans une ruche habitée Par rapport à une ruche vide, la température dans une ruche habitée est perturbée par la présence des abeilles. La simulation numérique s'appuie sur ces perturbations pour en déd...
This work was presented during the Apimondia 2019 congress in Montreal. It shows our first results concerning the estimation of the time-varying heat power producted by a bee colony.
More details on:
http://www.lmgc.univ-montp2.fr/perso/anna-dupleix/mecanique-du-bois-wood-mechanics/
Le bois de construction des ruches est un sujet peu abordé dans le monde apicole en général. Ce projet a pour but d’étudier dans quelles mesures le matériau bois constitue potentiellement une source importante d’amélioration de l’état sanitaire et donc de la survie des colonies aujourd’hui en déclin. Ce projet interdisciplinaire adopte les outils d...
L’objet de ce travail de recherche est le bois des ruches pour les colonies d’abeilles domestiques. Il s’agit ici de questionner, au-delà de son rôle structurel fondamental, l’usage du bois dans l’habitat des abeilles : dans quelles mesures le bois promeut les conditions d’un confort, entendu comme l’ensemble des qualités sanitaires d’un environnem...
A new focus is given regarding the use of the quadrupole technique to solve heat diffusion problems with heat source in layered structures. The thermal impedances formalism is used that allows representing the heat transfer in such systems as impedances network. This approach offers a fast and accurate mean to calculate the average temperature of t...
A thermodynamic analysis of the refueling of a gaseous fuel tank and a thermal analysis of heat losses through tank walls is presented. The objective of the thermodynamic analysis is to compare the temperature and pressure evolutions coming from different equations of state and from thermodynamic tables. This comparison is performed with nitrogen a...
This theoretical and numerical study deals with the estimation of thermal diffusivities of orthotropic materials with the 3D-laser-flash method. This method consists in applying a short non-uniform heat flux to a sample in order to generate three-dimensional heat transfer. An infrared camera is used to measure the evolution of the temperature field...
This numerical study deals with the design of experiments. It aims at optimizing thermocouple positions in order to reduce uncertainties in the estimation of thermophysical properties when an inverse method is applied. The 2D system under investigation is a squared sample of orthotropic material submitted to a constant heat flux on left and bottom...
L’objet de cette étude est d’identifier une condition limite thermique de flux imposé à la surface d’un échantillon soumis à une flamme oxygène-acétylène. Cette étude s’inscrit dans le cadre de la caractérisation d’un matériau composite soumis à des conditions extrêmes. L’estimation de cette condition limite est réalisée grâce à des mesures de temp...
This study deals with the resolution of two types of inverse heat transfer problem : estimation of thermophysical parameters and estimation of thermal boundary conditions. A first part is devoted to the 3D-flash method which is used to estimate the three thermal diffusivities corresponding to the three principal directions of an anisotropic materia...
Projects
Projects (2)
1) Perform thermal analysis of different type of beehive to compare them and to identify possible improvements. We are currently working on Dadant and Log hives (Lozere, France).
2) Estimate the heat power produced by a bee colony by using temperature measurements to assess its health status. We are concerned in designing a low cost system with minimum sensors.
That is:
We want to perform thermal analysis of Dadant-type and Log-type beehives in order to design thermal models that are able to predict temperature and humidity inside an empty hive, based on external conditions. We focus on unsteady thermal analysis. The thermal modeling must succeed in describing time-varying heat transfer. Thermal parameters that appear in the model are adjusted using measurements in empty hives and inverse methods. Once adjusted, it becomes possible to do sensitivity analysis or parametric study to identify the key factors that influence temperature and humidity inside the hive.
The model may suggest some improvements of beehives (like hive orientation, wall thickness, materials...) once an objective is defined, for exemple: (1) reduce heat losses during winter, (2) reduce the sensitivity to variations of external conditions, (3) reduce solar irradiance effect on temperature during the day, etc....
External conditions are either measured: air temperature, air humidity, ground temperature, (local) luminosity, wind speed, wind direction
or estimated: solar irradiance (including shadow effect of clouds, trees, moutains...)
or computed: sun position, radiation shape factor...
Temperature sensors are cheap and widely used. They are more and more introduced in beehives but it is not clear today how we can do these temperature measurement speaks. We believe the time-varying heat power could give interesting information of the health status of a bee colony. That's why our final goal is to design a method based on thermal modeling to estimate the heat power generated by a bee colony with respect to time. Since a colony needs to maintain a specific level of temperature by generating heat, it is expected/assumed that a declining colony would lead to a decrease of the heat power produced. If we are able to estimate the heat power in real-time, at least on large timescale (severals days), we may be able to detect colonies that need cares.
Other information can be found on:
http://www.lmgc.univ-montp2.fr/perso/anna-dupleix/mecanique-du-bois-wood-mechanics/
