Del­phine Brancherie is a lec­tur­er-research sci­en­tist in the Mechan­i­cal Engi­neer­ing Depart­ment at UTC’s Rober­val Lab­o­ra­to­ry and is also in charge of the dig­i­tal mechan­ics team, one of the laboratory’s five teams with eleven lec­tur­er-research scientists.

Among the team’s research pri­or­i­ties? If we com­bine the skills of all the team’s research sci­en­tists, our activ­i­ties cov­er all ele­ments of the dig­i­tal sim­u­la­tion chain. For exam­ple, we are work­ing on test-cal­cu­la­tion dia­logue, i.e., how to make the best use of infor­ma­tion from mechan­i­cal or phys­i­cal char­ac­ter­i­za­tion upstream of sim­u­la­tion, in order to deter­mine the best mod­els and asso­ci­at­ed para­me­ters to use in sim­u­la­tions. An impor­tant part of the team’s research activ­i­ties con­sists in devel­op­ing mod­els and numer­i­cal res­o­lu­tion strate­gies ded­i­cat­ed to the study of the behav­iour of struc­tures, mate­ri­als and flu­ids. We also work on opti­miza­tion-relat­ed top­ics. Opti­miza­tion of sim­u­la­tion as such, by mak­ing it more fru­gal by reduc­ing cal­cu­la­tion times, for exam­ple, but also opti­miza­tion of the mechan­i­cal per­for­mance of a giv­en mate­r­i­al or struc­ture, pos­si­bly tak­ing into account sources of uncer­tain­ty in order to quan­ti­fy robust­ness. Research that leads to the devel­op­ment of inno­v­a­tive numer­i­cal meth­ods and per­pet­u­ates the his­tor­i­cal her­itage of the numer­i­cal mechan­ics team, among the first to deploy the finite ele­ment method in France», she adds.

Research at the cross­roads of applied math­e­mat­ics and mechan­ics has led Del­phine Brancherie to take a par­tic­u­lar inter­est in cohe­sive inter­faces as a means of pre­dict­ing frac­ture phe­nom­e­na in mate­ri­als and struc­tures. «The aim is to devel­op numer­i­cal tools that can describe the behav­iour of mate­ri­als and struc­tures from their healthy state right through to fail­ure. In oth­er words, to devel­op numer­i­cal meth­ods that can repro­duce the mechan­i­cal dam­age process­es that lead to the fail­ure of part struc­tures, tak­ing into account their archi­tec­ture or microstruc­ture», she explains.

But since then, Del­phine Brancherie has extend­ed her research to so-called coher­ent inter­faces. In con­crete terms? «These coher­ent inter­faces are the result of mod­el­ling the local phe­nom­e­na that take place on small scales when study­ing the behav­iour of nano-rein­forced mate­ri­als. Recent­ly, we have also become inter­est­ed in issues involv­ing mul­ti­phys­i­cal para­me­ters. For exam­ple, we have been work­ing with Anne-Vir­ginie Sal­sac from UTC’s BMBI (Bio-Mechan­ics & Bio-Engi­neer­ing) Lab­o­ra­to­ry on the con­di­tions for micro­cap­sule rup­ture in flu­id flow sit­u­a­tions. We have also recent­ly been work­ing with Ludovic Cau­vin on mod­el­ling ther­mo­me­chan­i­cal cou­plings in nanor­e­in­forced mate­ri­als», she points out.

Con­crete projects in progress? «I’m cur­rent­ly work­ing on an ANR project enti­tled «Influe», involv­ing Cere­ma in Com­piègne, the Pprime Insti­tute in Poitiers and the Étab­lisse­ment Pub­lic Ter­ri­to­r­i­al du Bassin Saône et Doubs (EPTB), which is respon­si­ble for water man­age­ment in the Saône water­shed. The aim of this project is to devel­op exper­i­men­tal and dig­i­tal tools to under­stand the impact of increased riv­er traf­fic on nav­i­ga­ble infra­struc­tures as such. Pprime is main­ly in charge of the exper­i­men­tal part, while UTC and Cere­ma are con­cen­trat­ing on the dig­i­tal part. We’re work­ing on this project with a col­league from Cere­ma, who is a flu­ids mechan­ics “com­pu­ta­tion­al­ist” and has a very good com­mand of the tools need­ed to pre­dict the hydro­dy­nam­ics asso­ci­at­ed with the pas­sage of barges, while I’m con­tribut­ing my skills in sol­id mechan­ics to under­stand and there­fore antic­i­pate the impact of these pas­sages on the porous mate­r­i­al of the canal/river banks. What we’re par­tic­u­lar­ly inter­est­ed in is the effect of increased riv­er freight traf­fic on bank sta­bil­i­ty, with the aim of mak­ing bank pro­tec­tion as nat­ur­al as pos­si­ble. The aim is to pro­vide answers to ques­tions such as: are river­banks and infra­struc­tures threat­ened in their cur­rent state? What pre­ven­tive mea­sures can be imple­ment­ed to avoid exces­sive dam­age? And final­ly, what type of nat­ura­bank pro­tec­tion should be put in place, and how should these pro­tec­tions be qual­i­fied,» con­cludes Del­phine Brancherie.

This project has just com­menced and should cul­mi­nate in the launch of a PhD the­sis in the com­ing months.

MSD