?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adc&rft.title=Nonlinear+dynamics+of+gas-liquid+separation+in+a+capillary+microseparator&rft.creator=Radhakrishnan%2C+ANP&rft.creator=Kalliadasis%2C+S&rft.creator=Pradas%2C+M&rft.creator=Gavriilidis%2C+A&rft.description=Micro-engineered+devices+(MED)+are+seeing+a+significant+growth+in+performing+separation+processes1.+Such+devices+have+been+implemented+in+a+range+of+applications+from+chemical+catalytic+reactors+to+product+purification+systems+like+microdistillation.+One+of+the+biggest+advantages+of+these+devices+is+the+dominance+of+capillarity+and+interfacial+tension+forces.+A+field+where+MEDs+have+been+used+is+in+gas-liquid+separations.+These+are+encountered%2C+for+example%2C+after+a+chemical+reactor%2C+where+a+gaseous+component+being+produced+needs+immediate+removal+from+the+reactor%2C+because+it+can+affect+subsequent+reactions.+The+gaseous+phase+can+be+effectively+removed+using+an+MED+with+an+array+of+microcapillaries.+Phase-separation+can+then+be+brought+about+in+a+controlled+manner+along+these+capillary+structures.+For+a+device+made+from+a+hydrophilic+material+(e.g.+Si+or+glass)%2C+the+wetted+phase+(e.g.+water)+flows+through+the+capillaries%2C+while+the+non-wetted+dispersed+phase+(e.g.+gas)+is+prevented+from+entering+the+capillaries%2C+due+to+capillary+pressure.+Separation+of+liquid-liquid+flows+can+also+be+achieved+via+this+approach.+However%2C+the+underlying+mechanism+of+phase+separation+is+far+from+being+fully+understood.+The+pressure+at+which+the+gas+phase+enters+the+capillaries+(gas-to-liquid+breakthrough)+can+be+estimated+from+the+Young-Laplace+equation%2C+governed+by+the+surface+tension+(%CE%B3)+of+the+wetted+phase%2C+capillary+width+(d)+and+height+(h)%2C+and+the+interface+equilibrium+contact+angle+(%CE%B8eq).+Similarly%2C+the+liquid-to-gas+breakthrough+pressure+(i.e.+the+point+at+which+complete+liquid+separation+ceases+and+liquid+exits+through+the+gas+outlet)+can+be+estimated+from+the+pressure+drop+across+the+capillaries+via+the+Hagen-Poiseuille+(HP)+equation.+Several+groups+reported+deviations+from+these+estimates+and+therefore%2C+included+various+parameters+to+account+for+the+deviations.+These+parameters+usually+account+for+(i)+flow+of+wetted+phase+through+'n'+capillaries+in+parallel%2C+(ii)+modification+of+geometric+correction+factor+of+Mortensen+et+al.%2C+20052and+(iii)+liquid+slug+length+(LS)+and+number+of+capillaries+(n)+during+separation.+LShas+either+been+measured+upstream+of+the+capillary+zone+or+estimated+from+a+scaling+law+proposed+by+Garstecki+et+al.%2C+20063.+However%2C+this+approach+does+not+address+the+balance+between+the+superficial+inlet+velocity+and+net+outflow+of+liquid+through+each+capillary+(qc).+Another+shortcoming+of+these+models+has+been+the+estimation+of+the+apparent+contact+angle+(%CE%B8app)%2C+which+plays+a+critical+role+in+predicting+liquid-to-gas+breakthrough.+%CE%B8appis+either+assumed+to+be+equal+to+%CE%B8eqor+measured+with+various+techniques%2C+e.g.+through+capillary+rise+or+a+static+droplet+on+a+flat+substrate%2C+which+is+significantly+different+from+actual+dynamic+contact+angles+during+separation.+In+other+cases%2C+the+Cox-Voinov+model+has+been+used+to+calculate+%CE%B8appfrom+%CE%B8eqand+capillary+number.+Hence%2C+the+empirical+models+available+in+the+literature+do+not+predict+realistic+breakthrough+pressures+with+sufficient+accuracy.+Therefore%2C+a+more+detailed+in+situ+investigation+of+the+critical+liquid+slug+properties+during+separation+is+necessary.+Here+we+report+advancements+in+the+fundamental+understanding+of+two-phase+separation+in+a+gas-liquid+separation+(GLS)+device+through+a+theoretical+model+developed+based+on+critical+events+occurring+at+the+gas-liquid+interfaces+during+separation.&rft.publisher=American+Society+of+Mechanical+Engineers+(ASME)&rft.date=2018&rft.type=Proceedings+paper&rft.language=eng&rft.source=+++++In%3A++Proceedings+of+the+16th+International+Conference+on+Nanochannels%2C+Microchannels%2C+and+Minichannels+(ICNMM2018).++(pp.+ICNMM2018-7613).++American+Society+of+Mechanical+Engineers+(ASME)+(2018)+++++&rft.identifier=https%3A%2F%2Fdiscovery.ucl.ac.uk%2Fid%2Feprint%2F10059034%2F&rft.rights=open