@TechReport{AssisFach:2014:DyFlNa,
               author = "Assis, Giovanna Querido Marcondes de and Fachini Filho, Fernando",
                title = "Dynamics of flame in narrow channel",
          institution = "Instituto Nacional de Pesquisas Espaciais",
                 year = "2014",
                 type = "RDP",
              address = "S{\~a}o Jos{\'e} dos Campos",
                 note = "{Bolsa PIBIC/INPE/CNPq}",
             keywords = "flames, narrow channel.",
             abstract = "We analyse premixed ames inside a narrow channel.This topic 
                         matters the most when it comes to security and propulsion. It's 
                         study started in order to analyze ames propagating in coal mines, 
                         contributing later on to chemical industries. Intrinsically, the 
                         problem is two-dimensional, but applying weight mean procedure, it 
                         is possible to describe the problem with 1D conservation equations 
                         making usage of convective heat transfer model. Considering the 
                         gas and solid phase conjugated problem, the system is adiabatic, 
                         then all heat transferred from the ame to the tube walls returns 
                         to the fuel mixture. As in most cases the heat conductivity in the 
                         solid phase is much faster than that in the gas phase, problem's 
                         description requires two main thermal zones with very dierent 
                         length scales. The largest scaled one is associated to solid phase 
                         conduction, while the smallest reefers to the gas phase. The 
                         analysis focused in showing the in uence of these two thermal 
                         zones, once their dierences contribute to the understanding of the 
                         propagation of heat on the channel wall and on the ame. Similar 
                         studies on this, however treated in porous media, show that the 
                         ame temperature will probably rise above the adiabatic values. 
                         Solving the particular equations of mass, energy and species 
                         conservation, it is used the method of singular perturbations 
                         (asymptotic expansion), mating outcomes for dierent regions. The 
                         perturbation theory provides solutions as series expansions having 
                         as parameter the ratio between the thermal conductivities of the 
                         solid and gas phases. Other parameters in the mathematical 
                         formulation are oxygen and fuel's Lewis numbers and also the 
                         convective heat transfer parameter. For conditions in which the 
                         convective heat transfer parameter is close to unit, the two 
                         phases are not in thermal equilibrium, so the heat circulation 
                         between phases happens largely and the ame temperature can reach 
                         up to twice the adiabatic temperature (theoretically estimated 
                         value). Further, a third region is analyzed along this work. It 
                         has a heat-reactive character and its length scale is appropriate 
                         to describe the ame inner structure. The inner region study 
                         coupled with the outer region one solves the problem.",
          affiliation = "{Universidade Federal de Itajub{\'a} (UNIFEI)} and {Instituto 
                         Nacional de Pesquisas Espaciais (INPE)}",
                pages = "18",
                  ibi = "8JMKD3MGP3W34R/42R323B",
                  url = "http://urlib.net/ibi/8JMKD3MGP3W34R/42R323B",
           targetfile = "Giovanna Querido Marcondes de Assis.pdf",
        urlaccessdate = "10 maio 2024"
}