@Article{CostaVlas:2013:EvInUn,
               author = "Costa, Rafael Lopes and Vlassov, Valeri",
          affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and {Instituto 
                         Nacional de Pesquisas Espaciais (INPE)}",
                title = "Evaluation of Inherent Uncertainties of the Homogeneus Effective 
                         Thermal Conductivity Approach in Modeling of Printed Circuit 
                         Boards for Space Applications",
              journal = "Journal of Electronics Cooling and Thermal Control",
                 year = "2013",
               volume = "3",
                pages = "35--41",
                month = "Mar.",
             keywords = "PCB, spacecraft thermal control, effective conductivity.",
             abstract = "Electronic components are normally assembled to printed circuit 
                         boards (PCBs). Such components generate heat in operation which 
                         must be conducted away efficiently from the small mounting areas 
                         to frames where the PCB is fixed. The temperature of the component 
                         depends on heat dissipation rate, technology and parameters of 
                         mounting, component placement and finally effective thermal 
                         conductivity (keff) of the board. The temperature of some 
                         components may reach significant magnitudes over 100?C while the 
                         PCB frame is kept at near-ambient temperature. The reliability of 
                         electronic components is directly related to operating 
                         temperature; therefore the thermal project should be able to 
                         provide a correct temperature prediction of all PCB components 
                         under the hottest operational condition. In space applications, 
                         the main way to spread and reject heat of electronic equipment is 
                         by thermal conduction once there is no air available to apply 
                         convection-based cooling techniques. The PCB keff is an important 
                         parameter for the electronics thermal analysis when the PCB is 
                         modeled as a simplified homogeneous board with a unique thermal 
                         conductivity. In this paper, an intrinsic uncertainty of such 
                         approach is firstly reveled and its magnitude is evaluated for a 
                         real space use PCB. The simulation uses SINDA/FLUINT Thermal 
                         Desktop and aims to determine the keff of the PCB by comparison 
                         between a detailed multi-layered anisotropic model and an 
                         equivalent homogeneous single-layer model. The model was validated 
                         using available data for two-layered FR4-copper PCB. Multiple 
                         simulations are performed with different dissipating component 
                         position and mounting area.",
                  doi = "10.4236/jectc.2013.31005",
                  url = "http://dx.doi.org/10.4236/jectc.2013.31005",
                 issn = "2162-6162",
             language = "en",
           targetfile = "JECTC_2013032914010711.pdf",
                  url = "http://www.scirp.org/journal/jectc/",
        urlaccessdate = "13 maio 2024"
}