TY - GEN
T1 - Thermal stress reduction and optimization for orthotropic composite boards
AU - Khalilollahi, Amir
AU - Warley, Russell L.
PY - 2005
Y1 - 2005
N2 - Composite printed electronic boards are susceptible of structural failure or irreversible damage under thermally raised stresses. A thermal/structural finite element model is integrated in this study to enable the predictions of the temperature and stress distribution of vertically clamped parallel circuit boards that include series of symmetrically mounted heated electronic modules (chips). The board is modeled as a thin plate containing four heated flush rectangular areas that represent the electronic modules. The finite element model should be to able to accept the convection heat transfer on the board surface, heat generation in the modules, and directional conduction inside the board. A detailed 3-D CFD model is incorporated to predict the conjugate heat transfer coefficients that strongly affect the temperature distribution in the board and modules. Structural analyses are performed by a FE model that uses the heat transfer coefficients mentioned above, and structural elements capable of handling orthotropic material properties. The stress fields are obtained and compared for the models possessing different fiber orientations and fiber volume fractions. Appreciable differences in stress and thermal gradient fields were observed. The values of fiber volume fraction and fiber orientation at which to conduct analyses was guided by experimental design (DOE) ideas leading to a metamodel of the stress intensity and temperature gradient in the board which was used to represent the complied results of this study.
AB - Composite printed electronic boards are susceptible of structural failure or irreversible damage under thermally raised stresses. A thermal/structural finite element model is integrated in this study to enable the predictions of the temperature and stress distribution of vertically clamped parallel circuit boards that include series of symmetrically mounted heated electronic modules (chips). The board is modeled as a thin plate containing four heated flush rectangular areas that represent the electronic modules. The finite element model should be to able to accept the convection heat transfer on the board surface, heat generation in the modules, and directional conduction inside the board. A detailed 3-D CFD model is incorporated to predict the conjugate heat transfer coefficients that strongly affect the temperature distribution in the board and modules. Structural analyses are performed by a FE model that uses the heat transfer coefficients mentioned above, and structural elements capable of handling orthotropic material properties. The stress fields are obtained and compared for the models possessing different fiber orientations and fiber volume fractions. Appreciable differences in stress and thermal gradient fields were observed. The values of fiber volume fraction and fiber orientation at which to conduct analyses was guided by experimental design (DOE) ideas leading to a metamodel of the stress intensity and temperature gradient in the board which was used to represent the complied results of this study.
UR - http://www.scopus.com/inward/record.url?scp=29644438446&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=29644438446&partnerID=8YFLogxK
U2 - 10.1115/HT2005-72570
DO - 10.1115/HT2005-72570
M3 - Conference contribution
AN - SCOPUS:29644438446
SN - 0791847314
SN - 9780791847312
T3 - Proceedings of the ASME Summer Heat Transfer Conference
SP - 267
EP - 272
BT - Proceedings of the ASME Summer Heat Transfer Conference, HT 2005
T2 - 2005 ASME Summer Heat Transfer Conference, HT 2005
Y2 - 17 July 2005 through 22 July 2005
ER -