Solid and fluid mechanics case studies in advanced electronic packaging.

摘要

A set of novel approaches in solid and fluid mechanics are used to solve a subset of complex problems in the field of advanced electronic packaging. In the solid mechanics sections of this work, the classical laminate theory was used to investigate the warpage of a Printed Wiring Board (PWB) due to the application of a compression connector. Both Navier and Levy approaches were calculated and discussed as a means of solving the biharmonic equation for profiling the warpage of the PWB. A second study in solid mechanics is presented that investigates viscoelastic properties of polymers and the Time-Temperature-Superposition (TTSP) method to predict the creep behavior of the PWB due to the loading condition of the previous study. The TTSP results are compared to power law constitutive values for the prediction of creep. In the fluid mechanics sections, the creation of dielectric nanofluids is investigated for improving the thermal performance of direct immersion cooling. The thermal conductivity of the fluid is predicted by Brownian motion and is compared to measured values. A nanoscale thermal interface is also utilized to further increase thermal performance. A second fluid mechanics study investigates the use of a gamma-alumina nanoparticles mixed in water to improve the transient response of a heat pipe. A transient lumped mass model is used to solve the heat equation and produce a closed-form solution. The Rohsenow nucleate pool-boiling equation is used to predict the effectiveness of the nanofluid in enhancing the transient response of the heat pipe, and the predicted values are compared to measured data.