Ultrafast laser heating of metals from a microscopic point of view according to Qui et al. Int. J. Heat Mass Transfer, 37, 1994, is composed of three processes: deposition of radiation energy on electrons, the transport of energy by electrons, and heating of the material lattice through electron-lattice interactions. Fourier’s model violates the causality principle because it assumes that heat flow starts (vanishes) instantaneously with the appearance (disappearance) of a temperature gradient. During a relatively slow heating process, the deposition of radiation energy can be assumed to be instantaneous and can be modeled by Fourier conduction, but its applicability to very short laser pulse duration becomes questionable: we must look for non-Fourier models. The hyperbolic heat conduction model has been investigated for more than 50 years, but it suffers from violation of the second law of thermodynamics; physically unrealistic solutions are therefore unavoidable. Successful attempts to model microscale heat transfer have been made by Qui et al., but when investigating macroscopic effects a different model is required. A universal model called the dual phase lag equation (DPL model) has been proposed recently by D.Y. Tzou, J. Heat Transfer, 117, 1995, to cover a wide range of physical responses from the microscopic to macroscopic scales in both space and time under special values of relaxation times corresponding to the temperature gradient and heat flux, respectively. In the present work we investigate femtosecond laser heating of nano-films in three dimensions using the DPL model. A numerical solution based on finite-difference method has been employed to solve the DPL heat conduction equation. A new source term has been developed to account for three-dimensional laser heating and we also investigate the temperature dependence of phase lags and thermal properties in order to accurately describe the femtosecond laser heating.

If you reference this work in a publication, please cite as follows:

Illayathambi Kunadian, J. M. McDonough, K. A. Tagavi, Numerical simulation of Heat transfer mechanisms during Femtosecond laser heating of nano-films using 3-D dual phase lag model, 2004 ASME Heat Transfer/Fluids Engineering Summer Conference, Charlotte, North Carolina, July 11-15, 2004. Illayathambi Kunadian, J. M. McDonough, An efficient numerical procedure for solving a microscale heat transport equation during femtosecond laser heating of Nanoscale metal films, Heat Transfer Conference and InterPACK, San Francisco. July 17-22, 2005. Illayathambi Kunadian, Numerical analysis of thermal transport phenomena in nano-films using 3-D dual phase lag (DPL) heat conduction model, Masters Thesis, University of Kentucky, August 2004. Ravi Ranjan Kumar, Illayathambi Kunadian, book Chapter on parallelization, “Thermal Transport for Applications to Nanomachining,\" by Basil Wong and M. Pinar Mengüç, Microtechnology and MEMS Series, Springer-Verlag, Heidelberg, Germany, 2007. McDonough J. M., Illayathambi Kunadian, Yang T. L., An alternative discretization and solution procedure for the dual phase-lag equation, Journal of Computational Physics, Volume 219, Issue 1, 20 November 2006, Page 163-171. Ravi Ranjan Kumar, Illayathambi Kunadian, McDonough J. M., Mengüç M. P., Performance comparison of numerical procedures for efficiently solving a microscale heat transport equation during femtosecond laser heating of nanoscale metal films, 2005 Mechanical engineering congress and exposition, November 5-11, 2005, Orlando, Florida, USA.

• Kunadian, Illayathambi (2008), "Thermal transport in thin metal films irradiated by femtosecond laser pulses", http://thermalhub.org/resources/49, accessed on 2008-08-20 10:38:32.

  BibTex | EndNote

1. femtosecond laser
2. heat conduction
3. heat transfer
4. microscale heat conduction
5. thermal transport
6. thin films