Microscale Two-Step Models

Microscale thermal transport phenomenon involves complex transfer mechanism of free electrons and phonons. The molecular dynamics and processes are not significant in most of the microscopic engineering applications. However, scale effects become extremely important in system with sudden high heat flux irradiation by laser pulses and some other dimensionally space- and time-governed problems. Anisimov etal. (1974) proposed the first two-step model for microscale conduction as 

This transforms the two-step model (equations (8.74) and (8.76)) to hyperbolic in nature. 

Qiu and Tien (1992, 1993) proposed the coupling factor G for radiation deposition in 

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