Modeling the Dominant Flow an‎d Heat-Transfer Dynamics in Miniaturized Heat Pipes (Millimeter to Micrometer Scales)

10/19/2026 12:00:00 AM

The ever-increasing growth of electronic systems an‎d data centers has intensified the need for efficient thermal management at millimeter to micrometer scales. This research is twofold: (a) a comprehensive analysis of Flat Heat Pipes (FHP) an‎d (b) the development of a Phase-Field Lattice Boltzmann Model (PF-LBM) for Micro Heat Pipes (MHP). In the FHP section, the phase-change mechanism within the evaporator wick is first modeled for two distinct regimes: surface evaporation an‎d ‘capillary-fed boiling’. Subsequently, inspired by the flow in channels with porous walls (i.e., normal suction/injection), the vapor core pressure dro‎p is asymptotically derived for one-sided an‎d two-sided scenarios. The results indicate that in slender FHPs, the vapor core pressure dro‎p becomes the dominant factor. For Ultra-Thin Heat Pipes (UTFHPs), the introduction of tuning coefficients, β (for the adiabatic section) an‎d α (for the condenser), reduced the pressure dro‎p estimation error, achieving excellent agreement with reference data. In the MHP section, a 2D GPU-accelerated (PyTorch) PF-LBM was implemented, wherein phase change is imposed through a source term in the Allen-Cahn equation, driven by the ‘sensible heat’ of the superheated/subcooled phase. Validation against the classical Stefan problem demonstrated the model’s accuracy at large density an‎d thermal conductivity ratios. This framework presents a ‘roadmap’ for selec‎ting the appropriate asymptotic scenario an‎d estimating the pressure an‎d temperature dro‎ps for FHP/UTFHP design. Furthermore, it provides an accurate numerical platform for the study of MHPs, with a particular focus on thin-film phase change phenomena.

لوله حرارتي تخت , روش بولتزمن شبكه‌اي , جوشش , تغيير فاز , جريان درون كانال

Flat Heat Pipes , Lattice Boltzmann Method , Boiling , Phase Change , Flow Within a Channel

Ali Bagheri Barmas

Dr. Hosseinalipour