Performance Improvement of Glass Microfiber Based Thermal Transpiration Pump Using TPMS

Area of Science:

• Materials Science
• Fluid Dynamics
• Thermal Engineering

Background:

• The Knudsen pump, a thermal transpiration membrane, induces airflow using temperature gradients without moving parts.
• Its performance is potentially improvable by reducing the colder side temperature using a thermal guard.

Purpose of the Study:

• To investigate the integration of Triply Periodic Minimal Surface (TPMS) structures as thermal guards for Knudsen pumps.
• To experimentally and computationally evaluate the impact of TPMS structures on pumping performance and temperature distribution.

Main Methods:

• Experimental and simulation-based comparison of Knudsen membranes with integrated TPMS structures.
• Analysis of flow rate and temperature distribution on the membrane surface.
• Characterization of membrane parameters: area factor, pore radius, and permeability.

Main Results:

• TPMS structures as thermal guards improved the pumping performance of Knudsen membranes.
• Diamond TPMS structures yielded the highest flow improvement, while Primitive TPMS structures showed the lowest.
• Simulation results indicated that the Diamond TPMS structure's larger contact area enhanced heat conduction away from the membrane.

Conclusions:

• Integrating TPMS structures, particularly Diamond, can significantly enhance Knudsen pump performance.
• The study identified key membrane parameters for estimating airflow and highlighted the importance of thermal management via TPMS design.