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Updated: Oct 10, 2025
08:25
Measurements of Local Instantaneous Convective Heat Transfer in a Pipe - Single and Two-phase Flow
Published on: April 30, 2018
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Heat Transport Capability and Fluid Flow Neutron Radiography of Three-Dimensional Oscillating Heat Pipes.
B Borgmeyer1, C Wilson1, R A Winholtz1
1Department of Mechanical and Aerospace Engineering, University of Missouri-Columbia, Columbia, MO 65201.
Journal of Heat Transfer
|December 8, 2021
Summary
This study explores heat transport in 3D oscillating heat pipes (OHPs). Higher heat input and operating temperatures improve OHP performance, while lower filling ratios reduce heat transfer efficiency.
Area of Science:
- Thermal Engineering
- Fluid Dynamics
- Materials Science
Background:
- Oscillating heat pipes (OHPs) are passive two-phase heat transfer devices.
- Three-dimensional (3D) OHPs offer enhanced compactness and turn density compared to planar designs.
- Understanding parameter effects is crucial for optimizing OHP performance.
Purpose of the Study:
- To experimentally investigate heat transport in 3D OHPs.
- To analyze the impact of heat input, operating temperature, and filling ratio on OHP performance.
- To visualize internal fluid dynamics using neutron radiography.
Main Methods:
- Fabrication and testing of two copper 3D OHPs with 10 and 20 turns.
- Varying heat input, operating temperature, and filling ratio (50% water).
- Recording transient and steady-state temperature data and performing neutron radiography at 30 fps.
Main Results:
- Decreased evaporator-to-condenser temperature drop at higher heat inputs due to increased condenser temperature and oscillations.
- Reduced thermal resistance with increased operating temperature.
- Neutron radiography confirmed enhanced fluid oscillations at higher heat inputs.
Conclusions:
- Higher heat input and operating temperatures enhance heat transport in 3D OHPs.
- Reduced filling ratios lead to steadier flow but diminished heat transfer performance.
- 3D OHP design shows promise for compact thermal management solutions.
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