Microstructured Heat Exchanger Surfaces for Low-Pressure-Loss Transfer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current heat transfer enhancement techniques for heat exchangers, such as those described in PTL 1 and PTL 2, still have room for improvement in heat transfer performance, particularly regarding the shape and size of fine structure bodies forming nanoporous layers and their impact on boundary layer thickness.
Innovation Solution
A heat exchanger with a heat transfer unit that includes a contact surface with a fin structure body having a height of 10 µm or less and a surface area 10 times or more than a smooth surface, utilizing a dendritic or needle-like structure made of the same material as the heat transfer units to enhance heat transfer performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If a nanoporous layer is formed on a heat transfer surface, then heat transfer performance is improved, but device complexity increases
Solution Approach 1:
The patent applies porous materials by forming a nanoporous layer on the heat transfer surface using copper oxide particulates (1 μm or less) and copper oxide nanoparticles (0.1 μm or less). This porous structure increases the effective heat transfer area and enhances molecular diffusion in the boundary layer, thereby improving heat transfer performance without requiring complex multi-component systems.
Solution Approach 2:
The patent uses composite materials by combining copper oxide particulates and copper oxide nanoparticles to form a hierarchical porous structure. This composite approach creates a dense lower layer with particulates and a porous upper layer with nanoparticles, optimizing both structural integrity and heat transfer enhancement while avoiding more complex material compositions.
2Productivity
If the surface area of heat transfer unit is increased by adding fin structure, then heat transfer performance is improved, but pressure loss increases
Solution Approach 1:
The patent applies dimensionality change by transitioning from a smooth two-dimensional surface to a three-dimensional fin structure with height (10 μm or less). This vertical dimension addition increases the effective heat transfer area by 10 times or more compared to a smooth surface, significantly enhancing heat transfer performance without proportionally increasing pressure loss.
3Productivity
If fin height is increased to increase surface area, then heat transfer performance is improved, but boundary layer thickness increases reducing effectiveness
Solution Approach 1:
The patent applies parameter changes by precisely controlling the fin height parameter to be 10 μm or less. This parameter optimization ensures that the fin structure remains within the boundary layer region, maximizing heat transfer effectiveness. The specific height constraint prevents the fins from extending too far into the flow, which would increase boundary layer thickness and reduce heat transfer efficiency.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This configuration improves heat transfer performance by increasing the surface area while maintaining low pressure loss, with further enhancement in turbulent gas flows, and reduces the number of heat transfer units required, leading to cost savings and miniaturization.
Implementation Method 1
a contact surface of the heat transfer unit to be in contact with the gas is provided with a fin structure body which has a height of 10 μm or less and a surface area of 10 times or more of a smooth surface
Implementation Method 2
improves heat transfer performance by increasing the surface area while maintaining low pressure loss, with further enhancement in turbulent gas flows
Data Source
Figure 1
Figure 2
Figure 3~4
AI summary
Provided is a heat exchanger having improved heat transfer performance. A heat exchanger (100) according to the present invention includes a heat transfer unit (102) configured to perform heat exchange by contact with gas (112), and a contact surface (102a) of the heat transfer unit (102) to be in contact with the gas (112) is provided with a fine structure body (102b) which has a height of 10 µm or less and a surface area of 10 times or more of a smooth surface. The gas (112) desirably has a Reynolds number of 30,000 or more, and the fine structure body (102b) is desirably formed of the same material as that of a base material forming the contact surface (102a). Moreover, the fine structure body (102b) desirably has heat conductivity equal to or larger than the base material forming the contact surface (102a).