Heat exchanger
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Heat exchangers with multi-hole flat tubes experience diminished performance due to liquid refrigerant pooling in headers, leading to uneven refrigerant flow and increased pressure loss when headers are arranged vertically, causing some tubes to be submerged in liquid refrigerant during condensation.
Innovation Solution
Arranging headers horizontally in heat exchangers to reduce the risk of refrigerant flow channels being immersed in liquid refrigerant, eliminating the need to lift condensed liquid against gravity, and incorporating a gap between the header and tube bottoms to facilitate smooth liquid flow, along with varying flow channel cross-sections and heat transfer groove configurations to enhance flow resistance and heat exchange efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If the header is arranged to extend along the vertical direction, then the structure is compact, but liquid refrigerant pools in the header interior and submerges the refrigerant flow channels of bottom-positioned multi-hole flat tubes, causing diminished heat exchange performance
Solution Approach 1:
The patent inverts the conventional vertical arrangement of the header to a horizontal arrangement. This inversion prevents liquid refrigerant from submerging the refrigerant flow channels of bottom-positioned multi-hole flat tubes, thereby maintaining heat exchange performance while avoiding the pooling issue inherent in vertical configurations.
2Productivity
If the header is arranged horizontally, then liquid refrigerant pooling is reduced and heat exchange performance is maintained, but the header occupies more horizontal space
Solution Approach 1:
The patent changes the spatial orientation parameter of the header from vertical to horizontal. This parameter change fundamentally alters the behavior of liquid refrigerant within the header, preventing pooling and maintaining heat exchange efficiency, while accepting the trade-off of increased horizontal footprint.
3Volume of moving object
If multi-hole flat tubes are arranged vertically, then the structure is compact vertically, but condensed liquid refrigerant must be lifted against gravity, increasing pressure loss
Solution Approach 1:
The patent inverts the vertical arrangement of multi-hole flat tubes to a horizontal arrangement. This inversion eliminates the need to lift condensed liquid refrigerant against gravity, thereby reducing pressure loss and energy consumption while maintaining structural compactness in the vertical dimension.
4Productivity
If a gap is provided between the header and tube bottoms, then liquid refrigerant flow is facilitated and pooling is reduced, but manufacturing precision requirements increase
Solution Approach 1:
The patent applies local quality by providing a gap specifically at the bottom portion between the header and tube bottoms, while maintaining tight connections elsewhere. This localized gap facilitates liquid refrigerant flow and prevents pooling without requiring high manufacturing precision across the entire assembly, as the gap is only needed in specific locations.
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 reduces performance degradation, minimizes refrigerant retention, lowers pressure loss, and ensures smooth liquid flow, thereby maintaining efficient heat exchange and reducing the risk of refrigerant collection within the heat exchanger.
Implementation Method 1
a refrigerant that undergoes a phase change during heat exchange
Implementation Method 2
when the refrigerant changes from a gas to a liquid during condensation
Implementation Method 3
when the header is arranged so as to extend along a vertical direction, the refrigerant flow channels formed in the multi-hole flat tubes which, of the plurality of multi-hole flat tubes connected to the header, are those positioned at the bottom, will be submerged in the liquid refrigerant
Data Source
AI summary
A heat exchanger carries out heat exchange between a refrigerant that undergoes a phase change during heat exchange and another heating medium. The heat exchanger includes headers having the refrigerant flowing through interiors, a plurality of multi-hole first flat tubes, and a plurality of second flat tubes. The first flat tubes extend in a direction intersecting a lengthwise direction of the headers. The first flat tubes have a plurality of refrigerant flow channels with the refrigerant flowing through the refrigerant flow channels. The second flat tubes are stacked alternately with respect to the first flat tubes, with the other heating medium flowing through the second flat tubes. The headers are arranged to extend along a horizontal direction.