Internal Degas Flow Path for Plate-Fin Heat Exchangers
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In plate-fin heat exchangers with multiple pass configurations, trapped air in the passages reduces efficiency and performance, as existing bleed screws or valves are ineffective in purging air from all passages.
Innovation Solution
A degas flow path is created by forming recesses and degas apertures on the heat exchanger plates, which collect and convey air through continuous channels and manifolds to an external environment, ensuring effective air purging from all passages.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a bleed screw or bleed valve is disposed at the coolant outlet spout to purge air from passages, then air removal capability is improved, but in heat exchangers with multiple parallel pass configurations, the bleed screw or valve is ineffective in purging air from all passages
Solution Approach 1:
The invention divides the air purging function into multiple segments by providing a separate air purging passage for each flow passage group. Each air purging passage is selectively communicatively coupled to its corresponding flow passage group, enabling independent and effective air removal from each segment of the heat exchanger, thereby resolving the ineffectiveness of a single bleed valve in multi-pass configurations.
Solution Approach 2:
The invention introduces air purging passages as intermediary channels that connect the flow passage groups to the exterior environment. These intermediary passages serve as dedicated conduits for air removal, bypassing the limitation of direct connection through a single bleed valve and enabling effective air purging from all passages including U-bends and remote areas.
2Productivity
If coolant is introduced to the heat exchanger during servicing or maintenance, then the heat exchanger becomes operational, but undesired air accumulates and becomes trapped in the passages formed by the plates
Solution Approach 1:
The invention implements air purging passages that are pre-configured and always available to remove air during the coolant filling process. The air purging passages are designed to be selectively opened or activated during servicing, allowing air to be removed in advance before it can accumulate and trap in the passages, thereby preventing operational issues while maintaining productivity.
Solution Approach 2:
The invention converts the harmful effect of air accumulation during coolant introduction into a beneficial process by providing dedicated air purging passages. These passages allow the air introduced during servicing to be systematically collected and removed through strategically positioned outlets, transforming the potential harm of air trapping into a controlled and efficient air removal process that actually benefits the operational readiness of the heat exchanger.
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
The continuous degas flow path effectively removes undesired air, maximizing the performance and efficiency of the heat exchanger, especially in configurations with multiple parallel passes.
Implementation Method 1
A recess (46) is formed in each of the plates (30a, 30b) and intersects with a portion (34a) of the flow passage (34). The recess (46) is configured to collect and receive air from the portion (34a) of the flow passage (34).
Implementation Method 2
A degas aperture (42) is formed on each of the plates (30a, 30b) and configured to convey the collected air from a flow path of the heat exchanger.
Data Source
AI summary
A heat exchange assembly includes an upper cover panel, a lower cover panel, a plurality of stacked plate assemblies, and a plurality of fins interposed between the plurality of plate assemblies. Each of the plurality of plate assemblies forms a flow passage for receiving a coolant. A continuous flow path extends through the heat exchange assembly. The flow path is in fluid communication with the flow passage of each of the plates and configured to convey air from each of the flow passages to an environment separate from the heat exchanger.