Parallel-Serial OGV Heat Exchanger Network for Oil Cooling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing gas turbine engine oil cooling systems face challenges in efficiently cooling engine oil and electric generator oil due to the high pressure drop requirements across multiple fan outlet guide vanes (OGVs) used as heat exchangers, which can exceed the available oil pressure budget, and result in fan air drag penalties.
Innovation Solution
A hybrid outer guide vane heat exchanger apparatus is implemented, featuring a circular row of fan outlet guide vanes with networked guide vane heat exchangers connected both in series and parallel, reducing pressure drop and eliminating the need for additional cooling elements like brick or surface coolers, thereby optimizing oil cooling and reducing fan air losses.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If multiple OGVs are used as heat exchangers to cool engine oil, then cooling effectiveness is improved, but oil pressure drop increases beyond available budget
Solution Approach 1:
The oil cooling system is segmented into multiple parallel flow paths through the OGV heat exchangers. Instead of forcing all oil through a single high-pressure-drop path, the system divides the oil flow into several parallel channels, reducing the pressure drop across each individual OGV while maintaining overall cooling effectiveness through the combined heat exchange area of multiple vanes.
Solution Approach 2:
The system uses more OGVs than the minimum single-unit requirement, distributing the heat exchange function across multiple vanes. This partial distribution of the cooling function across parallel paths reduces the pressure burden on each individual vane while collectively achieving the required cooling performance.
2Temperature
If traditional brick coolers or surface coolers are used for oil cooling, then cooling function is provided, but fan air drag penalty increases
Solution Approach 1:
The cooling function is merged with the existing OGV structure that is already part of the fan assembly. By integrating heat exchangers into the OGVs, the system combines the flow guidance function of the vanes with the heat exchange function, eliminating the need for separate brick coolers or surface coolers that would add additional air drag penalties to the fan system.
Solution Approach 2:
The OGVs serve multiple functions: they guide the fan airflow (original function) and simultaneously act as heat exchangers for oil cooling (added function). This multi-functionality eliminates the need for dedicated cooling components that would separately impede fan airflow, thereby reducing overall energy loss.
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 hybrid configuration effectively meets oil cooling requirements while minimizing pressure drop and fan air losses, improving fuel economy and engine efficiency by eliminating the need for additional cooling elements and reducing specific fuel consumption.
Implementation Method 1
heat exchangers within at least some of the fan outlet guide vanes
Data Source
AI summary
A gas turbine engine hybrid outer guide vane heat exchanger includes a circular row of fan outlet guide vanes, at least some of the fan outlet guide vanes being networked guide vane heat exchangers including heat exchangers within fan outlet guide vanes and guide vane heat exchangers fluidly interconnected both in series and in parallel. Group may include three or more of the guide vane heat exchangers fluidly connected both in series and in parallel. Two or more serial sets of the networked guide vane heat exchangers in the hybrid group may each include two or more of guide vane heat exchangers connected in series and two or more serial sets connected in parallel. First and second groups of the networked guide vane heat exchangers may include first and second groups for cooling engine lubrication system and/or integrated drive generator.