Aircraft Mixing Device Icing Prevention
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Aircraft air-conditioning systems face challenges in preventing the accumulation of ice or snow in mixing devices due to the introduction of cold fresh air, which can lead to icing issues in the mixing chamber and ducts, affecting the air-conditioning efficiency and safety.
Innovation Solution
A mixing device with a first recirculation air supply line that includes a heat transfer portion connected to the mixing chamber wall at risk of icing, utilizing warm recirculation air to prevent ice formation by transferring thermal energy, thereby reducing the need for additional heating and maintaining energy efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If cold fresh air is introduced to the mixing device for air-conditioning, then the cooling performance is improved, but the risk of ice accumulation in the mixing chamber and ducts increases
Solution Approach 1:
The patent applies preliminary anti-action by introducing warm recirculation air through a heating element positioned at the mixing chamber wall before ice can form. This preventive heating counteracts the cooling effect of cold fresh air on the mixing chamber wall, maintaining the wall temperature above freezing point while allowing cold air to be mixed for cooling performance.
Solution Approach 2:
The patent uses warm recirculation air as an intermediary substance to transfer thermal energy to the mixing chamber wall. This intermediary warm air flow, controlled by a trim valve, mediates between the cold fresh air and the mixing chamber wall, preventing direct contact between cold air and the wall surface that would cause icing.
2Object-affected harmful factors
If additional heating measures are implemented to prevent icing, then the ice accumulation risk is reduced, but the energy efficiency of the air-conditioning system deteriorates
Solution Approach 1:
The patent applies self-service by using the system's own recirculation air, which is already warm from the air-conditioning process, to heat the mixing chamber wall. Instead of introducing external energy sources, the system repurposes its internal warm air flow, controlled by a trim valve, to prevent icing, thereby maintaining energy efficiency while reducing ice accumulation risk.
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 solution effectively prevents the formation of thick ice layers on the mixing chamber wall by using the thermal energy from recirculation air, allowing for efficient operation and maintaining high mixing quality without the need for additional thermal energy, thus addressing the icing issue in aircraft air-conditioning systems.
Implementation Method 1
The first recirculation air supply line (14) has a heat transfer portion (14b) which is thermoconductively connected to an area (24) of a wall (22) delimiting the mixing chamber (18) that is at risk of icing
Data Source
AI summary
A mixing device that is particularly suitable for use in an aircraft air-conditioning system comprising a cold air supply line adapted to supply cold air to the mixing device. A first recirculation air supply line is adapted to supply recirculation air to the mixing device. A mixing chamber is connected to the cold air supply line and the first recirculation air supply line and is adapted to supply the cold air supplied to the mixing device via the cold air supply line with the recirculation air supplied to the mixing device via the first recirculation air supply line. The first recirculation air supply line has a heat transfer portion which is thermoconductively connected to an area of a wall delimiting the mixing chamber that is at risk of icing.