Automotive HVAC Air Mixing Duct Layout for Stable Outlet Temperature
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing HVAC modules in automobiles face challenges in effectively mixing cooled and heated air due to differences in flow speed and mixing characteristics, leading to inconsistent temperature control at outlets.
Innovation Solution
An air mixing device with adjacent air ducts forming heated and cooled air passages, featuring a convex curved surface and a tail plate to enhance mixing, along with blocking and vortex-inducing elements to control airflow and temperature.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If cold air flow speed is increased to improve cooling efficiency, then cooling performance is improved, but mixing with hot air becomes difficult and temperature control stability deteriorates
Solution Approach 1:
The air mixing device segments the airflow paths by providing separate inlets for cold air and hot air, with dedicated mixing chambers that allow controlled interaction between the two streams. This segmentation enables independent control of each air stream while ensuring proper mixing, resolving the contradiction between maintaining high cooling efficiency and achieving stable temperature control.
Solution Approach 2:
The device changes the flow parameters by using expansion chambers that increase in cross-sectional area downstream, which reduces the velocity of the high-speed cold air and enhances mixing with hot air. This parameter change (velocity reduction through geometric expansion) maintains cooling efficiency while improving temperature control stability.
2Device complexity
If simple flow control is used to reduce device complexity, then device complexity is reduced, but temperature control precision deteriorates
Solution Approach 1:
The mixing device is segmented into multiple functional sections: cold air inlet, hot air inlet, expansion chambers, and mixing regions. This segmentation allows each section to perform a specific function, achieving precise temperature control through the combined action of simple, well-defined components rather than a single complex mechanism.
Solution Approach 2:
The expansion chamber acts as an intermediary element between the cold air inlet and the mixing region. It mediates the interaction between high-speed cold air and hot air by providing a transition zone where velocity is reduced and mixing is enhanced, achieving precise temperature control without requiring complex active control mechanisms.
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
Efficient mixing of heated and cooled air is achieved, enabling precise temperature control and distribution to various outlets.
Implementation Method 1
A surface of the air duct on a side into which the cooled air is introduced may be formed as a convex curved surface
Data Source
Figure 1
Figure 2
Figure 3
AI summary
An air mixing device for mixing cooled air having passed through a cooling member of an HVAC module and heated air having passed through a heating member according to an embodiment of the present invention includes a plurality of air ducts each forming a heated air passage through which the heated air flows and arranged adjacent to each other. The plurality of the air ducts are arranged adjacent to each other in sequence to form a cooled air passage through which the cooled air flows between the adjacently arranged air ducts, and the air duct is configured such that a portion corresponding to a downstream side of a flow of the cooled air through the cooled air passage is entirely open.