Variable Nozzle Unit Sealing for Supercharger Efficiency
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Variable-capacity superchargers face challenges in reducing size while increasing output for diesel engines with low fuel and environmental load, and existing solutions do not adequately improve supercharging efficiency.
Innovation Solution
A variable nozzle unit is introduced, featuring a first nozzle ring with support holes, a second nozzle ring with corresponding through-holes, and seal members between the turbine scroll channel and turbine wheel, which prevents exhaust gas leakage and enhances flow control through the variable nozzles, increasing supercharging efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a seal cover is provided at the rear surface side of the second nozzle ring to prevent exhaust gas leakage, then supercharging efficiency is improved, but device complexity increases
Solution Approach 1:
The patent extracts the sealing function from a separate seal cover component and integrates it directly into the second nozzle ring structure. The second nozzle ring itself is designed with sealing surfaces and features that prevent exhaust gas leakage, eliminating the need for an additional seal cover component while maintaining sealing effectiveness.
Solution Approach 2:
The patent combines multiple functions into the second nozzle ring: it serves as both the structural component that positions the variable nozzles and as the sealing element that prevents exhaust gas leakage. By merging the nozzle support function and sealing function into a single integrated component, the overall device complexity is reduced.
2Power
If the variable nozzle unit is optimized to improve supercharging efficiency, then output increases, but the size reduction goal is compromised
Solution Approach 1:
The patent employs variable nozzles that can dynamically adjust their opening area to optimize exhaust gas flow characteristics under different operating conditions. This dynamic adjustment capability allows the system to achieve high output performance without requiring a larger overall size, as the same physical space is utilized more efficiently through active flow control.
Solution Approach 2:
The patent changes the flow parameters of exhaust gas by adjusting the nozzle opening area, which directly affects the mass flow rate and velocity of exhaust gas entering the turbine wheel. By optimizing these parameters, the system achieves higher power output from a compact size, as parameter optimization allows better utilization of available space and resources.
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 improves supercharging efficiency by preventing exhaust gas leakage and optimizing flow rates through the nozzles, allowing for increased output and reduced size in variable-capacity superchargers.
Implementation Method 1
The plurality of variable nozzles are synchronized and rotated in an opening direction, and thereby a channel area of an exhaust gas supplied to the turbine wheel side can be increased
Implementation Method 2
a seal cover is provided at a rear surface side of the second nozzle ring which is opposite to a surface facing the first nozzle ring. Thus, a constitution for preventing leakage of the exhaust gas from the turbine scroll channel to an outlet side of the turbine wheel is suggested
Data Source
AI summary
A variable nozzle unit in a variable-capacity supercharger includes: a first nozzle ring disposed in a turbine housing and formed with a plurality of first support holes; a second nozzle ring disposed to face the first nozzle ring and formed with a plurality of second support holes that are through-holes corresponding to the first support holes; a plurality of variable nozzles supported rotatably by the first and second nozzle rings; and a plurality of seal members disposed between a turbine scroll channel and a turbine wheel side. The variable nozzles include first nozzle shafts that are rotatably supported by the first support holes, and second nozzle shafts that are rotatably supported by the second support holes, and a first seal member included in the plurality of seal members is provided at the turbine wheel side relative to the second support holes.