Alternating Vane Centrifugal Fan Impeller Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Centrifugal fans with uniformly sized vanes require excessive manufacturing material, leading to high costs and potential performance degradation when vane length is reduced to save material.
Innovation Solution
The impeller design features alternating first and second vanes of different lengths, with varying gap sizes between adjacent vanes, and inclined portions to optimize static pressure and reduce noise, while minimizing material usage and weight.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the length of all vanes is increased to improve output blowing rate, then performance is improved, but manufacturing material consumption and cost increase
Solution Approach 1:
The patent applies local quality by differentiating vane lengths based on their circumferential positions. Second vanes (at specific angular positions) are made longer to enhance output blowing rate in critical regions, while first vanes are made shorter to reduce overall material consumption. This localized optimization allows the impeller to achieve good airflow performance without requiring all vanes to be uniformly long.
Solution Approach 2:
The patent implements asymmetry by creating an asymmetric vane length distribution around the impeller circumference. Instead of uniform vane lengths, the design uses alternating patterns of longer second vanes and shorter first vanes. This asymmetric configuration optimizes the balance between material usage and airflow generation, allowing the impeller to maintain effective pumping action while reducing total material consumption.
2Quantity of substance
If the length of vanes is reduced to save manufacturing material, then material consumption is reduced, but output blowing rate deteriorates
Solution Approach 1:
The patent applies local quality by differentiating vane lengths based on their circumferential positions. Second vanes (at specific angular positions) are made longer to enhance output blowing rate in critical regions, while first vanes are made shorter to reduce overall material consumption. This localized optimization allows the impeller to achieve good airflow performance without requiring all vanes to be uniformly long.
Solution Approach 2:
The patent applies partial action by providing extended vane length only where it is most needed for airflow generation. The second vanes are made longer than first vanes, creating a pattern where excessive vane length is provided locally at strategic positions rather than uniformly across all vanes. This partial extension maintains output blowing rate while minimizing overall material consumption.
3Ease of manufacture
If uniformly sized gaps are provided between adjacent vanes, then manufacturing is simplified, but static pressure distribution is suboptimal
Solution Approach 1:
The patent implements asymmetry in gap sizing between adjacent vanes. The gaps are designed with different sizes (first gap size and second gap size) in an alternating pattern, rather than being uniformly sized. This asymmetric gap configuration optimizes static pressure distribution across the impeller, allowing for better airflow control and pressure balance while maintaining a relatively simple manufacturing process.
Solution Approach 2:
The patent applies local quality by varying gap sizes at different circumferential positions between adjacent vanes. Instead of uniform gaps, the design uses alternating patterns of larger and smaller gaps (first and second gap sizes) corresponding to the alternating first and second vanes. This localized gap optimization improves static pressure distribution without significantly complicating the manufacturing process.
Data Source
AI summary
A centrifugal fan includes an impeller with a base expanded radially, vanes arranged circumferentially, extending from a radially inner side to a radially outer side, and ends thereof at one axial side being connected to the base, and a ring portion connecting ends of the vanes at the other axial side. The vanes include first vanes and second vanes, when viewed axially, the lengths of the second vanes are larger than the lengths of the first vanes, the first vanes and the second vanes are circumferentially arranged alternatingly. Gaps are provided between radially outer ends of the first vanes and the second vanes that are circumferentially adjacent to each other, and sizes of circumferentially adjacent ones of the gaps are different from each other.