Bi-Directional Radial Fan Blades for Hydroelectric Machine Cooling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing radial fans for hydroelectric machines are limited to cooling in a single rotational direction, failing to effectively cool motor-generators in both pump and turbine modes, and lack efficiency and noise reduction capabilities.
Innovation Solution
A bi-directional radial fan with symmetrical, tear-drop shaped blades and sealing components that rotate independently of the motor-generator's direction, ensuring consistent air flow and pressure generation, reducing pressure loss and delamination.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a radial fan with straight blades is used, then the structure is simple and easy to manufacture, but the static pressure generation and efficiency are poor
Solution Approach 1:
The patent applies curvature by replacing straight blade edges with curved, rounded profiles. The blades feature a rounded leading edge and a curved suction surface that transitions smoothly to the trailing edge. This curvature optimizes the airflow path around the blades, improving static pressure generation and fan efficiency while maintaining manufacturability through standard forming processes.
2Device complexity
If a single-direction radial fan is used, then the structure is simple, but it cannot cool effectively in both pump and turbine modes
Solution Approach 1:
The patent employs asymmetry in the blade cross-sectional profile, where the pressure surface and suction surface have different curvatures and shapes. This asymmetric airfoil section is designed to maintain effective cooling in both rotation directions. The specific asymmetric profile optimizes airflow attachment and pressure distribution regardless of rotation direction, enabling the fan to cool effectively in both pump and turbine modes without requiring separate fans for each direction.
3Device complexity
If cooling is not provided in both modes, then the system is simpler, but the motor-generator cannot operate in both pump and turbine modes
Solution Approach 1:
The radial fan is designed as a universal cooling device that performs the same cooling function in both pump and turbine modes. The blade geometry, including the rounded leading edge, curved suction surface, and asymmetric airfoil profile, is specifically optimized to maintain effective cooling regardless of rotation direction. This multi-functional design ensures the motor-generator can reliably operate in both modes with a single cooling system.
4Ease of manufacture
If straight blade edges are used, then manufacturing is easier, but pressure loss and delamination occur
Solution Approach 1:
The patent applies curvature by replacing straight blade edges with curved, rounded profiles. The blades feature a rounded leading edge and a curved suction surface that transitions smoothly to the trailing edge. This curvature optimizes the airflow path around the blades, improving static pressure generation and fan efficiency while maintaining manufacturability through standard forming processes.
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 bi-directional fan achieves higher static pressure generation, improved efficiency, and reduced power consumption, enhancing cooling performance and power generation capabilities in both pump and turbine modes.
Implementation Method 1
radial fans according to the prior art are limited by their ability to rotate in one direction only, and thereby cool effectively in a single rotational direction
Implementation Method 2
Because of the symmetrical profile of each blade, it has been found that a fan of a hydroelectric machine according to the present invention has a considerably better performance with respect to static pressure generation and efficiency
Data Source
Figure 1
Figure 2~4
Figure 5
AI summary
A radial fan comprising: a plurality of blades rotatable about an axis of rotation and extending radially from the axis of rotation; characterised in that each of the blades has a transverse profile that is symmetrical about a radial line of symmetry extending through the blade, at least a portion of the profile of each blade being curved.