Folding Propeller Blade Geometry for Low-Drag Sailing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing propellers for sailing vehicles face challenges in achieving high efficiency during thrusting and generating operations while minimizing resistance when folded, and are often complex, expensive, and require significant space, failing to optimize performance across different sailing conditions.
Innovation Solution
A propeller with folding blades that form a continuous spindle shape when closed, minimizing friction and turbulence, and a mechanism that allows adjustable pitch and folding without mechanical complexity, using a gear system to transition between open and closed positions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If a propeller with high pitch and diameter is used to maximize efficiency in propulsion and regeneration, then propulsion performance and energy regeneration are improved, but friction resistance increases significantly during sailing
Solution Approach 1:
The propeller blades are designed to be movable rather than fixed, allowing them to change their configuration dynamically. The blades can rotate around an axis to transition between open and closed positions, enabling the propeller to adapt its pitch angle based on sailing conditions. This dynamic adjustment allows optimization of propulsion efficiency when needed while minimizing friction resistance during sailing phases
Solution Approach 2:
The invention changes the geometric parameters of the propeller blades by allowing rotation around an axis. This enables the pitch angle of the blades to be modified, transforming the propeller from a fixed-parameter design to a variable-parameter system. The blades can be positioned at different angles relative to the water flow, changing the effective pitch diameter and optimizing performance for different operational modes
2Object-affected harmful factors
If a small propeller is used to reduce friction during sailing, then friction resistance is reduced, but propulsion performance and regeneration capability become insufficient
Solution Approach 1:
The propeller employs movable blades that can rotate between open and closed positions. During sailing, the blades are positioned in the closed configuration to minimize friction, while during propulsion or regeneration phases, they open to provide adequate pitch for effective thrust generation. This dynamic reconfiguration allows a single propeller to serve multiple functions without compromising performance
3Productivity
If propeller blades are designed with significant twist and elongation to maximize efficiency, then propulsion efficiency is improved, but the complexity of the folding mechanism increases
Solution Approach 1:
The propeller is divided into discrete blade segments that can independently rotate around their respective axes. Each blade is connected to the hub through a folding mechanism that allows it to pivot between open and closed positions. This segmentation enables the complex function of pitch adjustment to be achieved through simple, modular rotational joints rather than a single complex mechanism
Solution Approach 2:
Instead of using a complex mechanism to adjust the pitch of each blade individually, the invention inverts the approach by using a simpler folding mechanism that rotates the entire blade assembly. The pitch adjustment is achieved through the rotational position of the blade relative to the hub, rather than through complex pitch 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
The propeller achieves high efficiency during propulsion and regeneration with minimal resistance, facilitating easy cleaning and maintenance, and reduces energy consumption by optimizing blade positioning and pitch adjustment.
Implementation Method 1
propellers with blades folding around a secant or twisting axis typically located at about 90 degrees relative to the axis of the propeller that open by centrifugal force or inertia
Implementation Method 2
propellers with blades folding around a secant or twisting axis typically located at about 90 degrees relative to the axis of the propeller that open by centrifugal force or inertia
Data Source
AI summary
A propeller with folding blades for the propulsion of a mobile vehicle inside a fluid is provided having a movement mechanism rotatable around a central rotation axis of the propeller; and a plurality of blades. Each blade has a root end connected to the movement mechanism by a gear to allow the movement of the blade from an opening position to a closed position and vice versa, wherein in the closed position the plurality of blades are configured to form a continuous solid in the form of a spindle wherein a leading edge of a first blade (S′) is configured to osculate a trailing edge of a second blade following the first blade (S′) in such a way as to form a continuous surface between the first blade (S′) and the second blade (S″).