Reflex Camber Turbine Rotor Shielding Core from Flow

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Vertical axis wind turbines, particularly Savonius type, face challenges with supporting large thin blades, which leads to unwanted drag and turbulence, and inefficiencies due to the need for heavy bracing and large end caps.

Innovation Solution

A turbine rotor assembly with an unbroken perimeter formed by three reflex camber surfaces, where the surfaces are joined end to end to create a shielded rotor core, allowing bearings, supports, and other elements to be placed out of the flow of the driving fluid, reducing drag and turbulence.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Area of moving object

If large thin blades are used in Savonius turbines, then blade area and power generation capacity are improved, but structural stability deteriorates requiring heavy bracing and large end caps

Engineering Contradiction:

Improveblade areaVSAvoidstructural stability

Core Design Contradiction:

Area of moving objectVSStrength

Solution Approach 1:

The rotor is divided into three separate reflex camber surfaces that are joined end-to-end, creating a modular structure. Each surface can be independently supported by the rotor core, distributing structural loads and eliminating the need for heavy end caps while maintaining large blade area for power generation.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The reflex camber surfaces are nested around a central rotor core, with each surface attached to the core at its base. This nested configuration allows the core to provide internal support to all surfaces, eliminating the need for external bracing and large end caps, while maintaining structural integrity of large thin blades.

Inventive Principle:

Principle #7Nested doll (Nesting)

2Strength

If heavy bracing and large end caps are added to support blades, then structural stability is improved, but drag and turbulence increase

Engineering Contradiction:

Improvestructural stabilityVSAvoiddrag and turbulence

Core Design Contradiction:

StrengthVSObject-generated harmful factors

Solution Approach 1:

The harmful elements (heavy bracing and large end caps) are extracted from the design by using the nested rotor core configuration. The core provides necessary structural support internally, eliminating external bracing elements that would create drag and turbulence, thus maintaining structural stability without harmful factors.

Inventive Principle:

Principle #2Taking out (Extraction)

3Ease of operation

If bearings and supports are placed in the flow path, then structural support is provided, but drag and turbulence are increased

Engineering Contradiction:

Improvestructural supportVSAvoiddrag and turbulence

Core Design Contradiction:

Ease of operationVSObject-generated harmful factors

Solution Approach 1:

Bearings and support elements are nested within the rotor core, placing them outside the flow path of the reflex camber surfaces. This internal nesting provides necessary structural support while eliminating interference with fluid flow, thus reducing drag and turbulence while maintaining ease of operation.

Inventive Principle:

Principle #7Nested doll (Nesting)

4Ease of manufacture

If traditional Savonius rotor design is used, then manufacturing simplicity is maintained, but efficiency is reduced due to drag from supporting elements

Engineering Contradiction:

Improvemanufacturing simplicityVSAvoidturbine efficiency

Core Design Contradiction:

Ease of manufactureVSProductivity

Solution Approach 1:

The rotor is segmented into three independent reflex camber surfaces joined at their ends, forming a continuous perimeter. This segmentation allows for simpler manufacturing of individual surfaces while the end-to-end joining eliminates gaps and reduces drag, improving efficiency without sacrificing manufacturing simplicity.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The reflex camber surfaces are designed with curved aerodynamic profiles that follow the flow of the driving fluid. This curvature optimization improves efficiency by reducing turbulence and drag, while the surfaces can still be manufactured using standard forming techniques, maintaining ease of manufacture.

Inventive Principle:

Principle #14Spheroidality (Curvature)

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

This design enhances durability and efficiency by minimizing drag and turbulence, allowing for improved performance and reduced rotational inertia, enabling quicker response to wind speed changes and eliminating the need for large end caps.

Implementation Method 1

each reflex camber surface having an aerodynamic shape for improved efficiency

Methodology Applied

Scientific EffectAerodynamic lift: Aerofoil

Implementation Method 2

The difference in drag on one half of the rotor from the other half of the rotor causes the rotor to spin in the wind

Methodology Applied

Scientific EffectDrag: Drag

Implementation Method 3

eliminating undesired drag and turbulence which would otherwise be created by those elements

Methodology Applied

Scientific EffectTurbulence: Turbulence

Data Source

PatentUS9494136B1Reflex camber surfaces for turbines

Publication Date: 2016.11.15 EDMISTON DANIEL

AI summary

A turbine rotor assembly having a rotor core formed by three reflex camber surfaces disposed symmetrically about an axis, each reflex camber surface being identical and having an aerodynamic shape producing positive torque through a large portion of its upwind travel while rotating about the axis. The trailing edge of each reflex camber surface joined to the leading edge of the adjacent reflex camber surface creating an envelope shielding the rotor core from the fluid driving the rotor.