Stepped-louvre heating, ventilating and air conditioning unit used in high-velocity, low speed fan
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional high-volume, low-speed (HVLS) fans have a 'dead' air area with minimal air movement near the centerline, limiting airflow effectiveness and coverage, while high-speed fans consume more energy and have limited area impact.
Innovation Solution
A stepped leading edge design on fan blades and a stepped-louvre configuration in the air handling manifold create turbulent airflow, increasing velocity and coverage, with the leading edge stepped down from the hub in a 3:2:1 ratio and adjustable louvres to control air discharge.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If traditional HVLS fans are used, then energy consumption is low, but dead air areas with minimal air movement occur near the centerline
Solution Approach 1:
The fan blade leading edge is segmented into multiple steps (first step, second step, third step) with different heights, creating distinct airflow paths at different levels. This segmentation allows the blade to generate turbulent airflow that penetrates dead air zones while maintaining the low energy consumption of HVLS fans.
Solution Approach 2:
The leading edge of the fan blade has non-uniform height distribution with specific steps positioned at predetermined ratios (e.g., 3:2:1) along the blade span. This local variation in blade geometry creates targeted turbulent airflow in specific regions, particularly addressing dead air areas near the centerline while preserving overall system energy efficiency.
2Speed
If high-speed fans are used, then airflow velocity increases, but energy consumption increases dramatically
Solution Approach 1:
The stepped leading edge design creates mechanical turbulence and vortex formation as air passes over the different step heights. This turbulent flow generation mechanism increases effective airflow velocity and mixing without requiring increased motor speed, thereby avoiding the dramatic energy consumption increase associated with high-speed fans.
Solution Approach 2:
The invention changes the geometric parameters of the fan blade (leading edge height, step positions, step ratios) rather than changing the operating speed parameter. This allows velocity enhancement through flow structure modification while maintaining the low-speed, low-energy operational regime of HVLS fans.
3Speed
If stepped leading edge design is implemented, then turbulent airflow and velocity increase, but device complexity increases
Solution Approach 1:
The blade leading edge is divided into discrete steps (typically three steps) that can be manufactured as separate components or formed through controlled molding. This segmentation approach achieves complex flow control functionality while maintaining relatively simple manufacturing processes and assembly procedures.
Solution Approach 2:
The stepped leading edge introduces controlled asymmetry in the blade geometry, with steps positioned at predetermined ratios (such as 3:2:1) along the blade span. This asymmetric design creates the desired turbulent flow patterns and velocity enhancement while following systematic design rules that prevent excessive complexity.
4Productivity
If stepped louvres are used in manifold, then air distribution balance improves, but manufacturing complexity increases
Solution Approach 1:
The manifold outlet is divided into multiple louvres with stepped configurations, where each louver has different step heights and angles. This segmentation allows independent optimization of airflow from different manifold regions, improving overall distribution balance while using standardized manufacturing techniques for each louver element.
Solution Approach 2:
Different sections of the manifold have louvres with locally optimized step configurations tailored to specific airflow requirements. This local customization of louver geometry achieves balanced air distribution across the entire manifold output while following systematic design patterns that facilitate manufacturing.
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 enhances airflow velocity and coverage, reducing 'dead' spots and extending air movement range, providing a more balanced and efficient distribution of cooled or heated air, improving comfort and energy efficiency.
Implementation Method 1
the leading edge has regular steps at a predetermined ratio configured to create turbulent airflow
Data Source
AI summary
A fan blade apparatus for use in a high-volume, low-speed fan wherein the fan blade includes a body portion, a leading edge portion and a trailing portion. The leading edge portion of the fan blade includes a series of steps extending along the length of the leading edge. The stepped configuration creates turbulent air flow when the electric motor rotates in the intended direction. A manifold including a stepped louvre to control airflow along a fan blade. A fan blade for use in a high-volume, low-speed fan, wherein the fan blade includes a body portion, a leading edge portion and a trailing portion. The leading edge portion of the fan blade includes a series of steps extending along the length of the leading edge. The fan distributes airflow from the manifold.