Axial Fan Impeller Hub Structure to Cut Mass and Air Recirculation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional axial fan wheels for motor vehicle radiators face inefficiencies due to increased power consumption and fuel usage caused by rotating mass and contamination issues with mechanisms integrated into the fan hub, which also obstruct airflow and reduce negative pressure.

Innovation Solution

An axial fan wheel design featuring a hub with through recesses and a non-rotatable element to maintain pressure difference, reducing rotating mass and preventing air recirculation, while allowing for efficient torque transmission and maintaining pressure without contributing to the hub's moment of inertia.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If a mechanism with moving parts is integrated into the rotating fan hub to control airflow, then airflow control is improved, but the rotating mass increases leading to higher power consumption

Engineering Contradiction:
Improveairflow controlVSAvoidpower consumption
Core Design Contradiction:
Ease of operationVSUse of energy by moving object

Solution Approach 1:

The invention extracts the airflow control function from the rotating fan hub and relocates it to a stationary screen arrangement. The screen is positioned in the airflow path between the impeller blades and the hub, separating the rotation function (performed by the hub and blades) from the airflow control function (performed by the stationary screen). This eliminates the need for moving parts in the hub while maintaining effective airflow management.

Inventive Principle:
Principle #2Taking out (Extraction)

2Ease of operation

If a mechanism with moving parts is integrated into the fan hub, then airflow control is improved, but the mechanism becomes blocked by contamination in the airflow

Engineering Contradiction:
Improveairflow controlVSAvoidcontamination resistance
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The invention removes the airflow control mechanism from the rotating hub assembly and places it in a stationary position within the airflow path. This stationary screen arrangement has no moving parts that can wear or become blocked, significantly improving reliability and resistance to contamination while maintaining airflow control functionality.

Inventive Principle:
Principle #2Taking out (Extraction)

3Use of energy by moving object

If the hub is made open to reduce rotating mass, then power consumption decreases, but the negative pressure built up on the radiator side is reduced

Engineering Contradiction:
Improvepower consumptionVSAvoidnegative pressure
Core Design Contradiction:
Use of energy by moving objectVSStress or pressure

Solution Approach 1:

The invention applies local quality by implementing a screen arrangement with specific aperture patterns in critical areas where airflow control is needed, while allowing other areas of the hub to remain open for weight reduction. The screen is positioned strategically in the airflow path to maintain negative pressure without requiring the entire hub to be solid, thus balancing weight reduction with pressure maintenance.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The stationary screen arrangement acts as an intermediary element between the impeller blades and the hub opening. It mediates the airflow, directing it appropriately while allowing the hub to remain open for weight reduction. The screen maintains the necessary negative pressure by controlling airflow paths without requiring a solid hub structure.

Inventive Principle:
Principle #24Intermediary (Mediator)

4Ease of operation

If a mechanism is integrated into the fan hub, then airflow control is improved, but the device complexity increases

Engineering Contradiction:
Improveairflow controlVSAvoidstructural complexity
Core Design Contradiction:
Ease of operationVSDevice complexity

Solution Approach 1:

The invention extracts the airflow control function from the complex rotating hub mechanism and replaces it with a simple stationary screen arrangement. This screen can be a single component with aperture patterns, eliminating the need for moving parts, actuators, and control mechanisms, thus significantly reducing device complexity while maintaining airflow control.

Inventive Principle:
Principle #2Taking out (Extraction)

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 design enhances energy efficiency by reducing power consumption and fuel usage while maintaining pressure difference and preventing air recirculation, ensuring effective airflow without increasing the hub's moment of inertia.

Implementation Method 1

The rotating mass of the hub can be reduced due to the through-holes, thus decreasing the required drive power, especially at varying speeds.

Methodology Applied
Scientific EffectMass reduction through material removal:

Implementation Method 2

at least one element arranged within the rim ring and fixed to the axial fan wheel is designed to maintain a pressure differential in the axial direction when the axial fan wheel is rotating

Methodology Applied
Scientific EffectPressure differential maintenance: Pressure Gradient

Implementation Method 3

The at least one element can prevent pressure equalization or pressure attenuation of the air via the passage openings. This at least one element can be designed without or without a significant contribution to the rotating mass of the hub

Methodology Applied
Scientific EffectAir recirculation prevention:

Implementation Method 4

connecting surfaces along an outer circumference of the hub for torque transmission to the inner ring and the rim ring

Methodology Applied
Scientific EffectFriction: Friction

Implementation Method 5

connecting surfaces along an outer circumference of the hub for torque transmission to the inner ring and the rim ring

Methodology Applied
Scientific EffectTorque transmission: Torque

Implementation Method 6

an axial fan wheel is, for example, arranged behind the radiator in the direction of airflow to create a negative pressure

Methodology Applied
Scientific EffectNegative pressure generation: Pressure Gradient

Implementation Method 7

The impeller blades can extend radially from the ring outside of it. The impeller blades can drive an airflow.

Methodology Applied
Scientific EffectAirflow generation:

Data Source

PatentEP3892860B1Axial fan impeller
Publication Date: 2023.09.06 MAN TRUCK & BUS SE
  • EP3892860B1 patent drawingFigure 1
  • EP3892860B1 patent drawingFigure 2
  • EP3892860B1 patent drawingFigure 3

AI summary

An axial fan wheel (102), particularly for the radiator of a motor vehicle engine, is described. The axial fan wheel (102) comprises a rim ring (108) with a plurality of impeller blades (104); and a hub (112) with an inner ring (114) connected or connectable to a drive shaft and connecting surfaces along an outer circumference (118) of the hub (112) for torque transmission to the inner ring (114) and the rim ring (108). The hub (112) has through-holes (120) between the inner ring (114) and the outer circumference (118), the inner ring (114) being arranged outside a plane of rotation defined by the connecting surfaces.At least one element (117; 126) arranged within the ring of the axial fan wheel (108) in a rotationally fixed manner is designed to maintain a pressure difference in the axial direction when the axial fan wheel (102) is rotating, wherein the at least one element (126) closes the passage recesses (120) between the inner ring (114) and the outer circumference (118) and/or the interior of the ring of the axial fan wheel (108).