Indoor Air Outlet Guide Geometry for Uniform AC Airflow

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Solution Overview

Problem

Existing air-conditioning-apparatus indoor units face issues with non-uniform airflow distribution, leading to dew formation and smudging due to low airflow speed at the long-side ends of air outlets, which increases draft resistance and power consumption.

Innovation Solution

The air-conditioning-apparatus indoor unit incorporates deflection guides with a specific shape that redirects airflow from the ends towards the center, increasing airflow speed uniformly across the outlet area, preventing dew formation and smudging, while maintaining a shorter deflection guide length to reduce draft resistance and power consumption.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If the deflection guide is extended in the long-side direction of the air outlet to control airflow at the ends, then the airflow speed distribution becomes more uniform, but the draft resistance in the air passage increases and power consumption increases

Engineering Contradiction:
Improveairflow speed distribution uniformityVSAvoidpower consumption
Core Design Contradiction:
Manufacturing precisionVSUse of energy by moving object

Solution Approach 1:

The deflection guide is designed with a specific shape that provides localized airflow control at the ends of the air outlet. By concentrating the deflection function at strategic locations rather than extending the guide throughout the entire long-side direction, the patent achieves improved airflow speed distribution uniformity while limiting the increase in draft resistance and power consumption.

Inventive Principle:
Principle #3Local quality

2Reliability

If the deflection guide length is increased to control airflow at the long-side ends, then dew formation and smudging are prevented, but the device complexity and space requirements increase

Engineering Contradiction:
Improveprevention of dew formation and smudgingVSAvoiddeflection guide structure
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The deflection guide is designed as a segmented structure that focuses airflow control at the critical end regions of the air outlet. This segmentation allows the patent to prevent dew formation and smudging at the ends where these problems occur most frequently, without requiring a uniformly complex structure throughout the entire air outlet assembly.

Inventive Principle:
Principle #1Segmentation

3Object-affected harmful factors

If the airflow speed at the long-side end is increased to prevent dew formation, then the mixing of humid room air is reduced, but the draft resistance increases

Engineering Contradiction:
Improvedew formationVSAvoiddraft resistance
Core Design Contradiction:
Object-affected harmful factorsVSStress or pressure

Solution Approach 1:

The patent modifies the shape and positioning parameters of the deflection guide to optimize airflow velocity at the long-side ends of the air outlet. By carefully adjusting these geometric parameters, the patent increases airflow speed sufficient to prevent dew formation and reduce mixing with humid room air, while constraining the increase in draft resistance to acceptable levels.

Inventive Principle:
Principle #35Parameter changes

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 solution ensures uniform airflow distribution, preventing dew formation and smudging, while reducing energy consumption by minimizing the length of the deflection guide, resulting in a high-quality, energy-saving air-conditioning system.

Implementation Method 1

Because of the inertia of the airflow, the airflow is not completely redirected, but the speed of the airflow increases in an area near the inner surface of the housing

Methodology Applied
Scientific EffectAirflow inertia: Inertia

Data Source

PatentEP2719968B1Indoor unit for air-conditioner
Publication Date: 2020.07.01 MITSUBISHI ELECTRIC CORP
  • EP2719968B1 patent drawingFigure 1
  • EP2719968B1 patent drawingFigure 2
  • EP2719968B1 patent drawingFigure 3

AI summary

Body air outlets 10d of an air-conditioning-apparatus indoor unit 100 each has a substantially trapezoidal shape in plan view and are each defined by a body-air-outlet outer side wall 10d2, a body-air-outlet inner side wall 10d4, and a pair of body-air-outlet end walls 10d1. The body-air-outlet outer side wall 10d2 is provided with a deflection guide 2 at each of long-side ends thereof. The body-air-outlet end walls 10d1 are each provided with a sloping guide 3. The deflection guide 2 has a deflection-guide upper surface 2a that gradually projects toward the body-air-outlet inner side wall 10d4 in a direction toward a body open face 10e (toward a downstream side) and in a direction toward the central part of the body air outlet 10d. The sloping guide 3 has a sloping-guide upper surface 3a that gradually projects toward the central part of the body air outlet 10d as the sloping guide 3 extends closer to the body open face 10e (toward the downstream side).