Dishwasher Airflow Guiding for Heat Pump Cold Air Reflection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

In heat pump dishwashers, the reflection of cold air at the rear of the dishwasher decreases the heat transfer capacity of the first heat exchanger, leading to increased energy consumption for heating water.

Innovation Solution

A guiding member is introduced between the washing tub and the body, which can shift between closed and open positions to direct air from the first heat exchanger either to the lower side of the body for discharge or to the drying duct, preventing cold air from reaching the rear wall and enhancing air flow and heat transfer efficiency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the rear side of the dishwasher is closed to contain the structure, then structural integrity is maintained, but cold air reflects and condenses at the rear wall, decreasing heat transfer capacity of the first heat exchanger and increasing energy consumption

Engineering Contradiction:
Improvestructural integrityVSAvoidenergy consumption
Core Design Contradiction:
ReliabilityVSUse of energy by moving object

Solution Approach 1:

A guiding member is introduced as an intermediary component between the first heat exchanger and the rear wall. This guiding member directs the flow of cooled air away from the rear wall, preventing reflection and condensation. The intermediary structure resolves the contradiction by maintaining the closed rear wall for structural integrity while eliminating the harmful air flow pattern that causes energy loss.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Loss of energy

If the first heat exchanger absorbs heat from ambient air to support water heating, then energy efficiency is improved, but cooled air reaches the rear wall and reflects back, reducing heat transfer capacity and requiring more energy

Engineering Contradiction:
Improveenergy loss in heat transferVSAvoidheat transfer capacity
Core Design Contradiction:
Loss of energyVSProductivity

Solution Approach 1:

The guiding member creates a dynamic air flow management system that actively directs cooled air away from the rear wall. This dynamic control of air flow patterns prevents the static problem of air reflection and condensation, maintaining optimal heat transfer capacity of the first heat exchanger and reducing energy loss in the heat pump system.

Inventive Principle:
Principle #15Dynamics

3Productivity

If cold air is discharged from the rear side of the dishwasher, then heat transfer performance is maintained, but the rear wall remains closed requiring additional air passage provisions

Engineering Contradiction:
Improveheat transfer performanceVSAvoidair passage configuration
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

The guiding member merges the air discharge function with the existing closed rear wall structure. Instead of requiring separate air passage provisions that would increase device complexity, the guiding member integrates the air flow direction control into the existing structural framework, maintaining heat transfer performance while avoiding additional structural complexity.

Inventive Principle:
Principle #5Merging (Combining)

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 increases the heat transfer capacity of the first heat exchanger, improving the energy efficiency of the heat pump and enhancing drying performance by preventing cold air reflection and promoting dehumidification in the drying duct.

Implementation Method 1

The first heat exchanger draws the heat of the ambient air and transfers it to the second heat exchanger

Methodology Applied
Scientific EffectHeat transfer: Conduction (thermal)

Implementation Method 2

The compressor is in fluid connection to the first heat exchanger and the second heat exchanger, and performs the refrigerant cycle

Methodology Applied
Scientific EffectCompression: Compression

Implementation Method 3

The second heat exchanger transfers the heat received to the washing water

Methodology Applied
Scientific EffectHeat transfer: Conduction (thermal)

Implementation Method 4

The ambient air is delivered onto the first heat exchanger by means of a fan

Methodology Applied
Scientific EffectForced convection: Forced Convection

Data Source

PatentEP3982811B1A dishwasher comprising a heat pump
Publication Date: 2023.09.06 ARCELIK AS
  • EP3982811B1 patent drawingFigure 1
  • EP3982811B1 patent drawingFigure 2
  • EP3982811B1 patent drawingFigure 3

AI summary

The present invention relates to a dishwasher (1) comprising a body (2), a washing tub (3) which is disposed in the body (2) and wherein the washing process is performed with the water taken from the mains line; a drying duct (4) which is provided on the body (2) and which provides the circulation of the humid air in the washing tub (3) by taking the same out of the washing tub (3) after the washing process, thus enabling the washed items to be dried; a heat pump (5) which is disposed under the washing tub (3), having a first heat exchanger (6) enabling the water to be used in the washing step to be heated by drawing heat from the environment, a second heat exchanger (7) transferring the heat received from the first heat exchanger (6) to the washing water and a compressor (8) fluidly connected to the first heat exchanger (6) and the second heat exchanger (7) so as to realize the refrigerant cycle; and at least one fan (9) which enables the outer environment air to be delivered onto the first heat exchanger (6).