Heat Pump Dryer Condenser Bypass for Thermal Load Balance

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing cooling systems for heat pump dryers face challenges in maintaining thermal load balance due to insufficient heat removal through the evaporator, leading to increased complexity and cost when using fans or additional condensers to enhance heat exchange.

Innovation Solution

A by-pass system controlled by an electro-valve directs the refrigerant flow through the condenser, allowing for adjustable heat exchange by diverting the flow through either the entire condenser or a by-pass, reducing complexity and cost.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If a fan is used to blow air on the condenser to increase heat exchange, then the thermal load balance is improved, but the system complexity and cost increase

Engineering Contradiction:
Improvethermal load balanceVSAvoidsystem complexity
Core Design Contradiction:
TemperatureVSDevice complexity

Solution Approach 1:

The patent applies a three-way valve to dynamically redirect refrigerant flow through different paths (full condenser, partial condenser, or bypass) based on thermal load requirements. This dynamic flow control allows the system to adjust heat exchange capacity without adding fans or additional condensers, resolving the contradiction between thermal balance performance and system complexity

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The invention changes the refrigerant flow parameters (flow rate, distribution ratio) through the condenser using the three-way valve to achieve different heat exchange levels. By controlling the valve position, the system can optimize thermal load balance without increasing device complexity, as the same condenser structure serves multiple operational modes

Inventive Principle:
Principle #35Parameter changes

2Temperature

If an additional condenser (post-condenser) is used to increase heat exchange, then the thermal load balance is improved, but the system complexity and cost increase

Engineering Contradiction:
Improvethermal load balanceVSAvoidsystem complexity
Core Design Contradiction:
TemperatureVSDevice complexity

Solution Approach 1:

The three-way valve enables dynamic configuration of the refrigerant path, allowing the existing condenser to operate in different modes (full engagement, partial engagement, or bypass). This eliminates the need for an additional post-condenser while maintaining the ability to adjust heat exchange capacity according to thermal load demands

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The invention makes the existing condenser multi-functional by allowing it to operate at different heat exchange levels through refrigerant flow redirection. The same condenser structure serves as full condenser, partial condenser, or bypass element, eliminating the need for additional condensing components and reducing system complexity

Inventive Principle:
Principle #6Universality (Multi-functionality)

3Device complexity

If the electro-valve directs refrigerant flow through the by-pass, then the heat exchange is reduced, but the system complexity is reduced

Engineering Contradiction:
Improvesystem complexityVSAvoidheat exchange
Core Design Contradiction:
Device complexityVSTemperature

Solution Approach 1:

The three-way valve provides dynamic control over refrigerant flow distribution, enabling the system to switch between high heat exchange mode (through condenser) and low heat exchange mode (through bypass) based on operational requirements. This dynamic capability allows the system to reduce complexity by eliminating additional components while maintaining thermal balance control through flow path selection

Inventive Principle:
Principle #15Dynamics

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 enables efficient control of thermal balance by adjusting condenser heat exchange without the need for additional components, reducing system complexity and cost while maintaining energy efficiency.

Implementation Method 1

upstream the condenser in the refrigeration circuit 22 it is placed a three-way valve 32 which can direct the flow of refrigerant towards the condenser or toward a by-bass pipe 34

Methodology Applied
Scientific EffectFluid flow direction control: Valve

Implementation Method 2

the heat released by the condenser of the cooling system

Methodology Applied
Scientific EffectHeat exchange: Heat Exchanger

Implementation Method 3

heat exchange through the condenser has to be increased or reduced according to the working condition of the drier

Methodology Applied
Scientific EffectThermal conduction: Conduction (thermal)

Implementation Method 4

The cooling system is not only used to remove water by condensation on evaporator surface from the warm air downstream the drier drum

Methodology Applied
Scientific EffectHeat exchange: Heat Exchanger

Implementation Method 5

remove water by condensation on evaporator surface

Methodology Applied
Scientific EffectCondensation: Condensation

Implementation Method 6

a refrigeration circuit including a compressor, a condenser and an evaporator

Methodology Applied
Scientific EffectGas compression: Compression

Data Source

PatentEP2703551B1Cooling system for a heat pump drier and heat pump drier using such cooling system
Publication Date: 2015.01.28 WHIRLPOOL CORP
  • EP2703551B1 patent drawingFigure 1~3
  • EP2703551B1 patent drawingFigure 2
  • EP2703551B1 patent drawingFigure 4

AI summary

A cooling system for a heat pump drier comprises a refrigeration circuit including a compressor, a condenser and an evaporator. The refrigeration circuit comprises a three-way valve upstream the condenser and adapted to by-bass partially the condenser at a predetermined distance from the inlet point.