Refrigeration cycle device

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Solution Overview

Problem

The use of a mixed refrigerant containing CF3I and HFO1123 in refrigeration cycle devices leads to disproportionation reactions, which can degrade the performance of the device, as a high ratio of CF3I is required to suppress these reactions but also affects efficiency, while a low ratio is insufficient.

Innovation Solution

A refrigeration cycle device with a refrigerant circuit that includes a compressor, expansion valves, and a refrigerant reservoir, where CF3I is injected from a deeper level within the reservoir to the compressor, utilizing its higher fluid density to suppress disproportionation reactions and maintain performance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Stability of the object's composition

If a high ratio of CF3I is used in the mixed refrigerant to suppress disproportionation reaction, then the stability of refrigerant composition is improved, but the performance of the refrigeration cycle device deteriorates

Engineering Contradiction:
Improvestability of refrigerant compositionVSAvoidperformance of refrigeration cycle device
Core Design Contradiction:
Stability of the object's compositionVSProductivity

Solution Approach 1:

The invention applies local quality by creating a spatial differentiation in CF3I concentration within the refrigerant reservoir. The injection port is positioned at the bottom where CF3I accumulates due to its higher density, ensuring that the compressor receives refrigerant with locally higher CF3I concentration for suppressing disproportionation reaction, while the overall refrigerant mixture maintains optimized performance composition.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The invention transitions from a uniform mixture approach to a spatially differentiated approach by utilizing the vertical dimension within the refrigerant reservoir. The injection port is positioned at a specific height from the bottom, leveraging the density-based stratification of refrigerant components to deliver compositionally differentiated refrigerant to the compressor.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Productivity

If a low ratio of CF3I is used in the mixed refrigerant, then the performance of the refrigeration cycle device is maintained, but the disproportionation reaction is not suppressed

Engineering Contradiction:
Improveperformance of refrigeration cycle deviceVSAvoidstability of refrigerant composition
Core Design Contradiction:
ProductivityVSStability of the object's composition

Solution Approach 1:

The invention applies local quality by creating a spatial differentiation in CF3I concentration within the refrigerant reservoir. The injection port is positioned at the bottom where CF3I accumulates due to its higher density, ensuring that the compressor receives refrigerant with locally higher CF3I concentration for suppressing disproportionation reaction, while the overall refrigerant mixture maintains optimized performance composition.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The invention transitions from a uniform mixture approach to a spatially differentiated approach by utilizing the vertical dimension within the refrigerant reservoir. The injection port is positioned at a specific height from the bottom, leveraging the density-based stratification of refrigerant components to deliver compositionally differentiated refrigerant to the compressor.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

3Quantity of substance

If CF3I is injected from a deeper level in the refrigerant reservoir, then the ratio of CF3I injected to the compressor increases, but the complexity of the injection system increases

Engineering Contradiction:
Improveratio of CF3I injected to compressorVSAvoidcomplexity of injection system
Core Design Contradiction:
Quantity of substanceVSDevice complexity

Solution Approach 1:

The invention extracts CF3I from the bulk refrigerant mixture by utilizing its density difference and gravitational settling. The injection port positioned at the bottom of the reservoir selectively draws out the denser CF3I component, separating it from the lighter refrigerant components that remain in the upper portions of the reservoir.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The invention employs self-service by utilizing the natural density-based stratification of refrigerant components within the reservoir and the gravitational force acting on them. No additional active separation mechanisms are required; the system leverages the inherent physical properties of the refrigerant mixture to achieve compositional differentiation at the injection point.

Inventive Principle:
Principle #25Self-service

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 configuration effectively suppresses disproportionation reactions and prevents performance deterioration by ensuring a higher ratio of CF3I is injected to the compressor, optimizing the refrigeration cycle's efficiency and stability.

Implementation Method 1

CF3I has a greatest fluid density among refrigerants contained in the mixed refrigerant

Methodology Applied
Scientific EffectFluid density: Density Gradient

Implementation Method 2

the first height is lower than a height at which an end of a refrigerant pipe, other than the injection pipe, is located within the refrigerant reservoir

Methodology Applied
Scientific EffectGravitational separation: Gravitation

Data Source

PatentEP4134603B1Refrigeration cycle device
Publication Date: 2024.08.14 MITSUBISHI ELECTRIC CORP
  • EP4134603B1 patent drawingFigure 1
  • EP4134603B1 patent drawingFigure 2
  • EP4134603B1 patent drawingFigure 3

AI summary

A refrigeration cycle device includes: a refrigerant circuit (RC) which circulates a mixed refrigerant containing at least CF3I and HFO1123, the RC including a compressor (230), an expansion valve (250, 260), an indoor heat exchanger (110), an outdoor heat exchanger (210), and a refrigerant reservoir (500); an injection pipe (401) having a first end at a first height (H1) within the refrigerant reservoir (500) and a second end connected to the compressor (230); and an injection valve (400) included in the injection pipe (401). The CF3I has the greatest fluid density among refrigerants contained in the mixed refrigerant. The first height (H1) is higher than a height at which an end of a refrigerant pipe, other than the injection pipe (401), is located within the refrigerant reservoir (500).