Working fluid composition and refrigerator
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing refrigerating machines face challenges in achieving desired characteristics through appropriate combinations of refrigerants and refrigerating machine oils, leading to suboptimal performance and stability.
Innovation Solution
A novel working fluid composition comprising a refrigerating machine oil with specific base oils and additives, including polyol ester and polyvinyl ether, along with a refrigerant mixture of trans-1,2-difluoroethylene (HFO-1132) and 2,3,3,3-tetrafluoropropene (HFO-1234yf), optimized for refrigerant dissolution viscosity and stability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional refrigerating machine oils are used with HFO-1234yf refrigerant, then the system operates with standard lubrication properties, but the refrigerant dissolution viscosity is insufficient and stability is poor
Solution Approach 1:
The patent changes the chemical composition parameters of the refrigerating machine oil by specifying particular base oils (polyol ester with specific hydroxyl values, polyvinyl ether with specific viscosity characteristics) and additive combinations (carbodiimide-based acid scavenger at 0.01-5 wt%, phenol-based antioxidant at 0.01-5 wt%). These parameter changes result in improved refrigerant dissolution viscosity and enhanced stability when used with HFO-1234yf refrigerant.
Solution Approach 2:
The patent creates a composite refrigerating machine oil by combining multiple components: base oil (polyol ester or polyvinyl ether), carbodiimide-based acid scavenger, and phenol-based antioxidant. This composite formulation achieves synergistic effects that improve both refrigerant dissolution viscosity and system stability, resolving the contradiction between these two properties.
2Object-affected harmful factors
If the refrigerant composition is changed to improve environmental performance, then GWP is reduced, but the compatibility with existing refrigerating machine oils deteriorates
Solution Approach 1:
The patent uses HFO-1234yf refrigerant which has significantly lower GWP (approximately 150) compared to conventional HFC refrigerants like R404A (GWP approximately 150) or R134a (GWP approximately 143). Simultaneously, the patent modifies the refrigerating machine oil parameters to ensure compatibility, achieving both environmental performance and reliable operation.
Solution Approach 2:
The patent introduces specific additives (carbodiimide-based acid scavenger and phenol-based antioxidant) as intermediaries that mediate between the HFO-1234yf refrigerant and the base oil. These additives improve compatibility by preventing degradation reactions and maintaining stable lubrication properties, thus resolving the compatibility issue while maintaining low GWP.
Data Source
AI summary
A working fluid composition containing a refrigerating machine oil; and a refrigerant containing trans-1,2-difluoroethylene (HFO-1132 (E)) and 2,3,3,3-tetrafluoropropene (HFO-1234yf), wherein the working fluid composition has a refrigerant fraction at 80° C. and 2.5 MPa of 80% by mass or less, wherein the refrigerating machine oil contains: at least one base oil selected from the group consisting of a polyol ester and a polyvinyl ether; a carbodiimide-based acid scavenger; and a phenol-based antioxidant.