Deep freezer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Deep freezers face challenges in achieving a desired very low temperature environment while maintaining compressor reliability and reducing noise, as existing refrigerant mixtures often result in high discharge pressure and increased dryness, leading to reduced cooling power and compressor reliability.
Innovation Solution
The implementation of a deep freezer design featuring multiple heat exchangers in the suction pipe to optimize the refrigerant mixture's heat exchange, specifically using a mixture of N-butane and ethylene with a weight ratio of 80:20 to 85:15, and a household compressor operating within a set pressure range to reduce condensing pressure and noise.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If a non-azeotropic refrigerant mixture is used to realize deep temperature, then the desired very low temperature environment is achieved, but the discharge pressure and condensing pressure of the compressor increase
Solution Approach 1:
The patent optimizes the composition ratio parameters of the non-azeotropic refrigerant mixture (specifically R404A and R507EA components) to achieve a balance between low temperature performance and acceptable discharge pressure levels, allowing the system to operate within compressor capabilities while maintaining deep freezing temperatures
Solution Approach 2:
The patent uses a composite refrigerant mixture combining multiple refrigerants (R404A, R507EA, and their components) with specific composition ratios to achieve both deep temperature capability and manageable pressure characteristics that a single refrigerant cannot provide
2Temperature
If a commercial compressor with large operating pressure range is used to handle high discharge pressure, then deep temperature is achieved, but operation noise increases and reliability deteriorates
Solution Approach 1:
By optimizing the refrigerant mixture composition ratios, the patent reduces the discharge pressure to a level that allows the use of household compressors with smaller pressure ranges, thereby improving reliability and reducing noise while still achieving deep freezing temperatures through the thermodynamic properties of the optimized mixture
3Stress or pressure
If the ratio of refrigerant with high boiling point is increased, then compressor discharge pressure decreases, but deep temperature realization becomes difficult
Solution Approach 1:
The patent precisely optimizes the composition ratios of high boiling point and low boiling point refrigerants in the mixture to achieve the optimal balance point where both acceptable discharge pressure and deep temperature capability are simultaneously realized
4Temperature
If the ratio of refrigerant with low boiling point is increased, then deep temperature is achieved, but discharge pressure increases and compressor reliability deteriorates
Solution Approach 1:
The patent determines the optimal composition ratio range for low boiling point refrigerant components in the non-azeotropic mixture, achieving deep temperature performance while keeping discharge pressure within acceptable limits for reliable compressor operation
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 decreases condensing pressure, prevents dryness increase, and enhances compressor reliability by optimizing the refrigerant mixture, allowing for a desired very low temperature environment with improved cooling power and reduced noise.
Implementation Method 1
a plurality of heat exchangers installed in a suction pipe to perform heat exchange of a refrigerant mixture sucked into a compressor
Implementation Method 2
the temperature of which is not changed in a quasi-equilibrium state when liquefaction or vaporization occurs between liquid and gas at a predetermined pressure
Implementation Method 3
the discharge pressure of a compressor increases
Data Source
AI summary
An embodiment of the present invention relates to a deep freezer. A deep freezer according to an embodiment of the present invention comprises a plurality of heat exchangers installed to an inlet pipe and performing a heat exchange of a mixed refrigerant suctioned into a compressor. The mixed refrigerant comprises: a high temperature refrigerant which is one selected from among butane (N-butane), 1-butene, and isobutane; and a low temperature refrigerant consisting of ethylene.