Refrigeration cycle device
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Solution Overview
Problem
Refrigerating cycle apparatuses using prior-art ejectors experience performance degradation due to pressure loss when the ejector is bypassed, leading to reduced cooling efficiency.
Innovation Solution
Incorporating a check valve or a movable nozzle section with an electromagnetic coil to bypass the ejector during low ejector performance conditions, reducing pressure loss by minimizing internal flow resistance and maintaining efficient refrigerant circulation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the ejector is bypassed during normal operation, then the refrigerating cycle apparatus can operate when ejector performance is lowered, but pressure loss occurs while passing through the suction section of the ejector causing performance degradation
Solution Approach 1:
The suction section of the ejector is extracted and replaced with a check valve in the bypass line. This removes the harmful pressure loss component from the bypass path while maintaining the ability to bypass the ejector when needed, thus resolving the contradiction between operational reliability and pressure loss.
Solution Approach 2:
A check valve is introduced as an intermediary component in the bypass line. This check valve allows refrigerant to pass through the bypass with minimal resistance when the ejector is not functioning, while preventing backflow. It mediates between the need to bypass the ejector and the need to minimize pressure loss.
2Loss of energy
If a check valve is installed in the bypass line, then pressure loss is reduced, but device complexity increases
Solution Approach 1:
The check valve is designed to operate automatically based on pressure differential, without requiring external control systems. It self-regulates the bypass flow based on ejector performance, reducing device complexity while maintaining low pressure loss benefits.
3Loss of energy
If the check valve is positioned near the compressor suction, then pressure drop at compressor suction is prevented, but the risk of liquid refrigerant damage to compressor increases
Solution Approach 1:
The check valve is positioned upstream of the compressor suction to preliminarily establish proper pressure conditions before refrigerant enters the compressor. This preliminary pressure stabilization prevents both excessive pressure drop and liquid slugging by ensuring proper vaporization occurs before compression.
Solution Approach 2:
The bypass line with check valve is designed with specific local characteristics (diameter, length, positioning) optimized for pressure recovery without creating liquid accumulation zones. The local geometry is tailored to prevent liquid damage while maintaining pressure benefits.
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
The solution significantly reduces pressure loss and enhances cooling performance by preventing pressure drop at the compressor suction section, thereby improving the Coefficient Of Performance (COP) and maintaining efficient refrigeration cycles.
Implementation Method 1
Incorporating a check valve or a movable nozzle section with an electromagnetic coil to bypass the ejector during low ejector performance conditions, reducing pressure loss by minimizing internal flow resistance
Implementation Method 2
movable nozzle section with an electromagnetic coil
Data Source
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AI summary
To obtain a refrigerating cycle apparatus that reduces a pressure loss at the time of a normal operation in which an ejector is bypassed to improve refrigeration cycle performance. A second throttle apparatus 12 is installed on piping path between the outlet of a condenser 2, which is a radiator, and the outlet of a first throttle device 11. A check valve 13 is installed on piping path between a gas refrigerant suction section 41 b of the ejector 3 and the outlet of the ejector 3.