Ejector refrigeration cycle device
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional refrigeration cycle devices face challenges in achieving both high air heating capacity and cycle efficiency during air-heating operations, particularly at ultralow temperatures, due to increased compressor driving power when reducing refrigerant evaporation pressure.
Innovation Solution
An ejector refrigeration cycle device is introduced, featuring a compressor, radiator, first decompressor, first exterior heat exchanger, ejector with nozzle, branch, and second exterior heat exchanger, which allows for pressurization of refrigerant through the ejector's nozzle and suction ports, enabling lower evaporation pressure and reduced compressor power consumption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If refrigerant evaporation pressure is reduced to secure air heating capacity, then air heating capacity is improved, but compressor driving power is increased and cycle efficiency deteriorates
Solution Approach 1:
The ejector is introduced as an intermediary device between the first exterior heat exchanger and the compressor. It uses a high-pressure refrigerant jet from the nozzle to create a suction effect that draws refrigerant from the first exterior heat exchanger, and a pressurizing effect in the diffuser that raises the suction pressure to the compressor. This intermediary mechanism allows the system to maintain both adequate evaporation pressure for heating capacity and high suction pressure for compressor efficiency.
Solution Approach 2:
The ejector changes the pressure parameters of the refrigerant through its nozzle and diffuser structure. The nozzle converts high-pressure refrigerant into a high-velocity jet, while the diffuser converts this kinetic energy back into pressure energy. This parameter transformation enables the system to operate with lower evaporation pressure in the first exterior heat exchanger while maintaining high suction pressure at the compressor, resolving the contradiction between heating capacity and energy efficiency.
2Temperature
If refrigerant evaporation pressure is reduced to secure air heating capacity, then air heating capacity is improved, but cycle efficiency deteriorates
Solution Approach 1:
The ejector serves as a mediator that recovers and utilizes the energy from the high-pressure refrigerant jet. Instead of this energy being wasted, it is used to create the suction effect and pressurizing effect, thereby reducing the overall energy loss in the cycle and improving cycle efficiency while maintaining low evaporation temperature for adequate heating capacity.
Solution Approach 2:
The ejector converts what would otherwise be wasted high-pressure refrigerant energy into useful suction and pressurizing effects. The high-pressure refrigerant expanding through the nozzle creates a low-pressure zone that draws in more refrigerant (suction effect), and the subsequent diffuser converts the kinetic energy back to pressure (pressurizing effect), turning a potentially harmful pressure drop into a beneficial energy recovery mechanism.
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 enhances air heating capacity and cycle efficiency by decreasing refrigerant evaporation temperature in the first exterior heat exchanger and increasing compressor suction pressure, thereby improving both air heating performance and energy efficiency during air-heating operations.
Implementation Method 1
a nozzle portion (41) that decompresses the refrigerant flowing out of the radiator
Implementation Method 2
a nozzle portion (41) that decompresses the refrigerant flowing out of the radiator
Implementation Method 3
a refrigerant suction port (18b) that draws the refrigerant heat-exchanged in the first exterior heat exchanger (22) by a suction effect of the refrigerant injected from the nozzle portion
Implementation Method 4
a pressurizing portion (42b) that mixes the refrigerant injected from the nozzle portion (41) and the refrigerant drawn from the refrigerant suction port (18b) to pressurize the mixed refrigerant
Data Source
AI summary
An ejector refrigeration cycle device includes: a decompressor that decompresses a refrigerant heat-exchanged in a radiator; a first exterior heat exchanger that exchanges heat between the refrigerant decompressed by the decompressor and outside air; an ejector that decompresses the refrigerant flowing out of the radiator in a nozzle portion and draws another refrigerant heat-exchanged in the first exterior heat exchanger; a branch portion in which the refrigerant heat-exchanged in the radiator branches to a side of the decompressor and a side of the nozzle portion; a second exterior heat exchanger that exchanges heat between the refrigerant pressurized in the ejector and the outside air; a bypass portion that causes the refrigerant heat-exchanged in the radiator to flow to the first exterior heat exchanger while bypassing the decompressor and the nozzle portion; and an opening/closing portion that opens or closes the bypass portion.