Dual-Evaporator Vehicle AC Refrigerant Flow Ratio Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing refrigerant cycle for air conditioners in vehicles has limitations in enhancing cooling performance and efficiency due to a single evaporator unit, which restricts radiating performance and cooling efficiency (COP), and requires optimization of refrigerant flow ratio and pressure drop management.
Innovation Solution
The implementation of a refrigerant cycle with a first and second evaporating unit disposed upstream and downstream in the air flow direction, utilizing a dual supply passage expansion valve to control refrigerant flow ratio and reduce pressure drop, allowing for increased refrigerant flow and improved evaporation conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a single evaporator unit is used, then the device complexity is reduced, but the cooling performance and radiating performance are limited
Solution Approach 1:
The evaporator is divided into a first evaporating unit and a second evaporating unit, allowing independent refrigerant flow control to each unit. This segmentation enables optimized heat exchange in different regions, improving overall cooling performance while maintaining manageable system complexity through modular design.
2Ease of operation
If refrigerant flow ratio is not optimized, then the system is simpler to operate, but the cooling efficiency (COP) is reduced
Solution Approach 1:
The system employs dynamic refrigerant flow control through expansion valves that adjust the refrigerant distribution ratio between the first and second evaporating units based on real-time cooling demands. This dynamic adjustment optimizes cooling efficiency (COP) by matching refrigerant supply to actual heat exchange requirements in each evaporating unit.
3Device complexity
If pressure drop is not reduced, then the refrigerant passage can be simpler, but the refrigerant flow and evaporation conditionality are reduced
Solution Approach 1:
The refrigerant passage is designed with locally optimized characteristics, including varying cross-sectional areas and strategic placement of expansion valves at different locations. The first and second evaporating units have tailored passage configurations that minimize pressure drops in high-flow regions while maintaining adequate pressure differentials for effective refrigerant circulation and evaporation.
4Device complexity
If the refrigerant passage length is not shortened, then the evaporator structure can be simpler, but the refrigerant flow velocity and evaporation efficiency are reduced
Solution Approach 1:
The evaporator design utilizes three-dimensional spatial arrangement of the first and second evaporating units, optimizing the refrigerant passage routing in multiple dimensions. This approach shortens the effective refrigerant flow path length while maintaining adequate heat exchange surface area, thereby improving refrigerant flow velocity and evaporation efficiency without excessively complicating the overall evaporator structure.
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 cooling performance and efficiency by optimizing refrigerant flow ratio and reducing pressure drop, achieving optimal radiating performance and COP, while simultaneously supplying refrigerant to both evaporating units.
Implementation Method 1
a compressor 1 compressing and delivering a refrigerant
Implementation Method 2
a condenser 2 condensing the high-temperature and high-pressure gas refrigerant into a high-temperature and high-pressure liquid by heat-exchanging the gas refrigerant with outside air
Implementation Method 3
an expansion valve 3 throttling the refrigerant condensed and liquefied in the condenser 2
Implementation Method 4
an evaporator 4 evaporating the low-pressure liquid refrigerant throttled in the expander 3 by heat-exchanging it with air blown to the inside of a car to cool air discharged to the inside of a car by an endothermic action due to evaporation latent heat
Data Source
AI summary
Provided is a refrigerant cycle of an air conditioner for vehicles, and more particularly, a refrigerant cycle of an air conditioner for vehicles having a first evaporating unit and a second evaporating unit disposed upstream and downstream in a direction in which air blown from a single blower flows to control an amount of the refrigerant supplied to each evaporating unit, thereby making it possible to obtain optimal radiating performance (cooling performance) and cooling efficiency (COP) through the design of the optimal refrigerant flow ratio depending on the cooling load.