Variable Refrigerant Flow Cooling for Motor and Magnetic Bearings
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current compressor systems experience inefficiencies due to recirculation and windage losses caused by fixed-size holes for cooling gas flow, which fail to meet the variable cooling demands of compressor parts like motors and bearings.
Innovation Solution
A flow control device with a shuttling valve assembly having different cross-sectional areas and controlled by spring and gas pressure, or solenoid valves, is placed between the volute and motor housings to dynamically adjust the flow of refrigerant, reducing recirculation and windage losses.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If fixed-size holes are used to allow compressed gas to cool compressor components, then cooling is provided to motor, shaft and bearings, but recirculation and windage losses occur due to uncontrolled gas flow
Solution Approach 1:
The patent applies the dynamics principle by replacing fixed-size cooling holes with a variable flow control device that includes a shuttling valve assembly. This assembly can dynamically adjust the flow area between the volute housing and motor housing based on operating conditions, allowing the system to optimize cooling flow and minimize recirculation and windage losses at different compressor speeds and pressure conditions.
2Adaptability or versatility
If fixed-size holes are used for cooling gas flow, then the structure is simple, but the cooling demands of compressor parts varying with speed and pressure cannot be met
Solution Approach 1:
The patent applies segmentation by dividing the flow control function into distinct components: a shuttling valve assembly with multiple valve positions, separate flow paths, and controllable opening/closing mechanisms. This segmentation allows independent control of cooling flow to different compressor components (motor, bearings, shaft) based on their specific cooling requirements at various operating conditions.
3Reliability
If compressed gas flows to cool compressor components, then cooling is achieved, but inefficiency occurs due to uncontrolled recirculation and windage
Solution Approach 1:
The patent applies feedback control through a controller that receives signals about compressor operating conditions (speed, pressure, temperature) and automatically adjusts the position of the shuttling valve assembly. This closed-loop feedback system ensures optimal cooling flow is maintained across varying operating conditions while minimizing recirculation and windage losses, thereby maintaining both cooling effectiveness and compressor efficiency.
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 solution improves compressor efficiency by providing variable coolant flow based on operational needs, reducing recirculation and windage losses, and effectively meeting the cooling demands of compressor components.
Implementation Method 1
The position of the shuttling valve may be controlled by a spring and/or gas pressure
Implementation Method 2
The position of the shuttling valve may be controlled by a spring and/or gas pressure
Implementation Method 3
The cooling may be provided, for example, by a flow of compressed gas discharged from the compressor
Data Source
AI summary
A variable orifice flow device controls the flow of refrigerant into a compressor motor housing in a compressor. The variable orifice flow device may include, for example, an electronic expansion valve, a thermal expansion valve, or a shuttling valve controlling the flow of refrigerant into a compressor motor housing. One or more flows of refrigerant may be through a fixed orifice, a valve seat of the variable orifice flow device, or leakage through a seal of the compressor motor housing, providing a baseline refrigerant flow to the inside of the compressor motor housing in addition to the flow through the variable orifice flow device.