Chiller Motor Cooling With Low-Velocity Refrigerant Spray
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Chiller systems face challenges in providing adequate motor cooling for gas compression systems, particularly with hermetic or semi-hermetic permanent magnet motors, due to inadequate cooling of motor components, risk of chemical or mechanical attack, and energy losses from high velocity refrigerant impingement.
Innovation Solution
A unique cooling system that employs a low velocity refrigerant spray on motor components, utilizing a centrifugal compressor and a motor cooling system that recirculates refrigerant without requiring pumping energy, minimizing erosion and potential chemical attacks by distributing refrigerant evenly across the motor's circumference.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If refrigerant is placed in the air gap between rotor and stator for cooling, then motor cooling is provided, but chemical or mechanical attack on magnets and components occurs
Solution Approach 1:
A non-reactive barrier layer is introduced between the refrigerant and the motor components (magnets and stator). This intermediary layer prevents direct contact between the refrigerant and sensitive components, eliminating chemical or mechanical attack while allowing thermal energy to transfer through the barrier, thus resolving the contradiction between cooling effectiveness and component protection.
Solution Approach 2:
The patent creates an inert environment by coating motor components with a protective layer that is chemically inert to the refrigerant. This inert barrier allows the refrigerant to cool the motor components without causing chemical reactions or mechanical damage, enabling effective cooling while protecting vulnerable parts from harmful effects.
2Temperature
If cooling fins create high velocity impingement of refrigerant on motor coils, then cooling effectiveness is improved, but motor component wear and pumping energy losses increase
Solution Approach 1:
The patent changes the velocity parameter of refrigerant flow by eliminating high-velocity impingement through the removal or modification of cooling fins. By reducing refrigerant velocity while maintaining adequate cooling through alternative pathways, the system achieves effective heat transfer without the energy losses and component wear associated with high-speed refrigerant jetting.
3Temperature
If cooling fins create high velocity impingement of refrigerant on motor coils, then cooling effectiveness is improved, but component wear increases
Solution Approach 1:
The patent changes the velocity parameter of refrigerant flow by eliminating high-velocity impingement through the removal or modification of cooling fins. By reducing refrigerant velocity while maintaining adequate cooling through alternative pathways, the system achieves effective heat transfer without the energy losses and component wear associated with high-speed refrigerant jetting.
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
Effectively cools motor components, reducing the risk of damage from elevated temperatures and chemical attacks, while minimizing energy losses and component wear, thus enhancing the reliability and efficiency of the gas compression system.
Implementation Method 1
a low velocity refrigerant spray on at least one of the ends of the motor
Implementation Method 2
distributing refrigerant evenly across the motor's circumference
Implementation Method 3
utilize a centrifugal compressor in a gas compression system
Data Source
AI summary
Cooling systems and methods for controlling the temperature of motors of gas compression systems of chillers are disclosed. Certain systems utilize a centrifugal, two stage compressor equipped with a motor between the stages. The cooling system provides a low velocity refrigerant spray on at least one or both ends of the motor without requiring additional pumping energy from the motor to deliver the refrigerant spray.