Membrane Evaporative Cooling for High-Capacity Refrigerant Absorption
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The capacity of desiccants to store refrigerant and transfer heat in evaporative cooling systems is limited, which restricts the effectiveness and utility of cooling operations, especially in wellbore environments.
Innovation Solution
An evaporative cooling apparatus featuring a heat transfer module with a liquid refrigerant and a heat absorbing module using a selectively permeable membrane to condense vapor back into liquid, with glycerol as the drawing fluid to enhance refrigerant storage and heat transfer efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If a desiccant is used to absorb refrigerant vapor and transfer heat, then cooling function is provided, but the desiccant capacity to store refrigerant is limited and heat load transfer efficiency is insufficient
Solution Approach 1:
The patent employs a selectively permeable membrane with controlled pore structure that allows refrigerant vapor to pass through while blocking the drawing fluid. The membrane's pore size and selectivity enable efficient vapor condensation and drawing fluid penetration resistance, directly addressing the limited storage capacity and heat transfer efficiency of conventional desiccants.
Solution Approach 2:
The patent changes the physical state parameters by using phase transition of the refrigerant (evaporation and condensation) and controlling the membrane permeability parameters. The selective permeability and pore size control allow optimization of both refrigerant vapor absorption and heat transfer characteristics, overcoming the fixed limitations of traditional desiccant materials.
2Quantity of substance
If the desiccant volume is increased to improve refrigerant storage, then storage capacity increases, but the device complexity and space requirements increase
Solution Approach 1:
The selectively permeable membrane provides high surface area and controlled pore structure within a compact form factor. This allows significant refrigerant vapor condensation and storage capacity without requiring large volumes of desiccant material, as the membrane's selective permeability concentrates the refrigerant absorption function in a thin, space-efficient structure.
Solution Approach 2:
The vapor chamber is positioned within the drawing fluid container, creating a nested configuration where the membrane separates the two functional zones. This nested arrangement maximizes the use of available space, allowing the refrigerant storage and heat transfer functions to be integrated in a compact, multi-functional structure.
3Ease of manufacture
If conventional desiccant materials are used, then the system structure is simple, but the heat transfer efficiency and refrigerant absorption capability are insufficient
Solution Approach 1:
The selectively permeable membrane acts as an intermediary between the refrigerant vapor and the drawing fluid. It mediates the mass and heat transfer processes by allowing vapor passage while blocking liquid drawing fluid, enabling efficient refrigerant absorption and heat transfer without requiring complex multi-component systems.
Solution Approach 2:
The patent utilizes phase transition of the refrigerant (liquid to vapor during evaporation, vapor to liquid during condensation) as the core cooling mechanism. The membrane facilitates this phase change process by providing a selective interface that enhances condensation efficiency while maintaining system structural simplicity.
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 system effectively increases refrigerant storage capacity and reduces heat load transfer, improving cooling operations in wellbore environments and other applications by utilizing a ceramic membrane with pore sizes between 1 nm and 200 nm to selectively allow water vapor passage while preventing glycerol diffusion, leveraging osmotic pressures to efficiently condense and absorb heat.
Implementation Method 1
evaporating a refrigerant stored in the downhole tool from a liquid phase to a gaseous phase
Implementation Method 2
As liquid evaporates, that component is cooled while, on the other side, the evaporated refrigerant carrying the heat
Implementation Method 3
The vapor chamber has a selectively permeable membrane configured to: (i) condense refrigerant vapor to a liquid
Implementation Method 4
a drawing liquid in the second container and selected to absorb the liquid refrigerant
Implementation Method 5
leveraging osmotic pressures to efficiently condense and absorb heat
Implementation Method 6
The vapor chamber has a selectively permeable membrane configured to: (ii) block flow of the drawing fluid into the vapor chamber
Data Source
AI summary
An evaporative cooling apparatus may include a heat transfer module having a vapor passage in fluid communication with a liquid refrigerant in a first container and a heat absorbing module having a drawing liquid selected to absorb the liquid refrigerant in the second container. The heat absorbing module also has a vapor chamber in the drawing fluid that receives vapor generated during evaporation of the liquid refrigerant. The vapor chamber has a selectively permeable membrane that: (i) transports the vapor to the drawing liquid, and (ii) blocks flow of the drawing fluid into the vapor chamber. The refrigerant may be liquid water, the vapor chamber may include a selectively permeable membrane having a pore size between 1 nm and 200 nm, and the drawing fluid may be glycerol.