Blood Processing Unit Counter-Current Heat Exchanger
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current blood perfusion systems for cardiopulmonary bypass surgery lack efficient temperature regulation, as existing oxygenators do not effectively utilize counter-current flow to enhance heat transfer between blood and heat exchanger fluid, leading to suboptimal temperature control during surgical procedures.
Innovation Solution
A blood processing apparatus with a housing containing a heat exchanger core and a cylindrical shell, featuring a blood flow distributor and a fluid flow distributor, which facilitate counter-current flow between blood and heat exchanger fluid through radially distributed apertures, optimizing heat exchange by directing blood and heat exchanger fluid in opposing directions within the heat exchanger chamber.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If conventional oxygenators are used without counter-current flow configuration, then the device complexity is reduced, but the heat transfer efficiency and temperature regulation capability deteriorate
Solution Approach 1:
The heat exchanger is segmented into multiple hollow fiber bundles arranged in counter-current flow paths, with separate inlet and outlet chambers for blood and heat exchanger fluid. This segmentation enables efficient heat transfer while maintaining manageable structural complexity through modular organization of the fibers and chambers.
Solution Approach 2:
The invention utilizes hydraulic flow through hollow fibers to achieve counter-current heat exchange. Blood flows through the hollow fibers while heat exchanger fluid flows in the opposite direction through the inter-fiber space, maximizing thermal efficiency through fluid dynamic design without requiring mechanical moving parts.
2Productivity
If counter-current flow configuration is implemented, then heat transfer efficiency is improved, but the device complexity increases
Solution Approach 1:
The hollow fiber bundle serves multiple functions simultaneously: it acts as the blood flow pathway, the heat transfer interface, and the structural support element. This multi-functionality achieves high heat transfer efficiency while avoiding the need for separate components, thereby limiting the increase in device complexity.
Solution Approach 2:
The hollow fibers are nested within a cylindrical housing that contains the heat exchanger chambers and flow distributors. This nested arrangement compactly integrates the counter-current flow paths and heat transfer surfaces, achieving high productivity within a constrained structural footprint.
3Measurement precision
If conventional single-direction flow is used, then the device complexity is minimized, but the temperature control precision deteriorates
Solution Approach 1:
The heat exchanger is designed with locally optimized flow distribution, where blood and heat exchanger fluid are introduced at opposite ends and flow through dedicated inlet and outlet chambers. This local quality enhancement at the flow entry/exit points ensures uniform temperature control precision throughout the blood path without requiring complex system-wide control mechanisms.
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 counter-current flow configuration significantly improves heat transfer, enabling more responsive temperature regulation of blood, thereby enhancing the efficiency and precision of temperature management during cardiopulmonary bypass procedures.
Implementation Method 1
a plurality of heat exchanger hollow fibers disposed in the heat exchanger chamber, the heat exchanger hollow fibers configured to direct heat exchanger fluid from the heat exchanger fluid inlet at the second end through the heat exchanger hollow fibers to a fluid flow distributor near the first end
Implementation Method 2
The counter-current flow configuration significantly improves heat transfer, enabling more responsive temperature regulation of blood, thereby enhancing the efficiency and precision of temperature management during cardiopulmonary bypass procedures.
Data Source
AI summary
Described is a blood processing apparatus with a blood flow path and a heat exchanger fluid flow path overlapping the a heat exchanger chamber, in which the blood flows generally from a first end to a second end of the blood processing apparatus, and the heat exchanger fluid flows generally from the second end to the first end. Such “counter” or “countercurrent” flow improves heat transfer between the blood and the heat exchanger fluid. The blood processing apparatus includes a housing, a blood inlet, a heat exchanger fluid inlet and a heat exchanger fluid outlet, a heat exchanger core, a cylindrical shell having an annular shell aperture, a blood flow distributor, and a central chamber in fluid communication to a fluid flow distributor.