Cryogenic Tank Pump Drive Nesting for Volume and Thermal Isolation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional cryogenic tank assemblies face challenges in increasing fuel storage volume while mitigating the issues associated with locating a hydraulic pump drive unit within the cryogenic fuel storage and pressurizing assembly, including heat transfer and freezing of hydraulic fluid lines, which can lead to damage and reduced efficiency.
Innovation Solution
A fluid storage and pressurizing assembly with a pump drive unit partially or fully recessed within the storage receptacle, surrounded by thermal insulation, and a hydraulic weep line nested within hydraulic fluid lines to prevent freezing, allowing the pump to operate continuously at cryogenic temperatures and maintain efficient fuel delivery.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of stationary object
If the pump drive unit is located outside the storage vessel, then heat transfer to the cryogenic fluid is reduced, but the fuel storage volume is decreased due to the space occupied by the drive unit
Solution Approach 1:
The pump drive unit is nested within the storage vessel, specifically positioned within the pump receptacle that is part of the inner vessel structure. This nesting approach allows the drive unit to occupy space that would otherwise be unavailable for storage, thereby increasing fuel storage volume while maintaining thermal isolation through the vacuum insulation layer
2Volume of stationary object
If the pump drive unit is located inside the storage vessel, then fuel storage volume is increased, but the hydraulic fluid lines are subject to freezing due to cryogenic temperatures
Solution Approach 1:
The hydraulic fluid lines are segmented into distinct routing paths: the supply line extends from outside the storage vessel through the insulation layer to the pump drive unit inside, while the return line follows a similar protected path. This segmentation allows the hydraulic system to be thermally isolated from the cryogenic environment while maintaining functional connectivity
Solution Approach 2:
The pump receptacle structure and insulation layer serve as intermediary elements that thermally isolate the hydraulic fluid lines from the cryogenic fuel environment. The vacuum insulation acts as a thermal barrier, preventing heat transfer that would cause hydraulic fluid freezing while still allowing mechanical connection between the drive unit and pump
3Reliability
If thermal insulation is added to protect the pump drive unit, then freezing of hydraulic fluid lines is prevented, but heat transfer to the cryogenic fluid increases
Solution Approach 1:
The pump drive unit and hydraulic lines are nested within the inner vessel structure, which is itself nested within the vacuum insulation layer. This multi-layer nesting creates thermal barriers that protect the hydraulic system from freezing while minimizing heat transfer to the cryogenic fuel through the vacuum space
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 solution increases the fuel storage volume by incorporating the space previously occupied by the pump drive unit, reduces heat transfer to the cryogenic fluid, and prevents freezing of hydraulic fluid lines, ensuring reliable operation and efficient fuel pressurization for heavy-duty vehicles.
Implementation Method 1
The insulated space between the inner vessel and the outer vessel can be evacuated to create a vacuum insulated space
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A fluid storage and pressurizing assembly includes a storage receptacle and a pump assembly. The storage receptacle includes an inner vessel defining a cryogen space for storing a fluid at a storage pressure and a cryogenic temperature, an outer vessel surrounding the inner vessel, and an insulated space between the inner vessel and the outer vessel, and a pump assembly. The pump assembly includes a pump having an inlet disposed within the cryogen space for receiving a quantity of the fluid from the cryogen space, and an outlet for delivering the fluid therefrom, and a pump drive unit for driving the pump, the pump drive unit being at least partially disposed within a space defined by the storage receptacle.