Flexible Outer Shell for Cryogenic Vacuum Insulated Tanks
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current storage and transport of cryogenic fluids face challenges due to thermal insulation failures at low temperatures, particularly with large tanks where internal tank shrinkage leads to loss of connections and buckling instability, limiting the size and scalability of vacuum-insulated tanks.
Innovation Solution
A tank design featuring a flexible outer shell with corrugated sections that accommodate thermal contraction, combined with a vacuum-insulated system using modular block elements and a lattice pressure vessel for the inner tank, ensuring efficient thermal insulation and maintaining airtightness across varying temperatures and sizes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If a rigid outer shell is used in traditional double shell vacuum tanks, then structural stability is maintained, but the shell buckles under external atmospheric pressure when the inner tank shrinks at cryogenic temperatures
Solution Approach 1:
The outer shell is designed as a flexible membrane that can deform and accommodate the thermal contraction of the inner tank at cryogenic temperatures. This flexible membrane structure prevents buckling instability by allowing controlled deformation rather than rigid resistance to the pressure differential between atmospheric pressure outside and vacuum inside.
2Stability of the object's composition
If the inner tank is made rigid to maintain shape, then structural integrity is ensured, but thermal shrinkage at cryogenic temperatures causes loss of connections and spacing issues
Solution Approach 1:
The system transitions from a static rigid structure to a dynamic system where the flexible outer membrane adapts to the changing dimensions of the inner tank during thermal contraction. The membrane's ability to deform dynamically ensures continuous connection and spacing maintenance throughout the temperature range.
3Loss of energy
If vacuum insulation is applied to large tanks, then thermal insulation performance is improved, but the outer shell becomes increasingly unstable and prone to buckling
Solution Approach 1:
The flexible outer membrane replaces the traditional rigid shell, allowing the vacuum insulation system to scale to large tank sizes without buckling instability. The membrane's flexibility accommodates the pressure differential and thermal contraction forces that would cause rigid shells to buckle, enabling effective vacuum insulation in large-scale applications.
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 provides effective thermal insulation for cryogenic fluids, preventing excessive pressure buildup and allowing for tanks of any size and shape, while minimizing stress concentrations and maintaining airtightness, thus overcoming the limitations of traditional vacuum-insulated tanks.
Implementation Method 1
the volume between the inner tank and the outer shell is at vacuum
Implementation Method 2
thermal insulation is arranged outside the inner tank
Implementation Method 3
parts of the outer shell covering the gaps between the block elements have inward or outward oriented curved shape if seen in cross section along the respective gaps and are flexible by contracting or stretching the curved shape
Implementation Method 4
The absence of matter at vacuum results in that thermal conductivity and thermal convection in principle are eliminated as heat transfer mechanisms
Data Source
AI summary
The invention provides a tank feasible for cryogenic service and a method of building the tank. The tank comprises: an inner tank, thermal insulation, and an outer shell that is airtight, wherein the thermal insulation is arranged outside the inner tank and the outer shell is arranged outside the thermal insulation, further comprising a coupling through the outer shell, wherein a vacuum pump outside the tank can be coupled for suction of air and gas from the volume between the inner pressure tank and the outer shell, and further comprising an opening from outside the tank to inside the inner tank for loading and unloading of fluid, wherein the inner tank in operation contains fluid and the volume between the inner tank and the outer shell is at vacuum. The tank is distinguished in that: the thermal insulation comprises several block elements arranged side by side on the inner tank, with a gap in between the block elements, wherein the outer shell comprises several parts that have been joined together to cover the whole outer surface of the insulation, wherein parts of the outer shell covering an insulation block element have shape matching the insulation block element shape and parts of the outer shell covering the gaps between the block elements have inward or outward oriented curved shape if seen in cross section along the respective gaps and are flexible by contracting or stretching the curved shape.