Short answer

When designing composite cryogenic tanks, carefully consider the trade-offs between structural requirements and the increased risk of damage associated with thicker CFRP laminates under cryogenic conditions. Explore alternative lay-ups or material systems if significant thickness is unavoidable.

Field: Final Production
Source: Arrow@dit (Dublin Institute of Technology) (2015)
Method: Experimental investigation combined with numerical simulation.
Evidence: Strong effect

Increased laminate thickness in carbon fibre reinforced polymers (CFRP) directly correlates with a higher propensity for microcracking and delamination when subjected to cryogenic thermal cycling. This final production research insight is drawn from a 2015 study published in Arrow@dit (Dublin Institute of Technology). Using Experimental investigation combined with numerical simulation., researchers explored how this design variable affects real-world outcomes. The key design takeaway: When designing composite cryogenic tanks, carefully consider the trade-offs between structural requirements and the increased risk of damage associated with thicker CFRP laminates under cryogenic conditions. Explore alternative lay-ups or material systems if significant thickness is unavoidable.

Study

Final ProductionHigh ImpactStrong effect

Thicker CFRP laminates exhibit higher microcrack density and delamination under cryogenic cycling

Increased laminate thickness in carbon fibre reinforced polymers (CFRP) directly correlates with a higher propensity for microcracking and delamination when subjected to cryogenic thermal cycling.

Arrow@dit (Dublin Institute of Technology) · 2015

Key Findings

01Thicker CFRP laminates exhibit significantly greater microcrack density and delamination compared to thinner laminates under cryogenic cycling.
02Initial interlaminar defects can influence subsequent delamination growth.
03Delamination length is related to material permeability.
04Microcracking induced by thermal residual stresses was observed in thicker laminates post-processing.

Application

Design takeaway

How to apply

When selecting materials for cryogenic applications, conduct thorough analysis of the impact of laminate thickness on damage accumulation under expected operational temperatures and cycling. Consider non-destructive testing methods to assess internal damage.

Project actions

01When choosing materials for a design project, consider how thickness affects durability under extreme conditions.
02Use microscopy or CT scanning if possible to examine internal material damage.

Method & Evidence

AimTo investigate the relationship between laminate thickness and damage accumulation (microcracking and delamination) in CFRP under cryogenic conditions.

MethodExperimental investigation combined with numerical simulation.

ProcedureCFRP laminates of varying thicknesses were subjected to cryogenic thermal cycling. Damage formation was assessed using optical microscopy and 3D X-ray computed tomography (CT). A novel XFEM-based methodology was developed to simulate thermal fatigue delamination and predict laminate permeability based on crack opening displacement.

ContextDevelopment of linerless composite cryogenic tanks for reusable launch vehicles.

Variables

IVLaminate thickness

DVMicrocrack density, delamination extent

CVCryogenic cycling conditions, material type (CF/PEEK), lay-up

Strengths & Limitations

Strengths

+Combines experimental observation with advanced numerical modelling.
+Utilizes sophisticated imaging techniques (3D X-ray CT) for detailed damage analysis.

Limitations

The cost and accessibility of advanced imaging techniques like 3D X-ray CT can be a barrier for smaller design projects.

Reliability & validity

The use of multiple validation methods (experimental and numerical) and detailed imaging techniques enhances the reliability and validity of the findings regarding damage accumulation.

Think critically

How might design choices, beyond simple thickness, influence the mitigation of microcracking and delamination in composite cryogenic tanks?

Design Principles

"For cryogenic composite applications, minimize laminate thickness where possible to reduce the likelihood of microcracking and delamination, and account for the impact of thermal residual stresses during processing."

This finding is crucial for designers and engineers developing cryogenic fuel tanks for reusable launch vehicles. Understanding how laminate thickness influences damage accumulation directly impacts the structural integrity, safety, and long-term performance of these critical components.

What This Means for Your Design

If you make a composite material thicker, it's more likely to crack and split apart when it gets very cold, which could make it leak.

How to use in your project

1.Reference this study when discussing material selection for components subjected to thermal stress or extreme temperatures, particularly if considering composite materials and varying thicknesses.

Add to My Project

Quick Cite

Paragraph starter

Research indicates that for carbon fibre reinforced polymer (CFRP) components intended for cryogenic applications, such as fuel tanks, increased laminate thickness significantly exacerbates damage accumulation. Specifically, thicker laminates demonstrate a higher density of microcracks and a greater propensity for delamination when subjected to cryogenic thermal cycling, potentially compromising structural integrity and permeability characteristics.

Source

Arrow@dit (Dublin Institute of Technology)

Damage and permeability in linerless composite cryogenic tanks

journal · 2015

View source

Questions About This Research

What does the research say about thicker cfrp laminates exhibit higher microcrack density and delamination under cryogenic cycling?: When designing composite cryogenic tanks, carefully consider the trade-offs between structural requirements and the increased risk of damage associated with thicker CFRP laminates under cryogenic conditions. Explore alternative lay-ups or material systems if significant thickness is unavoidable. Evidence: Arrow@dit (Dublin Institute of Technology) (2015).
Why does "Thicker CFRP laminates exhibit higher microcrack density and delamination under cryogenic cycling" matter for design?: This finding is crucial for designers and engineers developing cryogenic fuel tanks for reusable launch vehicles. Understanding how laminate thickness influences damage accumulation directly impacts the structural integrity, safety, and long-term performance of these critical components.
How can designers apply this research?: When designing composite cryogenic tanks, carefully consider the trade-offs between structural requirements and the increased risk of damage associated with thicker CFRP laminates under cryogenic conditions. Explore alternative lay-ups or material systems if significant thickness is unavoidable.
What were the main findings?: Thicker CFRP laminates exhibit significantly greater microcrack density and delamination compared to thinner laminates under cryogenic cycling.. Initial interlaminar defects can influence subsequent delamination growth.. Delamination length is related to material permeability.. Microcracking induced by thermal residual stresses was observed in thicker laminates post-processing.
What research method was used?: Experimental investigation combined with numerical simulation..
How strong is the evidence?: Evidence strength is rated Strong effect, based on a 2015 journal from Arrow@dit (Dublin Institute of Technology).
What should I do differently in my next project?: When selecting materials for cryogenic applications, conduct thorough analysis of the impact of laminate thickness on damage accumulation under expected operational temperatures and cycling. Consider non-destructive testing methods to assess internal damage.
What are the limitations?: The study focused on specific CFRP materials (CF/PEEK) and lay-ups; results may vary with different material systems. The long-term effects of damage on tank performance were not fully explored.