STRUCTUAL ANALYSIS (FEA)

Helping operators and equipment manufacturers

Structural analysis projects typically include the identification and risk assessment of failure modes. Common failure modes are mechanical overloading, plastic collapse, localised yielding or wear. We are familiar with assessing structures to various design codes such as   ASME VIII Div. 2, BS EN ISO 3449:2008., DEF STAN 08-123, BR 3021, MIL-STD-810, RTCA DO-160 and DN-RP-F112.

However, we have also investigated other potential causes of failure such as hydrogen embrittlement and ageing, including stress corrosion cracking of stainless steel subsea equipment to DN-RP-F112.

We can predict progressive failure using advanced fracture mechanics capabilities, including application of the Paris Law for aluminium structures.

Mixing simulation

Often structural stress is caused by temperature gradients. Both steady-state and transient thermal analysis have been undertaken using Ansys and other FEA codes.

We have simulated thermal cracking of ceramic refractory tiles due to quenching processes, in addition to thermo-mechanical simulations for a diverse range of products including engine ice protection systems, ceramic catalysts, oil well plug systems and roof tiles. Results have been validated through physical test data and thermal shock tests.

Our structural analysis and fluid dynamics capabilities can be combined to study fluid-structure interaction (FSI) behaviour, including both thermal and pressure loading.

Accurately modelling valve closure dynamics

We regularly undertake design assessment for code compliance. We are very familiar with PD5500, Eurocode and ASME VIII & ASME V Design by Analysis for pressure vessel and related equipment, including stress linearisation. We also undertake the bespoke assessment of designs not in-line with conventional codes and standards.

We also run a popular software-neutral Design By Analysis training course to help engineers meet the requirements of ASME VIII Div. 2 using Finite Element Analysis (FEA).

Improving pedestrian comfort and safety

We support both implicit and explicit dynamic analysis with Ansys Mechanical and Ansys LS-DYNA, in addition to kinematic (rigid body) simulations to extract dynamic loads from reciprocating machinery. Natural frequency (modal), harmonic, response spectrum and random vibration applications are common to understand how a system performs relative to its critical frequencies.

Projects range from automotive after treatment systems, fuel oil coolers, nuclear gloveboxes to gas holders. Sources of dynamic loads vary widely, from gas pulsations within internal baffles and rotating equipment to road vibrations and seismic events.

Through our long-term relationship with the off-road vehicle industry, we are highly experienced in transient dynamic analysis such as the assessment of falling object protective structures (FOPS) to BS EN ISO 3449:2008. Impact or blast simulations have included mobile phone drop tests to regulatory requirements and explosion-resistant safety enclosures for ATEX certification, together with shock testing for marine applications to recognised standards such as BV 0430.

Fluid-Structure Interaction (FSI) analysis

A major consideration for many load-bearing structures, we predict buckling-capacity safety-factors using both linear and non-linear approaches. Some examples of recent projects include offshore fabricated towers, railway masts, bridges and outdoor storage tanks subject to variable wind loading.

Fluid-Structure Interaction (FSI) analysis

Fatigue life prediction of structures and systems has been one of our most common applications over three decades, correlating results with physical test data where it is available. Whether the excitations are static or dynamic, regular or completely random, we ensure designs meet their requirements for safe-life or damage-tolerant design.

We have experience in fatigue life predictions within many industries, from mixing vessels and ship-based rotating equipment to speciality bridges subject to multiple crossings, applying relevant codes such as Eurocode, PD5500 and DNV CN30-7.

Fluid-Structure Interaction (FSI) analysis

In addition to ‘linear’ metallic materials, we are also very familiar with hyperelastic and creep modelling of polymers and rubbers for seals, housings and other products.

We can translate complex non-linear behaviour into efficient material models suitable for FEA. This includes the project management of material physical tests and development & validation of constitutive models to implement within our clients’ analysis software.

We have significant experience handling large deformation problems involving extensive contact and rigid body motion, covering nuclear, aerospace, automotive, electronic and consumer products among other industries. Some of these applications exploit our complementary capabilities to model metal forming processes.

With specialised skills in the analysis of GRP, sandwich, honeycomb and other anisotropic composite materials, we have undertaken a range of projects in aerospace and other industries requiring strong, lightweight structures.

Our structural polymer capabilities are also supported by our injection moulding simulation experience.