Computational Finite Element Analysis Research Articles

Self-similar nesting strategy enables lattices achieve dual energy-absorbing plateaus

Inspired by natural self-similar nesting (SN) strategy, the basic truss unit simple cubic (SC), face centered cubic (FCC), and body centered cubic (BCC) were regenerated into novel architected SN units, aiming to achieve dual-plateaus and improved energy-absorbing capacity compared to basic truss units. Through compression experiments, finite element analysis, microstructure observation and theoretical calculation, the SN lattices were investigated to explore the influence of the nesting ratio on the compressive responses. The optimal nesting ratio was verified as 0.4 for the unit size of 8 mm and the relative density of 20%, enable SN-SC and SN-FCC achieve the stable and excellent energy absorption capabilities. Furthermore, the underlying mechanism of dual-plateau achieved by SN strategy was revealed that a SN unit can be zoned into a stronger region containing the nested core SC/FCC and a weaker region consisting of exterior nest SC/FCC and mediation BCC. The higher yield strength of the nested core SC/FCC compared to the exterior nest SC/FCC and BCC actually cause the second higher stress plateau and the better failure-resistance for the SN lattices. The improvement effect of SN strategy on SC and FCC units indicates that SN strategy has the potential to be applicable to various strut-based units.

A Simulation-Based Investigation on Thermal Responses of Suspension Bridge Tower Under Different Fire Scenarios

AbstractRecords of bridge fire incidents illustrate that bridge fires can have catastrophic consequences. The severity of these fires can be influenced by various factors such as bridge type, vehicle size, and wind. Contrary to building fires that have been extensively studied, scant attention has been paid to bridge fires and more specifically fire exposure to the suspension bridges. In addition, existing bridge fire literature is mostly concentrated on fire exposure to girders or cables of suspension bridges. Therefore, this study focused on the post-fire condition of a fire-exposed suspension bridge tower using computational fluid dynamics (CFD) modeling techniques and finite element analysis (FEA). The impacts of the main bridge fire parameters including vehicle size, exposure duration, distance between the fire source and tower, and wind effects were also evaluated. Initially, fire dynamic simulator (FDS) was used to simulate 12 different fire scenarios. The time–temperature histories obtained from each scenario were transferred to the ABAQUS finite element (FE) software to conduct transient thermal analysis and obtain the temperature development within the steel tower of the bridge. The post-fire evaluation was performed with respect to the temperature-induced reduction in the yield strength of steel. The results show that fire exposure from a fuel truck in the proximity of a steel tower could significantly reduce the strength of the tower and lead to severe damage. Early control of the fuel truck fire is crucial in reducing the severity of the damage and preventing temperature development in higher areas of the tower. Although a wind toward the tower can significantly increase the fire-induced damage to the bottom parts of the tower, it considerably reduces the temperature exposure to the higher parts of the tower. Fire exposure from a normal vehicle does not put the tower at risk of failure, and an unprotected steel tower can withstand it. However, a bus fire may lead to minor damage. The thermal strengthening of the first 20 m of the tower can help in preventing the potential fire damage.

Numerical Study on Hydrodynamic Performance of a Pitching Hydrofoil with Chordwise and Spanwise Deformation

The hydrofoil plays a crucial role in tidal current energy (TCE) devices, such as horizontal-axis turbines (HATs), vertical-axis turbines (VATs), and oscillating hydrofoils. This study delves into the numerical investigation of passive chordwise and spanwise deformations and the hydrodynamic performance of a deformable hydrofoil. Three-dimensional (3D) coupled fluid–structure interaction (FSI) simulations were conducted using the ANSYS Workbench platform, integrating computational fluid dynamics (CFD) and finite element analysis (FEA). The simulation involved a deformable hydrofoil undergoing pitching motion with varying elastic moduli. The study scrutinizes the impact of elastic modulus on hydrofoil deformation, pressure distribution, flow structure, and hydrodynamic performance. Coefficients of lift, drag, torque, as well as their hysteresis areas and intensities, were defined to assess the hydrodynamic performance. The analysis of the correlation between pressure distribution and deformation elucidates the FSI mechanism. Additionally, the study investigated the 3D effects based on the flow structure around the hydrofoil. Discrepancies in pressure distribution along the spanwise direction result from these 3D effects. Consequently, different chordwise deformations of cross-sections along the spanwise direction were observed, contributing to spanwise deformation. The pressure difference between upper and lower surfaces diminished with increasing deformation. Peak values and fluctuations of lift, drag, and torque decreased. This study provides insights for selecting an appropriate elastic modulus for hydrofoils used in TCE devices.

Experimental and numerical investigation on the hydroelastic response of barge and KVLCC2 ship

In this paper, the hydroelasticity of two segmented ship models (Barge and KVLCC2) is investigated by experimental and numerical methods. A two-way Computational Fluid Dynamics (CFD) and Finite Element Analysis (FEA) coupled method is adopted and further validated its accuracy against experimental results. The current approach emphasizes the overall convergence between two solvers, maintaining a strongly coupled manner to comprehensively address the fluid-structure interaction phenomenon, including the added mass effect. A series of experiments of a segmented Barge and KVLCC2 under various wave conditions were firstly conducted. The motions of the models are measured and the displacement Response Amplitude Operators (RAOs) are calculated. The CFD-FEA coupled method is demonstrated in agreement with experimental results by comparing the numerical prediction with the tank test results in terms of motion, affirming the validity and robustness. Finally, the hydroelastic response is discussed and investigated.

Modelling of aero-mechanical response of wind turbine blade with damages by computational fluid dynamics, finite element analysis and Bayesian network

Computational Fluid Dynamics and Finite Element Analysis structural models are developed for generation of large datasets of high-fidelity aerodynamic loading, displacement and stress for the NREL 5 MW wind turbine blade. Based on the datasets, analysis of structural responses of the turbine blade and their possible shifts with respect to a change in the operating conditions, e.g. rotor plane tilting and yawing, are performed. A Bayesian Network model is trained to produce ranges of values and likelihoods of occurrence of abnormal structural response or the most likely damage in the blade from inputs of operating conditions. The numerical analysis showed that yawing and tilting of rotor plane has very strong influence on the performance of a wind turbine. The out-of-plane bending is the dominant mode of the rotor blade while twisting and other complex modes of displacement could be more significant during some operating conditions such as at high tilt and yaw angles. The Bayesian Network is capable of computing probability mass functions of mechanical stress or displacement of the blade given a rotor rotation speed and a type of damage or vice versa, identifying a type of damage given a measured stress distribution level.

Simulation of Transient Temperature and Clearance after Shutdown of Aeroengine Based on CFD and FEA Coupled Models

It is crucial to comprehend the heat soak phenomenon, which may result in a significant temperature increase after the shutdown followed by a gradual decrease. This could bring potential risks for the engine including oil coking. The temperature change of engine components dictates the clearance after shutdown, while startup strategies are primarily based on this. A simulation strategy, utilizing computational fluid dynamics (CFD) and finite element analysis (FEA) coupled models, is suggested to investigate the transient temperature and clearance after shutdown. The maximum temperature deviation between the simulation result and experimental data are less than 6%. Flow parameters, including velocity and mass flow rate obtained from the CFD result, were applied as boundaries of the FEA model. Based on the FEA model, transient temperature calculations were also conducted for 20 hours after shutdown. The results indicate that the FEA model demonstrates good agreement with the CFD simulation, with a maximum deviation of less than 5% and at only 0.2% of the simulation time. After the engine shuts down, the stator’s temperature change rate is faster than that of the rotor due to better cooling conditions and relatively small heat capacity. Consequently, the seal clearance increases in the initial period after shutdown and then decreases to a minimum value. The nondimensional minimum clearance can be 0.8 times the cold state value at the location of the high-pressure turbine seal.

A ribbed strategy disrupts conventional metamaterial deformation mechanisms for superior energy absorption

ABSTRACT Enhancing energy absorption in mechanical metamaterials has been a focal point in structural design. Traditional methods often include introducing heterogeneity across unit cells. Herein, we propose a straightforward ribbed strategy to achieve exceptional energy absorption. We demonstrate our concept through modified body-centered cubic (BCC) and face-centered cubic (FCC) ribbed truss-lattice metamaterials (BCCR and FCCR). Using stainless-steel 316L samples, compression tests indicate a 111% and 91% increase in specific energy absorption (SEA) for BCCR and FCCR, respectively, along with an enhancement in compression strength by 61.8% and 40.7%. Deformation mechanisms are comprehensively elucidated through both finite element analysis and theoretical calculations. The mitigation of stress concentration at nodes, redistribution of load transfer pathways within struts, and introduction of multiple plastic hinges collectively contribute to increased energy absorption and higher compression strength. Using rein-based polymer samples, the ribbed truss-lattice metamaterials also exhibit exceptional damage tolerance, experiencing only a 15% loss in maximum strength after cyclic compression at 20% strain, while maintaining a 73% higher SEA compared to their non-ribbed counterpart. This strategy extends beyond the discussed structures, presenting itself as a generic approach to enhance plateau strength and SEA.

Finite element analysis and bearing capacity calculation of cross-shaped CFST columns under compressive load

The study investigated the load capacity of cross-shaped concrete-filled steel tubular (CFST) columns under axial and eccentric compression using finite element software ABAQUS. It analyzed six specimens with measured data and an additional 26 specimens with varied parameters, including eccentricity, slenderness ratio, section steel ratio and material properties such as concrete strength and steel yield strength.The objective was to understand how these parameters affect the load capacity of cross-shaped CFST columns. The research findings suggest that as eccentricity and slenderness ratio increase, the ultimate capacity decreases. Conversely, it increases with higher steel content, concrete strength and steel yield strength. Moreover, the bearing capacity deteriorates more rapidly with reduced eccentricity and concrete strength, while it demonstrates a nearly linear increase with greater steel content. Additionally, the study found that enhancing the resilience of the channel steel significantly boosts the load-bearing capacity of the column. Based on these findings, practical design equations were developed to determine the maximum bearing capacity of cross-shaped CFST columns under axial and eccentric compression. These equations are grounded in confined concrete theory and demonstrate robust applicability for practical design purposes.

Safety factor investigation based on finite element analysis in basement design using bamboo soil nailing

The use of retaining walls for basements in buildings generally uses the retaining wall that utilizes the weight of the wall itself as reinforcement because the reinforcement is carried out only on the soil’s surface. Using steel in soil nailing construction that is too large can result in the availability of steel running out, considering that steel is a non-renewable material. The soil nailing method in this paper uses bamboo as nails. The method used in this paper is the analytical method. Data bamboo material from the tests carried out in the Laboratory Building Materials Universitas Sebelas Maret Surakarta. While material data soil obtained from tests carried out at the Soil Mechanics Laboratory Sebelas Maret University, Surakarta. The analytical model is a basement excavation 10 m deep and 20 m wide. Finite element analysis calculations using the Plaxis 8.2 program on retaining walls. The analysis stages at each excavation depth of 2 m. The model obtained that the safety factor value is 4.271; this value is greater than the required safety factor value, namely FS 2, which indicates that soil stability achieve. The analysis results also obtained the achievement of soil stability at each stage of the research. There was no collapse of the bamboo during the analysis stage. The discussion results found that bamboo substitutes steel in soil nailing reinforcement as a retaining wall in basement construction.

Elastic Buckling Behavior of Functionally Graded Material Thin Skew Plates with Circular Openings

This study investigates the elastic buckling behavior of Functionally Graded Material (FGM) thin skew plates featuring a circular opening. FGMs, known for their unique property gradients, have gained prominence in structural engineering due to their mechanical performance and durability. Including a circular opening introduces a critical geometric consideration, influencing the structural stability and load-carrying capacity of FGM plates. The study examines the effects of the skew angle, plate’s aspect ratio, opening position, and size on the critical buckling load, normalized buckling load, and various buckling failure modes through computer modeling and finite element analysis. The results offer valuable insights into the interplay between material heterogeneity, geometric configuration, and structural stability. For instance, the critical buckling load increases by 29%, 82%, and 194% with an increment in skew angle from 0° to 30°, 45°, and 60°, respectively. Moreover, as the opening shifts from the plate’s edge closer to the center, the critical buckling load decreases by 26%. The critical buckling load is also dependent on the power index, as an increase in the power index from 0.2 to 5 reduced the buckling load by 1698 kN. This research contributes to the advancement of our understanding of FGM thin plates’ behavior under skew loading conditions, with implications for the design and optimization of innovative structures. The findings presented provide a foundation for further exploration of advanced composite materials and their applications in structural engineering.

Effect of Interfacial Modification on the Low-Temperature Fatigue Properties of Polymer/MXene Flexible Pressure Sensors.

Maintaining an excellent force-electric response under cyclic bending at low temperatures is still challenging for resistive-type electrically conductive polymer composite-based pressure sensors. In this study, the effect of low temperature on the fatigue failure of flexible MXene/polymer pressure sensors was systematically investigated through the silane functionalization of MXene nanosheets embedded with different polymer matrixes. The results show that the MXene/polymer interfaces are the primary factors affecting the temperature-dependent bending fatigue of the Cu/MXene/polymer/Cu sensor. Using finite element analysis and theoretical calculations, we reveal that the MXene/polymer interfaces are affected by free volume changes and the molecular chain motion under different temperatures. At room temperature, the well-distributed free volume in the polydimethylsiloxane (PDMS) matrix permits local segmental mobility that promotes the affinity between the polymer and MXene. As the temperature decreases, the free volume in the matrix shrinks with less space left for molecular chains to slide relatively, weakening the polymer/MXene interfacial bonding strength. However, for PDMS/MXene sensors with the interface modified using the silane coupling agent KH550, the nanoconstrained structure formed by strong hydrogen bonds and covalent bonds at the PDMS/MXene interface can hinder the mobility of polymer chains, which greatly helps to dissipate the inter/intrachain friction. It thus alleviates the debonding energy dissipation during cyclic bending at subzero temperatures.

3D micromechanical modeling of orthogonal hole saw cutting on CFRP composites

In the interest of developing a comprehensive understanding of the drilling process using the hole saw tool, this article aims to build a three-dimensional (3D) micromechanical model representing the orthogonal cutting of CFRP using one tooth of the hole saw tool. For this purpose, a finite element model is developed using Abaqus Explicit code. The influence of various drilling parameters like rake angle, inclination angle and cutting-edge radius on the drilling quality is explored. Especially, chip formation mechanisms, cutting force and lateral damage are analyzed. Through finite element simulations and computational analyses, it is found that these outputs results are highly influenced by drilling parameters. When the fiber orientation angle is set to 0°, increasing the rake angle results in a change in the chip formation mechanism from buckling to bending. In contrast, with a fiber orientation angle of 90°, bending and shear governs the chip formation process, irrespective of the rake angle. In both cases, whether the fiber orientation angle is 0° or 90°, chips tend to fragment more favorably with increasing the inclination angle. Regarding the cutting-edge radius, when the fiber orientation angle is 0°, an increase in the cutting-edge radius leads to a transition in the chip-forming mechanism from buckling to bending. However, for a fiber orientation angle of 90°, the chip formation remains governed by bending even as the cutting-edge radius changes. Decreasing the rake angle, the inclination angle, and the cutting-edge radius contribute to a reduction of the cutting force. As the inclination angle and the cutting-edge radius increase, the lateral damage increases, while the rake angle has showed a negligible impact on the damage. These results provide a guidance on the appropriate hole saw tool parameters for a good drilling quality namely, a rake angle of 20°, an inclination angle of 5° and a cutting-edge radius of 0.03 mm.

Retracted: Investigation of Utilizing Industrial Waste Residue Proportion on Concrete Structure: Computer Finite Element Analysis.

[This retracts the article DOI: 10.1155/2022/4483283.].

Моделирование эрозионного износа титанового сплава высокоскоростным потоком частиц

Introduction. Predicting solid particle erosion (SPE) in gaseous flow and managing its intensity is still a relevant problem in mechanical engineering. It requires the development of a general modeling methodology, which also depends upon many special cases studying various physical processes. Such studies should also include verification analysis, process parameters and model sensitivity studies. Mainly computational fluid dynamics and finite element analysis (and mesh-free methods such as smooth particle hydrodynamics or similar) are used to simulate the erosion process. Papers focused on CFD simulation of solid particle erosion of metal alloys are widely presented, but most of it is associated with relatively low or medium particle velocities (< 100–150 m/s) and is close to uniform diameter distribution. This paper presents a CFD study of Ti6Al4V titanium alloy SPE at relatively high particle velocities and sufficiently non-uniform unimodal particle diameter distribution. The paper also studies the turbulence model influence and particle shape effect which appears as a “shape factor” coefficient in the particle drag model. Methods. The heterogenous flow simulation was based on the Reynolds-averaged Navier-Stokes formulation, where the particles, according to Euler-Lagrange formulation, were simulated as mathematical points with corresponding properties. The influence of turbulence models, such as k-epsilon standard, RNG k-epsilon, and a relatively new Generalized equation k-omega (GEKO) model and its coefficients were also studied. Oka and DNV erosion models were also compared based on the general sample mass loss and more specific erosion intensity profile criterions. The simulation results were compared to the lab-scale experimental results. Results and discussion. It is shown that neither erosion intensity profile or sample mass loss do not depend upon the turbulence model choice or GEKO parameters variation. As expected, erosion is dependent on the erosion model and its coefficients. A notable influence of the shape factor is shown. As the drag coefficient increased due to the particle shape, the erosion intensity decreased and the erosive profile on the surface also changed due to the changing velocity and diameter distribution of the heterogenous flow. It is expected that such results would be useful not only for erosion prediction in all areas of mechanical engineering, but also for wear management in mechanical assemblies and shot peening / shot peen forming management and simulation.

CONTINUOUSLY CONTROLLABLE ARTIFICIAL DETRUSOR SYSTEM AND ITS CONTROL STRATEGY

In this paper, a new artificial detrusor system is proposed to achieve continuous control over the urination process and realize the normal voiding process of human (NVPH). The system is powered by a wireless power transfer (WPT) module, controlled by a control module and actuated by a shape memory alloy (SMA) spring. The design method of the SMA springs is proposed. Two control strategies are proposed to achieve NVPH. The first strategy is an open-loop control strategy based on the result of finite element analysis (FEM) simulation results and calculation of the derived system governing equations. The second strategy is a closed-loop control strategy based on the collection of feedback data and algorithmic processing. Both strategies are verified by experiments. The results show that the proposed system is feasible and both strategies can achieve NVPH. It can provide reference and guidance for the design of artificial detrusor system and formulation of control strategies.

Magnetic Coupling Effect and Performance Analysis of Dual Rotor Permanent Magnet Flux Switching Generator for Counter Rotating Wind Power Generation

To eliminate slip rings, brushes, and terminate gear-box mechanism, ferrite permanent magnet (PM) based counter rotating dual rotor PM flux switching generator (CRDRPMFSG) for direct drive counter rotating wind turbine (D <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> CRWT) application is proposed in this paper. Initially, the mechanism of gearless and brushless counter rotating wind power generation is discussed, and a simplified formulation opted for the slot/pole combinations. The proposed CRDRPMFSG encapsulate inner and outer machines with circumferentially magnetized PM enclosed by non-overlapped armature windings; thus, offering reduced overhang with compact design. However, co-axially linking the inner and outer machines through a shared stator yoke results in serious issues of magnetic coupling due to dual air-gap fields. To this end, eight topologies with various slot/pole combinations are comprehensively investigated using finite element analysis (FEA) for magnetic coupling effects and its influence on electromagnetic performance. From the analysis, it is shown that magnetic coupling level influence electromagnetic performance i.e., average torque, ripple rate, power factor, efficiency, losses, and output power. Moreover, it is noted that coupling level can be reduced by adopting same stator teeth in inner and outer machines or same stator teeth with different rotor poles. Finally, the predicted FEA calculations are verified experimentally with four benchmarked CRDRPMFSG prototypes.

Failure Analysis of Tubing Collapse in a Gas Well

The tubing used in a gas well rarely collapses and fails during applying annulus pressure. In this study, the failure causes of tubing collapse were analyzed by means of data verification, macroscopic observation, magnetic particle inspection, physical and chemical inspection, optical microscopy, and tubing collapse test. Mechanical analysis of the string and full-scale physical simulation test simulating downhole working conditions. Finally, the verification analysis of the collapse test is carried out by the finite element analysis (FEA). The results showed that (1) the physical dimension, physical and chemical properties, and collapse resistance of this batch of tubing met the requirements of the tubing ordering technical standard. (2) Assuming that the well packer slip was unsealed and could slide freely, the mechanical theoretical analysis of collapsed tubing string and collapse test under simulated working condition load was carried out, which reproduced the load when the tubing collapsed. It can be seen from this that the packer did fail. (3) The FEA calculation results showed that when the external pressure was greater than 30.75 MPa, it would inevitably lead to collapse failure in case of packer unsealed. In conclusion, the root cause for the collapse failure of the 105th underground tubing string was that the packer lost its sealing function, resulting in an abnormal axial load. While under the action of external pressure, the tubing was overloaded and collapsed. It is recommended to carry out verification tests on the material performance of packer slip, the dimensional changes of packer tool outer diameter and inner diameter under actual well conditions, the creep behavior of packer seal, and the performance of shear pin under actual working conditions, especially in the well containing H2S, so as to prevent the pressure leakage of gas well annulus caused by packer unsealing and the reoccurrence of such downhole string collapse accidents. The first collapse test under simulated working condition load is conducted in this paper. Analyzing the collapse failure work and putting forward suggestions to effectively prevent similar failures from happening again are of great significance to the oilfield.

Stress Corrosion Cracking Analysis of a Hot Blast Stove Shell with an Internal Combustion Chamber

The stress corrosion cracking during the operation of the internal combustion hot blast stove was analysed. The computational fluid dynamics and finite element analysis models were established to analyse the temperature, stress and other variables related to the condensation of the water and acids. The corrosion characteristics of condensation of acid and the stress corrosion cracking of the metallic shell of the hot blast stove during the operation were predicted by applying the fluid temperature and mapping it to the solid temperature. The stress corrosion cracking surface mobility mechanism was adopted and modified with a weight concept to consider the effect of the acid condensation and its concentration. The regions that have higher crack propagation rates were analysed. The influence of the increase in the blast temperature on the crack propagation rate was studied with the increase in the blast temperature by 45 K and 90 K from the reference blast temperature. The maximum temperature of the refractory linings was 1847 K in the on-gas period, and the maximum change in the shell temperature was 5.2 K when the blast temperature was increased by 90 K. The maximum crack propagation rate for the reference blast temperature was evaluated as 7.61×10−7 m/s. The maximum value of the crack propagation rate was increased by 16.7% when the blast temperature increased by 90 K. The conical region was found to have higher crack propagation rates, which means that the conical region should be the region of interest for managing the internal combustion hot blast stoves.

Numerical Investigations of Combustion Dynamics and Thermo-Mechanical Stress in the Ignition Assistance System for Small Aircraft Engines

ABSTRACT The utilization of ignition assistance devices offers an effective solution to overcome the challenges associated with ignition control in the development of propulsion systems for unmanned aerial vehicles (UAVs) that rely on sustainable aviation fuels. These devices actively control the combustion process to ensure successful ignition at different altitudes. The objective is achieved by introducing a controlled thermal energy deposit into the combustion chamber, mitigating potential ignition failures. This research presents a comprehensive analysis of the ignition characteristics and subsequent flame structure based on varying electric-circuit energy inputs, employing three-dimensional simulations. The ignition delay patterns are further examined from a fuel chemistry perspective, specifically focusing on the negative temperature coefficient (NTC). Additionally, this study introduces a strategic analysis of the thermo-mechanical stress experienced by the ignition assistance device when subjected to the impact of the spray-jet flame. To accomplish this, a coupled simulation approach combining computational fluid dynamics (CFD) and finite element analysis (FEA) is employed to analyze the transient wall stress. The parametric inputs obtained from the CFD simulations facilitate the FEA analysis, revealing critical mechanical-thermal stress accumulation on the heating element of the ignition assistance device.

Patient-specific computer modelling to predict anatomical risk factors preventing post transcatheter aortic valve implantation coronary re-access in bicuspid aortic valve; a modelling study

Abstract Background Post Transcatheter aortic valve implantation (TAVI) coronary re-access is predicted to become more common as TAVI expands into lower risk cohorts. The use of a self-expanding valve (SEV) has been recognised as an independent predictor for unsuccessful coronary cannulation. Other predictors include reduced transcatheter heart valve (THV) to coronary distance and small sino-tubular junction. Despite this however a patient cohort remains in which the use of a SEV is preferable due to anatomical complexity or extensive calcification. Purpose Using patient-specific computer modelling, we aimed to assess how the deployment of different sized THVs and at different depths affected the distance from valve to coronary and valve to sino-tubular junction in bicuspid aortic valve cases. Methods In this modelling study we have used pre-procedural, CT-derived, patient-specific finite element analysis computer models to predict the eventual valve result. We studied two anatomical measures for both right and left coronary sinuses. The distance from coronary ostium to nearest structure, either THV or displaced native leaflet – Sinus of Valsalva (SoV) free space. The second distance was from the STJ to THV – STJ free space. THVs were modelled at both high and medium implant positions. THV size was based upon annular dimensions. Where the annular dimensions fell near an anatomical grey-zone, a second size THV was modelled. For each patient and measure, a mean of all distances was calculated, in addition to both minimum and maximum distances. Results The free space SOV left main coronary artery (LMCA) mean was 6.39 mm (4.87-7.91 mm). The difference between maximum and minimum was 0.9461 mm (0.54–1.36 mm), p&amp;lt;0.01. The largest patient-specific difference between minimum and maximum was 2.41 mm, using the same THV size but at different depths. The free space SOV right coronary artery (RCA) mean was 5.73 mm (4.17-7.30 mm). The difference between maximum and minimum was 0.789 mm (0.49-1.09 mm), p&amp;lt;0.01. The STJ free space LMCA mean was 4.3 mm (2.35–6.27 mm), The difference between maximum and minimum was 0.99 mm (0.63-1.35 mm), p&amp;lt;0.01. The STJ free space RCA mean was 3.76 mm (2.2-5.32 mm).The difference between maximum and minimum was 1.18 mm (0.9-1.56 mm), p&amp;lt;0.01. The largest patient-specific difference between minimum and maximum was 2.02 mm, using the same valve size but at different depths. Data presented as mean (95% confidence intervals), n=16 patients/48 models. Conclusions This modelling study has indicated a significant difference in all four measured parameters when different THVs are modelled at different depths. Note some of the largest differences are seen with the same size THV but at a different depth. We would highlight the small mean effect size seen across the results, however in cases where the difference is &amp;gt;2mm, this could have an effect on coronary re-access and warrants further investigation.