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At least 1,621 records · Page 90
All sourcesNASA NTRSDOE OSTI
DOE OSTI2021

Empirical prediction of saline water atomization pressure loss and spray phase change using local flow pressure analysis

A pressure analysis technique was developed to obtain spray spatial evaporation profile in a thermal desalination process. The technique can replace temperature-based evaporation measurement methods that are challenged by liquid-phase interference. It also provides an alternative to optical methods with high cost and complexity. Fundamental analysis was developed to determine local humidity ratios from changes in local static and dynamic pressures. The analysis was applied to data obtained from an external mixing air-assist atomizer. An empirical model was developed for the pressure loss in atomization process and was used in the analysis of humidity ratio. The results were used to develop empirical correlations for local humidity ratio in spray mediums using inlet conditions. Utilizing inlet conditions to predict evaporation profiles is an important contribution as it eliminates the need to take local spray measurements. Obtaining local data is often difficult and expensive; Our method and correlation circumvent the need for that. Finally, the correlations presented in this paper apply to saline water sprays with total dissolved salt of 0-10 wt%. The salinity-specific correlations are accurate to within ±10% of experimental data. The individual models were aggregated into a unified correlation for salinities within 0-10 wt%. The unified correlation is accurate to within ±18% of experimental data.

42 ENGINEERING↗
DOE OSTI2017

A Preliminary Assessment of the SURF Reactive Burn Model Implementation in FLAG

Properly validated and calibrated reactive burn models (RBM) can be useful engineering tools for assessing high explosive performance and safety. Experiments with high explosives are expensive. Inexpensive RBM calculations are increasingly relied on for predictive analysis for performance and safety. This report discusses the validation of Menikoff and Shaw’s SURF reactive burn model, which has recently been implemented in the FLAG code. The LANL Gapstick experiment is discussed as is its’ utility in reactive burn model validation. Data obtained from pRad for the LT-63 series is also presented along with FLAG simulations using SURF for both PBX 9501 and PBX 9502. Calibration parameters for both explosives are presented.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2018

An Experimental Investigation of Fuel Staging In A Model Gas Turbine Combustor

Modern gas turbine engines are typically operated in a lean-premixed configuration in order to meet emissions requirements. Lean operation makes gas turbines more susceptible to combustion instability, which can cause catastrophic hardware failure if left unchecked. The spatially uneven distribution of fuel in a gas turbine combustor, known as fuel staging, is an effective way of suppressing instabilities. This dissertation examines the effect of both steady-state and transient fuel-staging in a model gas turbine combustor. First, the steady-state effect of fuel staging on nominally unstable operating conditions is examined. At 200 degrees Celsius and a bulk flow velocity of 26 m/s, the combustor undergoes self-excited instabilities when the equivalence ratio is between φ = 0.70 and φ = 0.74 when all nozzles are fueled equally. These instabilities are suppressed when the center nozzle equivalence ratio is increased to φ Staging = 0.85 and the outer nozzle equivalence ratio maintained at φ = 0.70 or when the global equivalence ratio is maintained at φ = 0.70 by increasing the center nozzle equivalence ratio to φ Staging = 0.74 and decreasing the outer nozzle equivalence ratio to φ Staging = 0.69. The staged p' RMS amplitudes are found to decrease with increasing equivalence ratio and the damping rates found to increase with increasing equivalence ratio. Next, axisymmetric fuel staging transients are conducted valve opening/closing timescales of 1, 16, 58, 4,000, and 10,000 ms, and equivalence ratios of φ staging = 0.75, 0.80, 0.85. It should be noted that these valve opening/closing timescales, referred to as τ Transient , differ from the actual fuel convection timescale that are summarized in Table 5.2. It is found that the combustor pressure fluctuation at the end of the transient strongly depends on staging equivalence ratio but not on τ Transient . Increasing the staging equivalence ratio decreased the staged- stable combustor pressure amplitude, similarly to the steady-state results. The staged-stable damping rate trends are insensitive to to τ Transient and increased with increasing staging equivalence ratio. The timescale of the transition, τ, is found to be sensitive to both τ Transient and the staging equivalence ratio. For a Modern gas turbine engines are typically operated in a lean-premixed configuration in order to meet emissions requirements. Lean operation makes gas turbines more susceptible to combustion instability, which can cause catastrophic hardware failure if left unchecked. The spatially uneven distribution of fuel in a gas turbine combustor, known as fuel staging, is an effective way of suppressing instabilities. This dissertation examines the effect of both steady-state and transient fuel-staging in a model gas turbine combustor. First, the steady-state effect of fuel staging on nominally unstable operating conditions is examined. At 200 degrees Celsius and a bulk flow velocity of 26 m/s, the combustor undergoes self-excited instabilities when the equivalence ratio is between φ = 0.70 and φ = 0.74 when all nozzles are fueled equally. These instabilities are suppressed when the center nozzle equivalence ratio is increased to φ Staging = 0.85 and the outer nozzle equivalence ratio maintained at φ = 0.70 or when the global equivalence ratio is maintained at φ = 0.70 by increasing the center nozzle equivalence ratio to φ Staging = 0.74 and decreasing the outer nozzle equivalence ratio to φ Staging = 0.69. The staged p' RMS amplitudes are found to decrease with increasing equivalence ratio and the damping rates found to increase with increasing equivalence ratio. Next, axisymmetric fuel staging transients are conducted valve opening/closing timescales of 1, 16, 58, 4,000, and 10,000 ms, and equivalence ratios of φ staging = 0.75, 0.80, 0.85. It should be noted that these valve opening/closing timescales, referred to as τ Transient , differ from the actual fuel convection timescale that are summarized in Table 5.2. It is found that the combustor pressure fluctuation at the end of the transient strongly depends on staging equivalence ratio but not on τ Transient . Increasing the staging equivalence ratio decreased the staged-stable combustor pressure amplitude, similarly to the steady-state results. The staged-stable damping rate trends are insensitive to to τ Transient and increased with increasing staging equivalence ratio. The timescale of the transition, τ, is found to be sensitive to both τ Transient and the staging equivalence ratio. For a Modern gas turbine engines are typically operated in a lean-premixed configuration in order to meet emissions requirements. Lean operation makes gas turbines more susceptible to combustion instability, which can cause catastrophic hardware failure if left unchecked. The spatially uneven distribution of fuel in a gas turbine combustor, known as fuel staging, is an effective way of suppressing instabilities. This dissertation examines the effect of both steady-state and transient fuel-staging in a model gas turbine combustor. First, the steady-state effect of fuel staging on nominally unstable operating conditions is examined. At 200 degrees Celsius and a bulk flow velocity of 26 m/s, the combustor undergoes self-excited instabilities when the equivalence ratio is between φ = 0.70 and φ = 0.74 when all nozzles are fueled equally. These instabilities are suppressed when the center nozzle equivalence ratio is increased to φ Staging = 0.85 and the outer nozzle equivalence ratio maintained at φ = 0.70 or when the global equivalence ratio is maintained at φ = 0.70 by increasing the center nozzle equivalence ratio to φ Staging = 0.74 and decreasing the outer nozzle equivalence ratio to φ Staging = 0.69. The staged p' RMS amplitudes are found to decrease with increasing equivalence ratio and the damping rates found to increase with increasing equivalence ratio. Next, axisymmetric fuel staging transients are conducted valve opening/closing timescales of 1, 16, 58, 4,000, and 10,000 ms, and equivalence ratios of φ staging = 0.75, 0.80, 0.85. It should be noted that these valve opening/closing timescales, referred to as τ Transient , differ from the actual fuel convection timescale that are summarized in Table 5.2. It is found that the combustor pressure fluctuation at the end of the transient strongly depends on staging equivalence ratio but not on τ Transient . Increasing the staging equivalence ratio decreased the staged- stable combustor pressure amplitude, similarly to the steady-state results. The staged-stable damping rate trends are insensitive to to τT Transient and increased with increasing staging equivalence ratio. The timescale of the transition, τ, is found to be sensitive to both τ Transient and the staging equivalence ratio. For a given τ Transient , the decay timescale decreased with increasing staging equivalence ratio. For 1, 16, and 58 ms transients, τ does not depend on τ Transient , though it does strongly depend on direction, where instability onset cases have longer and more variable τ than instability decay cases. The same dependence of τ on direction is seen for the 4,000 and 10,000 ms transients. However, unlike the short duration transients, τ does depend on τ Transient as would be expected. Phase space reconstruction shows the instability is a harmonic limit cycle with a single frequency. The instantaneous phase images shows the center region of the combustor goes out-of-phase first followed by the rest of the combustor. Finally, asymmetric fuel staging tests are conducted. It is found that non-axisymmetric staging can be as effective as axisymmetric staging, although small hardware variations between nozzles can affect the the minimum staging equivalence ratio that consistently suppresses the instability. These changes in the bifurcation equivalence ratio can make staging configurations appear less effective; however, both axisymmetric and non-axisymmetric staging configurations exhibit similar staged-stable p' RMS , damping rates, and instability transition times for equivalence ratios greater than the bifurcation equivalence ratio. Instantaneous phase images show similar instantaneous phase relationship structures in the staged nozzle (center or outer), suggesting that the instability suppression mechanism is similar in each case. This result is surprising given that the time-averaged flame shapes are very different between axisymmetric and non-axisymmetric staging configurations. The similar effectiveness of axisymmetric and non-axisymmetric staging in this geometry is attributed to the fact that the instability mode is a nominally axisymmetric plane wave. It is hypothesized that non-axisymmetric staging configurations will likely be more effective than axisymmetric staging configurations when the instability mode shape is asymmetric (such as a circumferential wave).

Culler, Wyatt↗
DOE OSTI2016

Energy and emissions saving potential of additive manufacturing: the case of lightweight aircraft components

Additive manufacturing (AM) holds great potential for improving materials efficiency, reducing life-cycle impacts, and enabling greater engineering functionality compared to conventional manufacturing (CM), and AM has been increasingly adopted by aircraft component manufacturers for lightweight, cost-effective designs. This study estimates the net changes in life-cycle primary energy and greenhouse gas emissions associated with AM technologies for lightweight metallic aircraft components through the year 2050, to shed light on the environmental benefits of a shift from CM to AM processes in the U.S. aircraft industry. A systems modeling framework is presented, with integrates engineering criteria, life-cycle environmental data, aircraft fleet stock and fuel use models under different AM adoption scenarios. Estimated fleet-wide life-cycle primary energy savings at most reach 70-173 million GJ/year in 2050, with cumulative savings of 1.2–2.8 billion GJ. Associated cumulative GHG emission reductions were estimated at 92.1–215.0 million metric tons. In addition, thousands of tons of aluminum, titanium and nickel alloys could be potentially saved per year in 2050. The results indicate a significant role of AM technologies in helping society meet its long-term energy use and GHG emissions reduction goals, and highlight barriers and opportunities for AM adoption for the aircraft industry.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2024

Library of Advanced Materials for Engineering (LAMÉ) 5.20

Accurate and efficient constitutive modeling remains a cornerstone issue for solid mechanics analysis. Over the years, the LAMÉ advanced material model library has grown to address this challenge by implementing models capable of describing material systems spanning soft polymers to stiff ceramics including both isotropic and anisotropic responses. Inelastic behaviors including (visco)plasticity, damage, and fracture have all incorporated for use in various analyses. This multitude of options and flexibility, however, comes at the cost of many capabilities, features, and responses and the ensuing complexity in the resulting implementation. Therefore, to enhance confidence and enable the utilization of the LAMÉ library in application, this effort seeks to document and verify the various models in the LAMÉ library. Specifically, the broader strategy, organization, and interface of the library itself is first presented. The physical theory, numerical implementation, and user guide for a large set of models is then discussed. Importantly, a number of verification tests are performed with each model to not only have confidence in the model itself but also highlight some important response characteristics and features that may be of interest to end-users. Finally, in looking ahead to the future, approaches to add material models to this library and further expand the capabilities are presented.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Enhancing 2D hydrodynamic flood models through machine learning and urban drainage integration

Two-dimensional hydrodynamic flood models are commonly employed for simulating flood extent and inundation depth. However, the influence of urban drainage network (UDN) is frequently overlooked in these models, potentially compromising their accuracy. Furthermore, the expensive computational costs and longer processing times make them challenging for large-scale hydrodynamic simulation. To address these challenges, this paper develops a machine learning (ML)-driven emulator for an open-source flood model, the Two-dimensional Runoff Inundation Toolkit for Operational Needs (TRITON). A TRITON-ML Emulator (TR-Emulator) that utilizes Convolutional Long Short-Term Memory is developed to capture the spatiotemporal features of flood events based on the outputs from TRITON. We further enhance the emulator by integrating UDN parameters (TR-UDN), such as the flow capacity of drainage pipes, pipe size, and pipe length, via an ML stacking technique to improve the water surface elevation (WSE) simulation. Hurricane Harvey 2017 in Houston, TX is used as the case study. We compare WSE results from TRITON, TR-Emulator, TR-UDN, and the United States Geological Survey (USGS) observations to evaluate the performance of these models. The results indicate that the TR-Emulator effectively replicates the WSE simulated by TRITON. Additionally, TR-UDN performs well in capturing WSE patterns and peak flows, aligning more closely with USGS observations, except in areas with milder slopes where conveyance discrepancies are observed. We further test the generalizability of our ML-based models using another smaller event. This paper shows that the TR-Emulator is effective for users and engineers to emulate a 2D hydrodynamic model, and the enhanced version of the TR-Emulator, TR-UDN, can be an efficient tool for predicting WSEs during urban flooding.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2022

Computer Model Calibration with Time Series Data Using Deep Learning and Quantile Regression

Computer models play a key role in many scientific and engineering problems. One major source of uncertainty in computer model experiments is input parameter uncertainty. Computer model calibration is a formal statistical procedure to infer input parameters by combining information from model runs and observational data. The existing standard calibration framework suffers from inferential issues when the model output and observational data are high-dimensional dependent data, such as large time series, due to the difficulty in building an emulator and the nonidentifiability between effects from input parameters and data-model discrepancy. To overcome these challenges, we, in this work, propose a new calibration framework based on a deep neural network (DNN) with long short-term memory layers that directly emulates the inverse relationship between the model output and input parameters. Adopting the “learning with noise” idea, we train our DNN model to filter out the effects from data-model discrepancy on input parameter inference. We also formulate a new way to construct interval predictions for DNN using quantile regression to quantify the uncertainty in input parameter estimates. Through a simulation study and real data application with the Weather Research and Forecasting Model Hydrological modeling system (WRF-Hydro), we show our approach can yield accurate point estimates and well-calibrated interval estimates for input parameters.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2019

Surface Engineering by Simultaneous Action of Multiple External Fields (Final Technical Report)

This research project aims at enabling surface engineering strategies based on the fundamental understanding and predictive modeling of the surface morphological response of solid materials subjected to the combined action of multiple external forces. Surface morphological response to mismatch strain in strained-layer heterostructures also is analyzed. Our research focuses on the surface morphological evolution and stability of electrically conducting (metallic, such as Cu) and semiconducting (such as Si) solids under the simultaneous application of mechanical stresses, electric fields, and temperature gradients. We emphasize on identifying the conditions under which the multiply driven surface morphology is stable and on exploring the complexity of the corresponding various morphologically stable surface patterns. We also emphasize on the driven evolution of nanoscale features aiming at stabilizing and controlling nanoscale patterns on surfaces by their manipulation through simultaneously applied multiple external forces. Specifically, we address systematically the morphological response to the combined action of multiple external forces of bulk solid surfaces, surfaces of thin films grown epitaxially on thick or thin substrates, as well as nanoscale surface features such as coherently strained islands grown epitaxially on substrate surfaces. The research is based on a modeling approach that combines theoretical analyses of surface morphological stability with self-consistent dynamical simulations of surface evolution based on properly parameterized continuum and multiscale surface transport models.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Effects of Port Angle on Scavenging of an Opposed Piston Two-Stroke Engine

Opposed-piston 2-stroke (OP-2S) engines have the potential to achieve higher thermal efficiency than a typical diesel engine. However, the uniflow scavenging process is difficult to control over a wide range of speeds and loads. Scavenging performance is highly sensitive to pressure dynamics, port timings, and port design. This study proposes an analysis of the effects of port vane angle on the scavenging performance of an opposed-piston 2-stroke engine via simulation. A CFD model of a three-cylinder opposed-piston 2-stroke was developed and validated against experimental data collected by Achates Power Inc. One of the three cylinders was then isolated in a new model and simulated using cycle-averaged and cylinder-averaged initial/ boundary conditions. This isolated cylinder model was used to efficiently sweep port angles from 12 degrees to 29 degrees at different pressure ratios. Results indicate that scavenging performance is correlated with the bulk swirl ratio generated by these port angles. Scavenging performance is also sensitive to the pressure ratio across the engine. It was concluded that, for a given pressure ratio, the smallest port angle produces the best scavenging; however, previous work indicates lower bulk swirl ratio during combustion can have an impact on emissions formation.

33 ADVANCED PROPULSION SYSTEMS↗
DOE OSTI2021

Formulation and calibration of two-dimensional constitutive models for composite structures based on panel tests

Steel Plate Concrete (SC) composite members have been widely adopted because of its cost-efficiency and enhanced structural behavior. While researchers have attempted to study its in-plane shear behavior in the past twenty years, very limited number of large-scale pure shear tests were performed due to the challenge of experimental set-up and the availability of facilities. In this paper, a series of uniaxial loading tests and two full-scale pure shear panel tests of SC members were reported, on which the “mechanics-based Membrane Model of SC elements (MM-SC)” is developed. The MM-SC model is based on the fixed-angle crack formulation and the smeared-crack formulation, in which the experimental-based uniaxial constitutive models are implemented, considering the local buckling of faceplate, the tension stiffening of steel plate, the strength degradation of cracked concrete and the confinement effect of concrete. The proposed MM-SC model is subsequently incorporated into the object-oriented software OpenSEES. Finally, the simulation results of proposed model well predict the SC test observations in terms of critical branch points and structural behaviors, including initial stiffness, cracking strength, post-crack stiffness, yield strength, maximum strength, and failure modes.

42 ENGINEERING↗
DOE OSTI2021

Power System Modeling for the Study of High Penetration of Distributed Photovoltaic Energy

Many conventional power systems are evolving due to the growth of renewable energy and distributed energy resources (DERs). Modeling the interplay of transmission and distribution systems is critical to analyze how DERs impact a system’s conventional operation and which electric infrastructure improvements are needed to achieve a balance between centralized generation and DERs. This article describes the process, tools, and resources used to model electric power systems with a centralized infrastructure in an isolated context and limited access to actual utility data. Photovoltaic systems installed on residential rooftops were the main design option. This work broadened the typical power system modeling to include planning and social considerations. This integrative engineering-social method allows for interdisciplinary teams to work in the development of a model as part of broader design goals for a renewable-dominant energy system. The Puerto Rico electric power system was used as a case study to demonstrate the process. The integrative engineering-social perspective in developing the model and the actions to manage data limitations are aspects that could be followed in other locations with aggressive renewable energy goals and where utility data are not readily available.

Cuello-Polo, Gustavo↗
DOE OSTI2021

The Corrected Distortion model for Lagrangian spray simulation of transcritical fuel injection

In this work, we present a detailed implementation and validation of the droplet modeling framework proposed by Dahms and Oefelein (2016) into the engine commercial CFD software CONVERGE using the User Defined Function (UDF) interface. The model accounts for the nonlinear deformation and oscillation experienced by liquid spray droplet injected into high pressure and temperature. Lagrangian spray simulations of Engine Combustion Network (ECN) Spray A are performed. Model validation against standard experimental measurements of liquid velocity, vapor mixture fraction is conducted. To perform more rigorous model validation, new experimental measurements based on Diffused Back Illumination (DBI) are introduced. The new measurements are processed for Projected Liquid Volume (PLV), which offers as close as possible one-to-one model validation for liquid penetration while offering new insights into the spray physics. Comparison with a One-D model based on adiabatic mixing theory by Siebers (1999) and Desantes et al. (2007) are also conducted. Through these model validation exercises, it is shown that the new framework improves liquid-phase penetration predictions, following a tendency for enhanced evaporation, compared to the standard approach for both Reynolds Average Navier Stokes (RANS) and Large Eddy Simulation (LES). Additionally, at the liquid length, maximum mixture fraction values predicted by the new approach are in good agreement those of an adiabatic mixing model. Qualitative analysis of the spray behaviors during the early stage of the injection process reveals that the proposed framework predicts significant increase in droplet evaporation rate with lower drop drag compared to the current standard approach.

42 ENGINEERING↗
DOE OSTI2022

Estimation of China Fusion Engineering Test Reactor performance and burning fraction in different pellet fueling scenarios by a multi-species radial transport model

Tritium self-sufficiency in future deuterium–tritium fusion reactors is a crucial challenge. As an engineering test reactor, the China Fusion Engineering Test Reactor requires a burning fraction of 3% for the goal to test the accessibility to the future fusion plant. To self-consistently simulate burning plasmas with profile changes in pellet injection scenarios and to estimate the corresponding burning fraction, a one-dimensional multi-species radial transport model is developed in the BOUT++ framework. Here several pellet-fueling scenarios are then tested in the model. The results show that the increased fueling depth improves the burning fraction by particle confinement improvement and fusion power increase. Nevertheless, by increasing the depth, the pellet cooling-down may significantly lower the temperature in the core region. Taking the density perturbation into consideration, the reasonable parameters of the fueling scenario in these simulations are estimated as pellet radius ${r}_{{\rm{p}}}=3\,{\rm{mm}},$ injection rate $=\,4\,\mathrm{Hz},$ and pellet injection velocity $=\,1000\mbox{-}2000\,{\rm{m}}\,{{\rm{s}}}^{-1}$ without drift or $450\,{\rm{m}}\,{{\rm{s}}}^{-1}$ with high-field-side drift.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2019

Utah FORGE: 3D Gravity Data

These resources describe the 3D geophysical inversion modeling of gravity data at the FORGE site near Milford, Utah. FORGE is the Frontier Observatory for Research in Geothermal Energy and the site in Utah has been selected by the U.S. Dept. of Energy for a 5-year R&D program to test technologies for the development of Engineered Geothermal Systems (EGS). 3D modelling of gravity data at the FORGE site is to help characterize the subsurface geologic framework. Specifically, modelling of gravity data in 3D, used in conjunction with rock density measurements and other subsurface geologic information can provide an independent test of an existing 3D geologic model (e.g. Witter et al., 2018). Such an exercise can be useful for reducing uncertainty in 3D geologic models (Witter et al, 2019).

15 GEOTHERMAL ENERGY↗
DOE OSTI2015

Comparison of Two Models for Damage Accumulation in Simulations of System Performance

A comprehensive simulation study of system performance needs to address variations in component behavior, variations in phenomenology, and the coupling between phenomenology and component failure. This paper discusses two models of this: 1. damage accumulation is modeled as a random walk process in each time history, with component failure occurring when damage accumulation reaches a specified threshold; or 2. damage accumulation is modeled mechanistically within each time history, but failure occurs when damage reaches a time-history-specific threshold, sampled at time zero from each component’s distribution of damage tolerance. A limiting case of the latter is classical discrete-event simulation, with component failure times sampled a priori from failure time distributions; but in such models, the failure times are not typically adjusted for operating conditions varying within a time history. Nowadays, as discussed below, it is practical to account for this. The paper compares the interpretations and computational aspects of the two models mentioned above.

42 ENGINEERING↗
DOE OSTI2018

A computational thrombus formation model: application to an idealized two-dimensional aneurysm treated with bare metal coils

Cardiovascular implantable devices alter the biofluid dynamics and biochemistry of the blood in which they are placed. These perturbations can lead to thrombus formation which may or may not be desired, depending on the application. In this work, a computational model is developed that couples biofluid dynamics and biochemistry to predict the clotting response of blood to such devices. The model consists of 28 advection–diffusion–reaction partial differential equations to track proteins in the blood involved in clotting and utilizes boundary flux terms to model the initiation of the intrinsic clotting pathway at thrombogenic device surfaces. We use this model to simulate the transient clot growth within a 2D idealized bifurcation aneurysm filled with various distributions of bare metal coils with similar packing densities. The clot model predicts initial clot formation to occur in areas along coil surfaces where flow is minimal and where time-averaged shear rates are the smallest. Among the six coil-filled aneurysm cases simulated, maximum thrombus occlusion ranged between 80.8 and 92.2% of the post-treatment aneurysm volume and was achieved 325–450 s after treatment. Finally, with further refinement and validation, the computational clotting model will be a valuable engineering tool for evaluating and comparing the relative performance of cardiovascular implantable devices.

60 APPLIED LIFE SCIENCES↗