Inlet Boundary Research Articles

Integration of atmospheric stability in wind resource assessment through multi-scale coupling method

The abundance level of wind resources is the first and most important factor to consider in the wind farm design. The accuracy of wind energy resource assessment directly determines the operating income of a wind farm after its construction is completed. Therefore, aiming to meet the requirements of accurate wind resource assessment in areas with a complex terrain or those lacking the observation information, this paper proposes a multi-scale coupling numerical simulation method based on atmospheric stability. First, the atmospheric flow field simulation results at the heights of 200 m, 300 m, and 400 m are extracted from the mesoscale Weather Research and Forecasting (WRF) model and used as inlet boundary conditions of a microscale Computational fluid dynamics (CFD) model. Then, to obtain more accurate coupling data at the height of a wind turbine hub, the atmospheric stability parameter is introduced into the multi-scale coupling process, data correction is conducted at the three heights, and a comparison with the observation data of a wind tower is made. Finally, a numerical analysis is conducted using real data of a wind farm in eastern Inner Mongolia and Jilin. The analysis results show that the proposed method can improve the assessing accuracy of wind resources of wind farms using mesoscale data, which is valuable to a certain extent in real-world applications.

MATHEMATICAL MODELING OF SARS-COV-2 PARTICLES’ PROPAGATION DURING HUMAN REFLEXES

An unknown virus, which was detected in Wuhan city in 2019, had changed fate of the world immediately causing an economic loss, decrease in total population and etc. A penetration of coronavirus contaminated particles to a human cell is able to cause an overproduction of cytokines and antibodies. This process gives a rise to fatal cases. Hence, because of SARS-CoV-2’s pathogenicity, severity and unexpectedness, effective safety measures should be implemented. Along with safe social distancing and wearing a mask, a presence of air conditioning, ventilation system and open windows can reduce the coronavirus propagation in enclosed spaces. The present article focuses on the modeling of coronavirus particles’ propagation during human respiratory reflexes within a constructed three-dimensional confined space with inlet and outlet boundary conditions. Momentum and continuity equations, k-ε turbulence model and Lagrangian dispersion model were utilized to solve the problem. SIMPLE is a main method to solve all governing equations. The primary objectives of this work are to demonstrate the efficiency of air conditioning and open windows in preventing the spread of viruses and to examine particle behavior in the computational domain.

Indoor airflow field reconstruction using physics-informed neural network

Obtaining a detailed indoor airflow field is important for the accurate and efficient control of indoor environmental comfort. Traditional computational fluid dynamics (CFD) methods and CFD-based surrogate models are time-consuming and sometimes produce inaccurate results because of difficulties in reproducing accurate inlet boundary conditions. Artificial neural networks (ANN) can be utilized to reconstruct indoor airflow fields directly from measurement data without building a large inaccurate and time-consuming CFD database. However, as a purely data-driven method, a normal ANN can yield unphysical results. A physics-informed neural network (PINN) is one possible solution. In this study, a PINN was introduced to reconstruct an indoor airflow field basing on measurement data (without inlet boundary conditions), and compared with ANN. The results show that the PINN produced more physical results than the ANN and is more tolerant to a reduction in the number of measurement points. In specific cases, the mean errors of the PINN results for the 98-, 32, and 16 point cases were 89%, 79%, and 70% of those of the ANN results, respectively. The PINN showed practical application potential in cases where the amount of measured data was relatively small. Comparing to traditional CFD, PINN can reconstruct the detailed airflow field directly from measurement data, avoiding inaccurate simulation conditions. Meanwhile, PINN saved 42% calculation time, comparing to CFD. Moreover, there is a potential of PINN in using less time to apply a trained PINN to a new case by transfer learning, where however CFD needs to recalculate a new case.

A novel combined model for energy consumption performance prediction in the secondary air system of gas turbine engines based on flow resistance network

Predicting the comprehensive energy consumption is challenging for the complicated secondary air system. To solve this problem, a universal flow resistance element has been constructed to describe different components more accurately. And a novel flow resistance network is proposed to calculate the system's energy consumption. This network can be analyzed by the flow resistance characteristics of its components to estimate the energy consumption of each component and the energy loss of the system. Furthermore, a flow resistance parameter is defined as a unique factor to determine the magnitude of flow resistance for each component. Compared to experimental and numerical results, both models demonstrate sufficient accuracy in calculating mass flow rates and entropy increments, with the maximum deviation less than 1.2%. The above two models are also applied to predict flow losses of elements with changes in pressure and inlet total temperature, with the maximum deviation less than 4.5%. Based on the flow resistance network, the aerodynamic performance of each element can be easily computed by the inlet and outlet boundary of this system, regardless of whether the elements are arranged in series or parallel.

Effects of Boundary Conditions on Performance Prediction of Deep-Buried Ground Heat Exchangers for Geothermal Energy Utilization

An accurate prediction for deep-buried ground heat exchangers (DBGHEs) is the premise for efficient utilization of geothermal energy. Due to the complexity of the geological composition spanning thousands of meters, the configuration of boundary conditions plays a critical role in evaluating DBGHE thermal performance. This paper proposed a three-dimensional model of full-scale DBGHE involving both conductive and convective heat transfer in aquifuge and aquifer layers. The constant inlet temperature and constant heating power boundaries in the DBGHE domain, and the surface–bottom temperature and heat flux boundaries in the rock-soil domain were examined. It was found that the differences in the performance prediction caused by different DBGHE boundary conditions were closely related to the system’s operating time. The relative differences in heat extraction amount and average borehole temperature of 2000 m DBGHE caused by the two inlet boundaries on the 30th day were, respectively, 19.5% and 18.3%, while these differences on the 120th day were decreased to 8.4% and 9.9%, respectively. It was found that the constant inlet temperature boundary was more appropriate than the constant heating power condition for estimating aquifer effects on the performance of DBGHE. For the rock-soil domain, the results showed that the heat extraction amount of DBGHE under the heat flux boundary was 12.6%–13.6% higher than that under the surface–bottom temperature boundary. Particularly, when considering the velocity change of groundwater in the aquifer, the relative difference in heat extraction amount increments caused by the two types of rock-soil boundaries can reach 26.6% on the 120th day. It was also found that the thermal influence radius at the end of a heating season was hardly affected by either the DBGHE inlet or rock-soil domain boundary conditions.

Instabilities identification based on a new centrifugal 3D impeller outflow model

Previous research works have shown that the inflow boundary conditions have a significant effect on the behavior of diffusers in a centrifugal machine. To better understand the vaneless diffuser instability mechanism and save computing resources, several numerical works are planned to be conducted for the solely vaneless diffuser, excluding the rest of the centrifugal machine from the flow domain to simulate. Previous reduced-order models used either two-dimensional approaches that focused exclusively on the core-flow instability or three-dimensional models tested for a few inflow conditions. To obtain the more realistic diffuser inlet boundary conditions, a modeling method is here developed by fitting the diffuser inflow velocity derived from numerical simulations of the entire machine. The classic fitting methods used to approximate inflow profiles by algebraic polynomials or Gaussian functions are observed to introduce numerical artifacts that significantly affect the flow and therefore its stability. The multi-stage scale-matching fitting approach developed in this study is designed as a robust successive-order approximation of the inflow conditions. Our objective is to demonstrate its robust capability of taking into account the main physical features of the inlet velocity profiles, which, in turn, allows us to significantly improve the prediction of the flow instability occurring in the pump diffuser. Firstly, the RANS and URANS simulations of the entire machine are carried out by OpenFOAM using the k−ω SST turbulence model. The simulation results show that the RANS simulation is efficient in correctly capturing the diffuser inlet velocity profile except for developed stall conditions. The RANS simulations are carried out for cases with three different kinds of leakage configurations between the impeller and the diffuser. For each case, five flow rates were simulated to get the basic data for fitting the inlet profiles for a total of 125 simulations. The diffuser inlet velocity profiles are averaged in the azimuthal direction and fitted such to obtain an explicit function for the azimuthally-averaged velocity profile that varies with the flow rate Q. The fitting results are very close to the original data, and using our fits to predict the diffuser flow instabilities we show that our modeling approach compares well against the URANS simulations of the whole machine.

Validation of numerical simulations for investigating flow control in hypersonic inlets

Various flow control devices have been conceived for hypersonic inlets to suppress the inlet unstart and reduce the total pressure loss over the wide range of operating conditions of hypersonic systems. In particular, bleed systems that remove the low-momentum portion of the flow have drawn attention because they effectively reduce shock-induced flow separation and suppress inlet unstart. Numerical simulations are crucial for investigating the effectiveness of different bleed configurations in hypersonic inlets during the design phase. However, the flow structure in these inlets and the effect of the bleed on the flow are challenging to predict due to complicated factors such as shock-wave/boundary-layer interactions and compressibility effects. Moreover, since the boundary conditions, turbulence model, and turbulence corrections affect the numerical results, the most appropriate model can be difficult to determine. Therefore, a numerical solver was developed and evaluated on a series of validation cases with available experimental data to establish the fidelity of the numerical simulations. Seven validation cases, ranging from an elementary configuration involving a flat plate to a complex configuration involving a flat plate with a porous bleed and plenum chamber, were investigated. The flat plate flow numerical results, including the turbulent boundary layer and shock-wave/laminar boundary-layer interactions, were consistent with previous experimental and numerical results. However, in the hypersonic inlet cases, the actual physical phenomena could not be represented without considering compressibility and streamline curvature effects, which depend on the hypersonic inlet configuration. Thus, the effects of turbulence corrections on the numerical results of various hypersonic inlet configurations were examined. For cases with rapid expansion near the inlet throat or inlets with curved walls, compressibility or rotation/curvature corrections were necessary to accurately capture the size of the recirculation zone and reproduce the wall pressure data and shock structure along the flow path. However, for bleed flows on flat plates, the simulations were accurate without applying turbulence corrections. Thus, these turbulence corrections should be applied only when rapid expansion occurs or the wall near the shock-induced separation zone is curved. This paper provides the best practice appropriate for various supersonic, hypersonic flow cases, and can be utilized in future numerical studies on hypersonic inlet boundary layer control.

Application of immersed boundary method to the simulation of three-dimensional flow in solid rocket motors

The immersed boundary method (IBM) is currently utilized in the simulation of two-dimensional axisymmetric flow in solid rocket motors. In this paper, the IBM is applied to three-dimensional flow fields, keeping the grain surface fixed. Based on the Cartesian grid, a three-dimensional Euler flow solver is developed using the finite difference method. All boundaries of the flow field are processed using the IBM, including the slip walls, mass flow inlet, pressure outlet, and rotational periodic boundary. Specific implementation of these boundary conditions and the mesh generation process are described. Using the ray-casting approach and the alternating digital tree data structure, an efficient method is proposed to determine the intersection relationship between a rectangular volume grid cell and a triangular surface mesh element. The numerical results of Taylor–Culick flow verify that the developed solver has more than one-order accuracy in space. To conduct the validation of the established method, three typical grains are selected for flow simulations, namely, the perforated cylindrical grain with burning on both the ends and the inner surface, the end-slotted end-burning grain, and the finocyl grain, respectively. The simulated results are compared with those of the zero-dimensional interior ballistics, the two-dimensional axisymmetric IBM, and the body-fitted grid method, verifying the fidelity of the developed three-dimensional flow solver.

Transient Analysis of Fluid Flow through a Closing Blowout Preventer Using Coupled Domain Computational Fluid Dynamics

Summary Erosion and forces on rams may prevent a blowout preventer (BOP) from sealing a well. Analyzing the flow field throughout a BOP may provide insight into these flowing effects on the inability of a BOP to seal the well. 3D transient simulation of fluid flow throughout closing BOP fluid domains is demonstrated using computational fluid dynamics (CFD). Simulation may be used to analyze the transient stress, pressure, and velocity fields throughout a BOP domain as it is closing. Many challenges exist in simulating a closing BOP using CFD, including boundary conditions and treatment of dynamic meshing. Solutions to those challenges are presented in this work. CFD simulations are carried out using ANSYS Fluent v19.2 (ANSYS, Canonsburg, Pennsylvania, USA). For inlet boundary conditions to the CFD domain, the CFD simulations are explicitly coupled with a 1D wellbore simulator. The 1D wellbore simulator provides a connection between the BOP and constant pressure reservoir. Numerical instability is present during this coupling process. An implementation for dealing with this instability is presented. An example validation case is presented to demonstrate the accuracy of CFD for pressure fields throughout valves. A second 2D axisymmetric case is shown to demonstrate the meshing and coupling simulation process. A third case, simulation through a 3D shear geometry is then presented to show the applicability of the process to a more complex geometric design. Velocity and stress fields are plotted to show the practicality of CFD in analyzing the probable causes of failure in BOP closures.

Study on the Selection of Single-Screw Steam Compressors in Industrial Steam Supply

Both direct and indirect heating compression methods were proposed to satisfy the requirement of industrial steam compression and supply. The compression process in a single-screw compressor was analyzed with the determination of different inlet and outlet boundary conditions. Considering the misalignment of meshing pairs caused by the offset of the star wheel axis and screw origin, the differential expansion of the vertical meshing pair was further analyzed. The inner ring of the sealing end face, the wall of the inner ring of the bearing at the inlet and outlet ends, and the bottom surface of the bracket were analyzed by different coordinate systems and different constraints, thus facilitating the design and selection of the single screw. The critical point for the design of a steam-type single-screw compressor is an outlet temperature of 350 °C and an outlet volume flow rate of 130 m3/min. At a flow rate of 130 m3/min, when the temperature exceeds 350 °C, the reliability of the compressor is still limited, and the differential expansion of the meshing pair exceeds 0.3 mm. In addition, superheating of steam can be improved by applying a centrifugal compressor with cascade compression and centrifugal compression in conjunction with reflux adjustment at the compression outlet.

Study on boundary reflection mechanism of continuous wave mud pulse in the flow loop

Continuous wave (CW) mud pulse is one of the essential ways of high speed data transmission while drilling. The boundary reflection process and mechanism need to be clarified, which seriously affects the analog interpretation of pressure waves in flow loops and drilling conditions. In this paper, the boundary reflection of mass inlet and pressure outlet is studied by using traditional acoustic theory and numerical simulation methods, and mutual verification is carried out with flow loop. The results show that the pressure wave generated by the CW generator can be divided into compression wave and expansion wave and transmitted to the upstream and downstream pipelines. The inlet boundary reflection is the hard boundary reflection in acoustics. The phase of reflected wave is the same as that of the incident wave. The outlet boundary is the soft boundary, the reflected wave phase is 180° opposite to the incident wave. In particular, the process and mechanism of secondary reflection of stator and rotor structure on pressure wave are analyzed for the first time, which provides a theoretical basis for pressure wave amplitude. Finally, due to the possibility of cavitation phenomenon in the flow loop, it is different from the pressure environment of the bottom under drilling conditions and should to study further.

Hemodynamic simulation in the aortic arch with the lattice Boltzmann method

Aortic diseases have high mortality rates, wherein wall shear stress (WSS) and oscillatory shear index play important roles. Previous studies focused on describing the WSS distribution; however, no report has investigated how hemodynamic parameters determine the distribution of WSS. This study investigates the parameters affecting the WSS distribution and determines the variations of these parameters. A realistic healthy aortic geometry is reconstructed from computed tomography medical images, and a flow simulation is performed using the lattice Boltzmann method. The inlet velocity waveform from the Doppler ultrasound measurement is imposed as the inlet boundary condition, whereas the three-element Windkessel model is used as the outlet boundary condition. The measured outlet flow rate waveforms are used to validate the simulation. A good agreement is found between the outlet flow rate waveform obtained from the measurement and that from the simulation: the descending artery, innominate artery, left common carotid, and left subclavian artery receive 63.42%, 24.01%, 4.14%, and 8.46%, respectively, of the total inlet flow rate over the cardiac cycle in the measurements and 62.17%, 24.61%, 4.7%, and 8.44%, respectively, in the simulation. The simulation shows that the temporal and spatial distributions of the WSS are separately determined by the flow rate and impacting angle. The flow rate ratio between the inlet and outlet decreases with an increase in Re. This relation can be fitted well by the exponential function. Moreover, the impacting angle between the blood flow and the vessel centerline is determined by the vessel geometry only.

Numerical and boundary condition effects on the prediction of detonation engine behavior using detailed numerical simulations

High-fidelity numerical simulations of an experimental rotating detonation engine with discrete fuel/air injection were conducted. A series of configurations with different feed-plenum pressures but with constant equivalence ratio were studied. Detailed chemical kinetics for the hydrogen/air system is used. A resolution study for the full rotating detonation engine (RDE) system simulation is also conducted. Two kinds of boundary conditions, a total pressure boundary and a constant mass flow rate boundary, are used to assess the effects of the inlet boundary. As mass flow rate is increased, the total pressure boundary causes more error in the axial pressure distribution while the constant mass flow rate gives a better solution for all cases ran. The simulations confirm experimental findings, and reproduce qualitative as well as some of the quantitative trends. These results demonstrate that a) fuel-air mixing is highly non-uniform within the detonation chamber, leading to variations in local equivalence ratio, b) the fuel and oxidizer injectors experience significant backflow as the detonation wave passes over, but recover at different rates which further augments the inefficiencies in mixing, and c) parasitic combustion in the mixing region makes the detonation wave weak by extending the reaction zone across the wave.

Domain reduction strategy for large-eddy simulation to predict underwater radiated noise from a marine propeller

A systematic domain reduction strategy is proposed to mitigate the high computational cost of performing a large-eddy simulation (LES) for predicting underwater radiated noise from a marine propeller. The key concept of this strategy is to determine where detailed analysis is necessary beforehand and accordingly reduce the computational domain. The strategy comprises the following steps: (1) performing a Reynolds-averaged Navier–Stokes (RANS) simulation in the full domain, including the entire hull; (2) quantitatively analyzing the region affected by the propeller; (3) reducing the domain to encompass most of the propeller’s effect; and (4) conducting an LES in the reduced domain, using the flow field from the RANS simulation as an inlet boundary condition. By implementing the proposed strategy, the LES domain length is reduced by up to twice the propeller diameter in the upstream direction from the propeller, representing only 7% of the hull’s total length. The strategy’s effectiveness is validated by comparing the simulation results with the experimental data obtained at the Korea Research Institute of Ships and Ocean.

Inclined dense discharge in stagnant and wave environments: An experimental and numerical study

Coastal desalination plants have increased in number and size over the past decades due to the water crisis in the world. During the process of desalination, in addition to fresh water, brine with higher salinity than seawater is also produced that is commonly discharged back into the sea through the marine outfalls. This study aimed to numerically investigate the mixing and geometrical characteristics of 60° inclined dense jet in stagnant and wave environments. The wave environment is assumed to be a more realistic condition for marine discharges. Therefore, a new solver using AGFoam, which is a part of the ESI-OpenCFD package of OpenFOAM, was developed. New formulations were deployed for the estimation of k and ω at the inlet and outlet boundaries of the wave environment. The results were compared to the behavior of dense jets in the stagnant water. The comparisons demonstrated that wave motions lead to the oscillation of dense jet near the source and this oscillation in turn increases flow mixing and dilution up to the impact point. So it observed that in wave motions, pollutants spread faster and it changes flow width and geometry significantly.

CFD study of two-phase cross flow and heat transfer in sub-channels of pressurized water reactor fuel assemblies

The safety of nuclear power systems is extremely important. The development of nuclear power is predicated on the safety of the system. Under certain operating conditions, the coolant flowing through the fuel assembly will undergo phase change, resulting in gas-liquid two-phase flow. The existence of the two-phase flow will change the stability of the coolant flow and thus affect the reliability of the core instrumentation under accident conditions. The presence of the two-phase flow will also change the heat transfer coefficient of the coolant, thus affecting the temperature distribution on the surface of the instrument guide tube. This paper adopts the computational fluid dynamics method. On the one hand, this paper calculates the two-phase cross flow of the two-channel. By changing the inlet boundary conditions to achieve the elimination of diversion cross flow, the two-phase cross flow phenomenon was observed, which laid the foundation for future experiments. On the other hand, calculations of the surface temperature of the instrument guide tube. The surrounding flow field show that the temperature of the surface of the instrument guide tube is higher in two phases than in one phase. The gas phase moves to the surface of the instrument guide tube.

Influences of the cavity leakage flow on shrouded stator performance at different inlet boundary layer shapes

By using the validated numerical method to simulate the annular shrouded stator with the inter-stage seal cavity, the stator aerodynamic performance related to the cavity leakage flow was examined. The current study also indicated the interactions between the leakage flow and the mainstream. Discussions on the developments of secondary flow movement and hub corner separation were conducted, and the performances at different incoming boundary layer shapes were assessed using both the total pressure loss coefficient and the entropy-based loss coefficient. The results indicate that the cavity leakage flow creates a new vortex close to the leading edge of blade and is crucial to the passage vortex development and the concentrated shedding vortex size. At the same time, the cavity leakage flow weakens the transverse deflection of flow near the end wall and strengthens the three-dimensional flow effect. The two loss coefficients for the shrouded stator with seal cavity change little by thickening the boundary layer. The proper boundary layer skew as well as the interacted cavity leakage flow have stronger resistance to the deflection of the passage vortex and the transverse pressure gradient.

Pulsating pressurization of two-phase fluid in a pipe filled with water and a little gas

Although two-phase flows containing gas and water have received extensive attention, the pulsating pressurization effect of a two-phase fluid in a pipe is unclear and the influence of the gas-phase content has not been revealed. This paper discusses the pulsating pressurization of such a two-phase fluid. First, the two-phase Navier–Stokes equations are derived and an algorithm is developed based on MacCormack's method. The reliability of the algorithm is examined and validated using Poiseuille's theory and existing experimental two-phase flow data. Finally, the influence of several key factors is discussed, including the gas-phase fraction and pipe slenderness. Our results show that a significant pulsating supercharging phenomenon occurs when the gas-phase fraction is less than 10−3. When the gas-phase fraction is greater than this critical value, the pulsating supercharging effect decreases significantly with the increasing gas-phase fraction. The equivalent elastic modulus of the two-phase fluid rapidly decreases as the gas-phase fraction increases, and the pressure disturbance is absorbed by the gas bubbles, causing an apparent weakening of the pulsating supercharging effect. Thus, decreasing the gas-phase content can enhance the pulsating supercharging effect. The pipe slenderness has a very limited influence on the pulsating pressurization process, and the maximum reduction is only 7.3% for slenderness ratios of up to 2000. Moreover, we derive and propose a new mathematical expression for the inlet boundary that is applicable to gas–liquid two-phase flows. To our knowledge, this paper extends the pulsating pressurization range from the single-phase to two-phase fluid for the first time and reports different physical phenomena and regularity. The present research clarifies the pulsating pressurization phenomenon in two-phase flows, providing a valuable reference for pulsating pressurization design.

Numerical Study of Reducer Modification with Adjuster Opening Variations on Turbine Lube Oil Pipe

The success criteria of the power plant are represented by EAF (Equivalent Availability Factor) value. In 2021, one of the causes of the Forced Outage (FO) at Adipala Steam Power Plant was the failure of the main lube oil turbine pipe. The sudden contraction of the reducer resulted in the previous failure. Modifications were made to the reducer using a conical shape to reduce the number of welding processes and minimize the probability of failure. Therefore, a study on reducer modification needs to be carried out to study the impact of changing the shape of the reducer and changing the opening check valve on process parameters and flow in the main lube oil turbine pipe. The modification of the reducer was the main focus in this study. This research aims to analyze the pressure of turbine lube oil in the existing adjuster and the modified adjuster, using the Computational Fluid Dynamics technique with check valve adjuster variations (distance between the tip of the check valve and the inner wall of the reducer). The inlet boundary condition was defined by a pressure inlet of 285803.4 Pa. Outlet boundary condition was set by a mass flow of 65.72 kg/s. The curve surface was set as wall boundary conditions with a stationary wall, no-slip, and standard roughness model. The oil pressure in the modified adjuster increased compared to the oil pressure in the existing adjuster. The pressure on the oil flow was required to distribute oil to the turbine bearings. With the small increase in pressure after the modification, the turbine lube oil transfer improved. The pressure drop (Δ P ) value that occurred in the conical-shaped modified adjuster was smaller than the pressure drop (Δ P ) in the existing adjuster. This is because the resistance on the modified adjuster was less than the existing adjuster. The flow streamlines that formed backflow and vortex on the conical modified adjuster were less compared to the existing adjuster due to fewer obstacles in the conical modified adjuster.

Workflow Comparison for Combined 4D MRI/CFD Patient-Specific Cardiovascular Flow Simulations of the Thoracic Aorta

AbstractComputational fluid dynamics (CFD) has been widely used to predict and understand cardiovascular flows. However, the accuracy of CFD predictions depends on faithful reconstruction of patient vascular anatomy and accurate patient-specific inlet and outlet boundary conditions. 4-Dimensional magnetic resonance imaging (4D MRI) can provide patient-specific data to obtain the required geometry and time-dependent flow boundary conditions for CFD simulations, and can further be used to validate CFD predictions. This work presents a framework to combine both spatiotemporal 4D MRI data and patient monitoring data with CFD simulation workflows. To assist practitioners, all aspects of the modeling workflow, from geometry reconstruction to results postprocessing, are illustrated and compared using three software packages (ansys, comsol, SimVascular) to predict hemodynamics in the thoracic aorta. A sensitivity analysis with respect to inlet boundary condition is presented. Results highlight the importance of 4D MRI data for improving the accuracy of flow predictions on the ascending aorta and the aortic arch. In contrast, simulation results for the descending aorta are less sensitive to the patient-specific inlet boundary conditions.