Overview This study uses ANSYS Fluent software to simulate blood flow through an occluded artery via computational fluid dynamics (CFD) analysis. The model features a bifurcated blood vessel with stenosis (narrowing) at its center. Blood properties are defined with a density of 1060 kg/m³ and dynamic viscosity of 0.35 kg/m·s. The stenotic region is mathematically defined using a curved function. The primary objective is to analyze blood flow behavior through the narrowed section. Blood enters through two inlet branches at a combined mass flow rate of 0.002385 kg/s, while vessel walls are treated as rigid boundaries. The model geometry was created using ANSYS Design Modeler and discretized with ANSYS Meshing, employing a structured mesh containing 85,222 elements. Methodology The vessel stenosis geometry was generated using a parametric curve function defined by the equation: y = 0.0002475cos(πx/0.001), which describes the coordinate points forming the narrowed profile. As an illustration, a 30% stenosis indicates that the constricted diameter is 70% of the normal vessel diameter. To evaluate fluid behavior under varying conditions, the stenosis severity was systematically varied across seven cases: 30%, 40%, 50%, 60%, 70%, 80%, and 90% occlusion. Key Findings Post-processing revealed 2D distributions of pressure and velocity, along with pathline and vector visualizations. Velocity contours demonstrate peak values precisely at the stenotic throat, where the flow cross-sectional area reaches its minimum. Pressure distributions show a decline in fluid pressure downstream of the stenosis, with values dropping below the inlet branch pressures. Graphical analysis of pressure, velocity, and pressure differential versus stenosis severity reveals that increasing occlusion percentage correlates with greater pressure losses and elevated blood velocities through the constricted zone, directly attributable to the enhanced flow obstruction.

# Blood Flow in Occluded Artery - Project Overview This study employs ANSYS Fluent software to simulate hemodynamics in a stenosed artery through CFD analysis. The model incorporates a horizontal vessel featuring a curved obstruction at its midpoint along the flow pathway. Blood is characterized by a density of 1035 kg/m³ and viscosity of 0.0043 Pa·s.  The vessel geometry is constructed using a curved profile based on a Gaussian distribution function, which mathematically describes the radial variation along the vessel's longitudinal axis. The function is dependent on the axial coordinate (z), with a stenosis severity (st) of 0.90 (representing 90% occlusion) and a geometric slope parameter (σ) of 0.85 defining the constriction gradient. Blood enters at a mass flow rate of 0.013662 kg/s.  The primary research objective is to quantify the pressure differential generated along the flow path due to arterial stenosis. # Geometric Design & Computational Grid The three-dimensional geometry was developed in ANSYS Design Modeler. The configuration consists of a cylindrical vessel with mid-section stenosis. The constricted profile was generated by revolving a parametric curve around the vessel's centerline axis. This curve was defined by importing a coordinate dataset containing discrete spatial points. The vessel measures 0.18 m in length with a nominal diameter of 0.004 m. Mesh generation was performed in ANSYS Meshing utilizing a structured grid topology comprising 431,156 computational cells. The accompanying figure illustrates the mesh configuration. # Computational Setup The simulation incorporates the following assumptions: - Pressure-based solution algorithm- Steady-state flow conditions- Gravitational effects neglected **Summary of Simulation Parameters:** | **Category** | **Parameter** | **Setting** ||--------------|---------------|-------------|| **Flow Model** | Viscous treatment | Laminar || **Inlet Boundary** | Type | Mass flow inlet || | Mass flow rate | 0.013662 kg/s || **Outlet Boundary** | Type | Pressure outlet || | Gauge pressure | 0 Pa || **Wall Boundary** | Motion | Stationary/no-slip || **Solution Method** | Coupling scheme | SIMPLE || | Pressure discretization | Second-order || | Momentum discretization | Second-order upwind || **Initialization** | Method | Standard || | Gauge pressure | 0 Pa || | Axial velocity | 1.054351 m/s | # Findings Post-processing yielded two- and three-dimensional contour visualizations of pressure, velocity, and pressure gradient distributions. Additionally, a plot depicting static pressure variation along the vessel centerline was generated using normalized axial distance coordinates. Analysis reveals that the maximum pressure drop occurs within and immediately downstream of the stenotic region, demonstrating the hemodynamic impact of arterial occlusion.

Project Overview This project presents an ANSYS Fluent simulation of time-dependent pulsatile blood flow through a simplified arterial bifurcation model. Geometry and Meshing The fluid domain was created in Design Modeler, with mesh generation performed in ANSYS Meshing. An unstructured mesh containing 168,367 elements was employed for the computational domain. Boundary Conditions Blood mass flow rates are specified as 0.001570178 kg/s at the inlet and 0.00078576 kg/s at each outlet. Inlet blood pressure is set at 250 Pa (approximately 1.87515 mmHg). For reference, physiological blood pressure in major human arteries typically ranges between 80 and 120 mmHg. Pulsatile Flow Implementation The pulsatile characteristics of blood flow are captured through a User-Defined Function (UDF), which modulates inlet velocity as a sinusoidal function of time, replicating the cardiac cycle’s rhythmic nature. Results and Clinical Insights The transient solver provides time-resolved flow data, with results presented at t = 0.162s, corresponding to peak systolic velocity. The simulation yields clinically relevant insights into arterial pathology susceptibility. High-Pressure Risk Zones: Pressure contour analysis at t = 0.16s reveals critical stress concentrations at the bifurcation apex, where flow streams diverge. Blood pressure reaches 125 Pa at this location—approximately half the inlet pressure—identifying this region as vulnerable to arterial wall rupture. Stenosis-Prone Regions: Wall Shear Stress (WSS) distribution analysis identifies areas susceptible to stenosis formation. Consistent with medical literature establishing low WSS as a stenosis predictor, the bifurcation apex exhibits minimal shear stress values, indicating heightened risk for atherosclerotic plaque development and subsequent arterial narrowing.

Description This project uses ANSYS Fluent to simulate how coronavirus-laden droplets released during speech can travel at sub–social-distance separations. We conduct and analyze the CFD study to assess transmission risk while talking. The scenario models exhaled particles from an infected speaker and their transport toward another person within a defined indoor volume. Geometry is built in DesignModeler as a 3D domain measuring 1.6 m × 2 m × 2.6 m, with two individuals facing each other 0.8 m apart. The infected person’s mouth serves as the particle source. Meshing is performed in ANSYS Meshing, producing 724,076 elements. Because dispersion evolves over time, a transient solver is employed. Talking Methodology To capture particle transport and deposition, the discrete phase model (DPM) is used, treating droplets as a dispersed phase moving through a continuous air field. Unsteady particle tracking is enabled with a 0.001 s time step. An injection is defined at the mouth surface with inert particles of 1×10⁻⁶ m diameter and 310 K temperature, released from 0 to 20 s. A custom profile prescribes the particle velocity and mass flow rate during speech, with a sinusoidal velocity history peaking at 0.33 m/s and the mass flow rate tied proportionally to that velocity. Turbulence is modeled with RNG k–ε, and the energy equation is solved to capture temperature effects. Talking Conclusion Post-processing provides particle tracks at multiple times, reported by residence time and instantaneous velocity. The results show particle emission occurs during the first 20 s; during the subsequent 20 s, only previously emitted particles continue to move within the gap between the individuals. Overall, the simulation indicates that speaking for 20 s without a mask can lead to particles reaching the other person by about 40 s, potentially exposing them to the virus.

Description This project uses ANSYS Fluent to simulate speech-driven release of coronavirus particles from an infected person and assess how face shields (or masks) block transmission to another individual. The 3D geometry is built in DesignModeler as a 1.6 m × 2 m × 2.6 m domain with two people facing each other at an 80 cm separation. The patient’s mouth is modeled as the emission source. Meshing is done in ANSYS Meshing (724,076 elements), and a transient solver is used to capture time-dependent particle dispersion. Methodology To study short-range propagation, the discrete phase model (DPM) is employed, treating expelled droplets as a discrete phase within a continuous airflow field. Unsteady particle tracking is enabled with a 0.001 s time step. An injection at the mouth surface releases inert particles (diameter 1×10⁻⁶ m, temperature 310 K) from 0 to 20 s. A custom profile prescribes the particle exit velocity and mass flow rate during speech: the velocity follows a sinusoid peaking at 0.33 m/s, with flow rate proportional to velocity. DPM boundary conditions assign Escape at the mouth (particles exit through this boundary) and Trap on the patient’s shield/mask surfaces (particles are captured and accumulate there). Turbulence is modeled using RNG k–ε, and the energy equation is solved to obtain the temperature field. Conclusion Post-processing yields particle tracks classified by residence time and velocity. Consistent with the setup, particles are emitted periodically over the first 20 s. The shield causes expelled particles to deposit on its surface, preventing their forward transmission to the nearby person.

Description This project simulates the delivery of an asthma spray into human lungs using ANSYS Fluent. The 3D geometry—built in SpaceClaim—represents a simplified lung model with a 50 cm inlet diameter. The mesh (ANSYS Meshing) contains 3,734,238 elements. Given the time-dependent nature of inhalation and particle motion, a transient solver is used. Asthma Spray Methodology A one-way coupled Discrete Phase Model (DPM) tracks aerosol particles moving through a continuous air phase. Air enters at 5 m/s, with gravity set to −9.81 m/s² along the z-axis. Particles (diameter 100 µm) are introduced via a surface-velocity injection at the inlet. Turbulence is resolved with the realizable k–ε model. Particle trajectories inside the lung domain are computed and visualized to assess transport and deposition behavior. Conclusion Post-processing provides 2D and 3D contours of velocity and pressure, along with an animation of particle tracks throughout the lungs, illustrating the spray’s distribution following inhalation.