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According to a World Health Organization study done in 2016, cardiovascular disease is the largest cause of death globally. While strides in the clinical sector over the past few decades have greatly improved understanding of how cardiovascular disease is formed and affects the body, there are still unknowns such as the mechanics involved in disease progression. Computational fluid dynamics for blood flow has potential to greatly improve understanding of cardiovascular disease while offering advantages over traditional clinical methods that use imaging such as CAT scans. Such advantages include greater spatial resolution of the area of interest, non-invasive diagnostics, and the ability to simulate how treatment may affect a patient’s health. Software packages such as “SimVascular”, an open-source project, model hemodynamics by using the Navier-Stokes equations to govern blood flow. While robust, SimVascular cannot model additional blood flow processes such as blood clotting. In this study, an in-house solver is developed using a computing platform, FEniCS, with Python to model blood flow. LEoPart, a particle library, is used to model platelets as they are advected within the flow. Using a collision library, when platelets collide or exceed a specific wall shear stress magnitude, the particle’s color will change, visually indicating an "activation" stage for blood clotting. The velocity and wall shear stress from the simulation model were verified by calculating the absolute error when compared to the analytic solution for Poiseuille flow, 0.000826 m/s and 0.0015567 Pa respectively. From this baseline of modeling blood flow and platelets as particles in an easy-to-use and open-source format with Python and FEniCS, this code can continue to be modified by others to further examine and understand the mechanics involved with blood clotting, shear thinning, and more.&nbsp

A rolling road apparatus is a high-speed, treadmill-like device that is used in automotive wind tunnels to simulate near ground flows. Aerodynamic forces from models cause lifting forces on the rolling road belt which must be mitigated by suction systems, increasing sliding friction. Due to the combined effect of increased friction and the high-speed nature of these devices, thermal management of the belt sliding surface is of utmost importance. This work investigates how the known issues of temperature rise in these systems can be modelled and related to aerodynamic forces using simple analytical techniques. Further investigation is done into the design of a new style of heat exchanger for this type of device using analytical techniques. Detailed analysis is then done using the open-source computational fluid dynamics solver OpenFOAM to do conduction and conjugate heat transfer analysis of the heat exchanger design that was made using analytical methods. The thermal performance predicted by both methods are compared and recommendations are given to the applicability of each type of method in the analysis of this heat transfer problem.&nbsp