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Application of double-barreled cannon stent grafts aortic repair (DoBAR) was reported in 2011 for extremely large aortic aneurysms of patients when there was no proper size of grafts for the emergent treatment. Fixation characteristics of the double stent grafts are obtained in a laboratory setting, and are incorporated with those of single Zenith TX2 grafts of sizes from 34 to 42[Formula: see text]mm. Radial stress and shear increase linearly with the oversizing parameter but decrease with increasing stent diameter. The slope of the linear relationship is practically the same for this group of grafts. When the original circular stent grafts of diameter 36 and 38[Formula: see text]mm are deformed to form DoBAR of diameter 44 or 46.4[Formula: see text]mm, the formation could provide higher radial stress and shear to secure fixation for endo-aortic repair. The experimental results of single and DoBAR grafts can be incorporated for clinical application of DoBAR for emergent treatment.

This study extracted hemodynamic information from echocardiogram to complement the left ventricle ejection fraction and the stroke volume for cardiac evaluation and diagnosis. The dynamic characteristics of irregular wall motions can be analyzed by kinetic energy fluxes transferred from the left ventricle to the blood flow. A set of cardiac indices is developed for quantification and classification of echocardiogram for clinical application. The pumping characteristics can be further quantified through the work done by pressure and viscous stresses of the ventricle.

Blood flow in distensible arteries is nonlinear and time-dependent. The radial motion of the wall alters the dimension and geometry of the flow field. The nonlinear pulsating flow processes are successfully computed by mapping the wavy flow field to a fixed domain and by casting the geometric, kinematic and dynamic parameters of the flow into a dimensionless form of the Navier–Stokes equations. The complexity of the equations is compensated by a significant advantage in finite difference solutions. It is accomplished by using a fixed regular mesh network to model time-dependent irregular meshes in the physical domain for boundary layer development and vortices in pulsatile flows.

A two-phase thermo-hydrodynamic model is presented for transport in the vertical chamber of a porous media blood filtration device. A non-Darcy drag force formulation was employed. The Marble–Drew fluid–particle suspension model was used to simulate the plasma phase and the suspension (erythrocyte) particle phase. The non-dimensional transport equations were solved using a semi-computational procedure known as the homotopy analysis method (HAM). With the judicious use of the auxiliary parameter ℏ, HAM affords a powerful mechanism to adjust and control the convergence region of solution series. This method provides an efficient approximate analytical solution with high accuracy, minimal calculation and avoidance of physically unrealistic assumptions. Detailed computations are presented for the effects of Grashof number (Gr), momentum inverse Stokes number (Skm), Darcy number (Da), Forchheimer number (Fs), particle loading parameter (PL), buoyancy parameter (B) and temperature inverse Stokes number (SkT) on the dimensionless fluid phase velocity (U), dimensionless particle phase velocity (Up), dimensionless fluid phase temperature (Φ) and the dimensionless temperature of particle phase (Φp). A Prandtl number of 25 was used to simulate blood at room temperature. Excellent correlation was obtained between the HAM and numerical shooting quadrature solutions. The results indicated that there is a strong decrease in fluid phase velocities with increasing Darcian (first order) drag and second-order Forchheimer drag, and a weaker reduction in particle phase velocity field. Applications of the study include porous media bio-filtration devices and dialysis simulations.