장근식 교수

Repeated derecruitments exacerbated lung injury, particularly at the bronchiolar level in the dependent portion. Strategies to minimize this type of injury should be incorporated when designing optimal ventilator strategies in acute respiratory distress syndrome patients.

Abstract Interactive vortex shedding in the multiply connected domain formed by a pair of circular cylinders is analysed by the FEM–FDM blending technique. The vorticity–streamfunction formulation is used to solve the incompressible Navier–Stokes equations at Re = 100, with the time‐dependent wall streamfunctions determined from the pressure constraint condition and the far‐field streamfunctions from the integral series formula developed earlier by the authors. The standard Galerkin finite eleme

The chemical process of CN formation in a CO-N 2 mixture is studied through temporally resolved intensity measurement of CN violet radiation occurring in the reflected-shock region of a shock tube. A 78% CO-22% N 2 mixture is driven by cold hydrogen to a shock speed of up to 3.45 km/s, to produce a reflected-shock temperature corresponding to Martian entry flight of up to 6.4 km/s. Absolute calibration of spectrometer is performed using a standard lamp of radiance. A reaction model is constructe

Abstract The unsteady incompressible Navier‐Stokes equations have been accurately solved for the laminar flow past a circular cylinder in the Reynolds number range 50–200. A direct elliptic solver called the SEVP is used to rapidly advance the streamfunction in time, facilitating the overall convergence to the fully periodic or quasi‐steady state. A new integral‐series method is developed for the far‐field streamfunction condition on a finite two‐dimensional computational domain. The use of four

Interactive natural convection heat transfer from a pair of vertically separated horizontal circular cylinders of equal diameter was studied by solving the Navier-Stokes and the energy equations numerically. The flow was assumed to be laminar, and each cylinder was kept isothermal. To handle the present complex flow domain, zone-dependent grid systems were successfully employed with grid overlapping in between. Results are presented for Pr = 0.7 and 104 ≤ Ra ≤ 105, where the Rayleigh number is b

ABSTRACT A compressible two-fluid two-phase flow model based on two sets of governing equations is formulated. We solve, using the second-order Harten, Lax, and van Leer (HLL) scheme, five disparate two-phase benchmark problems such as shock propagation in the two-phase medium, the cavitating flow, and the gravity-induced phase separation. In the conventional HLL scheme, the simple sonic speeds evaluated from the two single phases are used in lieu of the fastest speeds in the two phases, since t

Vortex shedding from an oscillating circular cylinder was numerically investigated at Re = 100 with the Navier-Stokes equations and the new boundary conditions. The detailed shedding patterns are characterized by means of streakline plotting and lift-coefficient curves. A parameter map is presented which distinguishes the synchronized shedding from the asynchronous and the double vortices shedding from the single vortex shedding. The computational result is in good agreement with earlier experim