Three independent methods were used to evaluate transpiration of a boreal forest: the branch bag, sap flow and eddy covariance methods. The branch bag method encloses several thousand needles and gives a continuous record of branch transpiration. The sap flow method provides a continuous record of sap velocity and an estimate of tree transpiration. The eddy covariance method typically measures ...

A pressure-based implicit procedure to solve the Euler and Navier-Stokes equations on a nonorthogonal mesh with collocated finite volume formulation is described. The boundedness criteria for this procedure are determined from Normalized Variable diagram (NVD) scheme.The procedure incorporates the ε−k eddy-viscosity turbulence model. The algorithm is tested for inviscid and turbulent transonic ...

A tidal bore is a positive surge propagating upstream as the tidal flow turns to rising in river mouths exhibiting a converging funnelled channel forms during low freshwater conditions. While some recent laboratory experiments brought new insights to the turbulent motion generated by tidal bores, a numerical model based upon the Navier-Stokes equations is proposed to investigate the complicated...

A High Temperature Gas-cooled Reactor (HTGR) is one of the renewed reactor designs to play a role in nuclear power generation. This reactor design concept is currently under consideration and development worldwide. The combination of coated particle fuel, inert helium gas as coolant and graphite moderated reactor makes possible to operate at high temperature yielding a high efficiency. In this ...

Compressible large-eddy simulations of turbulent flow over a wall-mounted hump with active flow control are performedand comparedwithprevious experiments. Theflow is characterizedby the unsteady separationbefore the steep trailing edge, which naturally reattaches downstream of the hump to form an unsteady turbulent separation bubble. The lowMachnumber large-eddy simulation demonstrated a goodpr...

The aerodynamic noise radiation from a side view mirror (SVM) in the high-speed airflow is calculated by the combination of unsteady incompressible fluid flow analysis and acoustic analysis. The transient flow past the generic SVM is simulated with variable turbulence model, namely DES Detached Eddy Simulation and LES (Large Eddy Simulation). Detailed velocity vectors and contour plots of the t...

Simulations of stochastically forced shear-flow turbulence in a shearing-periodic domain are used to study the spontaneous generation of large-scale flow patterns in the direction perpendicular to the plane of the shear. Based on an analysis of the resulting large-scale velocity correlations it is argued that the mechanism behind this phenomenon could be the mean-vorticity dynamo effect pioneer...

We evaluate the applicability of a production computational fluid dynamics code for conducting detached eddy simulation for unsteady flows. A second-order accurate Navier-Stokes code developed at NASA Langley Research Center, known as TLNS3D, is used for these simulations. We focus our attention on high Reynolds number flow (Re = 5× 10 − 1.4× 10) past a circular cylinder to simulate flows with ...

The flow and turbulence in an IC engine cylinder were studied using the SSG variant of the Reynolds stress turbulence closure model. In-cylinder turbulence is characterized by strong turbulence anisotropy and flow rotation, which aid in air-fuel mixing. It is argued that solving the differential transport equations for each turbulent stress tensor component, as implied by second-moment closures...