Numerical prediction of the distribution of black carbon in a street canyon using a semi-Lagrangian finite element formulation

Abstract

We present a procedure for coupling the

uid and transport equations to model the distribution

of a pollutant in a street canyon, in this case, black carbon (BC). The 

uid 

ow

is calculated with a stabilized �nite element method using the Quasi-Static Variational

Multiscale (QS-VMS) technique. For the temperature and pollutant transport we use a

semi-Lagrangian procedure, based on the Particle Finite Element Method (PFEM) combined

with an Eulerian method based on a Finite Increment Calculus (FIC) formulation.

Both methods are implemented on the open-source KRATOS Multiphysics platform. The

coupled numerical formulation is applied to the prediction of the transport of BC in a

street canyon, which can be a useful tool to lessen the impact of pollutants on pedestrians.

Two test cases have been studied: a 2D simpli�ed case and a more complex 3D one.

The main goal of this study is to propose a useful tool to study the e�ect of pollution on

pedestrians in a street-level scale. Good comparison with experimental results is obtained.

Keywords: convective transport, convection{di�usion{reaction, transient, �nite element

method, FIC, PFEM, Eulerian, Lagrangian.