9.1.1 Introduction

ANSYS FLUENT can solve the transport equation for an arbitrary, user-defined scalar (UDS) in the same way that it solves the transport equation for a scalar such as species mass fraction. Extra scalar transport equations may be needed in certain types of combustion applications or for example in plasma-enhanced surface reaction modeling . ANSYS FLUENT allows you to define additional scalar transport equations in your model in the User-Defined Scalars dialog box.