Numerical modelling of industrial processes is a tool of great importance as it makes development of efficient engineering solutions more economical and faster. One of currently fast developing fields is additive manufacturing, which is based on process of direct laser deposition (DLD) of metal powder. In order to derive a model of DLD process, in this work, existing finite volume Eulerian model of laser welding and cutting (main model) is extended with Lagrangian particle tracking model, which simulates depositing powder and its melting by discrete element method (melting powder model). Clad formation is achieved through mass transfer from melting powder model to main model. Both models are also coupled in enthalpy and momentum yielding mass, enthalpy and momentum balance. A test case which demonstrates conservation of mass, enthalpy and momentum is presented. Finally an application of derived model to DLD process modelling is shown.