Lagrangian marker particles

Marker and Cell (MAC) Method The first method capable of modeling gas-hquid flows, separated by a moving interface, was the MAC of Harlow and Welch [4]. In the MAC method, as shown in Fig. 2b, the massless markers are used to define the location and track the movement of fi ee surface. This is in fact a combination of a Eulerian solution of the basic flow field, with Lagrangian tracking of marker particles. The computational cycle in the MAC method consists of the advancement of discrete field variables fi om an initial time to to the subsequent time to + At by accomplishing the steps below. 

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