A computer-implemented method for dynamically visualizing fluid velocity in a subsurface reservoir, which comprises: a) computing streamlines for the subsurface reservoir model, wherein the streamlines represent a streamline model; b) displaying a plurality of the streamlines in the streamline model, each streamline representing a fluid path in the subsurface reservoir; c) displaying a particle on each streamline at a simulation start time of the streamline model based on a fluid velocity for a respective streamline; d) removing the particle displayed on each streamline at the simulation start time or at another simulation time of the streamline model; e) displaying another particle on each streamline at another simulation time of the streamline model based on the fluid velocity for the respective streamline, wherein each another simulation time is a sum of a time step, wherein the time step is a predetermined time step or a default time step that represents equal increments between the simulation start time and a simulation end time used for modeling the plurality of streamlines in the streamline model and the time step is computed using the fluid velocity for each streamline and the number of pixels needed to display each streamline in order to achieve a continuous, uninterrupted, particle visualization between different simulation times of the streamline model that represents the actual fluid velocity or a proportionate fluid velocity for the streamline, each another simulation time is multiplied by a number of times step d) is performed, and the simulation start time of the streamline model; and f) repeating (108,204) steps d) and e) for each another simulation time of the streamline model that is less than the simulation end time of the streamline model using a computer processor, wherein each particle displayed on each streamline is no larger than a pixel needed to display the respective streamline. a) computing streamlines for the subsurface reservoir model, wherein the streamlines represent a streamline model; b) displaying a plurality of the streamlines in the streamline model, each streamline representing a fluid path in the subsurface reservoir; c) displaying a particle on each streamline at a simulation start time of the streamline model based on a fluid velocity for a respective streamline; d) removing the particle displayed on each streamline at the simulation start time or at another simulation time of the streamline model; e) displaying another particle on each streamline at another simulation time of the streamline model based on the fluid velocity for the respective streamline, wherein each another simulation time is a sum of a time step, wherein the time step is a predetermined time step or a default time step that represents equal increments between the simulation start time and a simulation end time used for modeling the plurality of streamlines in the streamline model and the time step is computed using the fluid velocity for each streamline and the number of pixels needed to display each streamline in order to achieve a continuous, uninterrupted, particle visualization between different simulation times of the streamline model that represents the actual fluid velocity or a proportionate fluid velocity for the streamline, each another simulation time is multiplied by a number of times step d) is performed, and the simulation start time of the streamline model; and f) repeating (108,204) steps d) and e) for each another simulation time of the streamline model that is less than the simulation end time of the streamline model using a computer processor, wherein each particle displayed on each streamline is no larger than a pixel needed to display the respective streamline.