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Try to keep track of your cache files. The best way is to create a common folder where the Cinema 4D files are stored together with the simulation files. This also concerns naming (see above). The cache folder can be adjusted under the “Scene” tree's “Cache” tab.
RealFlow | Cinema 4D writes one particle file per "Fluid" container and frame, and one mesh file per "Mesher" container and frame. Both, the number and size of the files can grow quickly, so please make sure that you have enough free disk space available.
Simulation data are not saved with the Cinema 4D project file. If you close a file without caching all previously simulated data will be lost. The scene elements (emitters, daemons, etc.) will be kept, of course.
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