Oil mist separator and device for a crankcase ventilation

An oil mist separator of a device for crankcase ventilation of an internal combustion engine for separating oil particles from a gaseous fluid such as blow-by gas, the oil mist separator comprising:

• a nozzle plate arranged in a flow path of the gaseous fluid, the nozzle plate having a plurality of nozzle apertures extending through the nozzle plate, the nozzle apertures for the gaseous fluid to pass through the nozzle plate;
• a valve plate arranged at a downstream side of the nozzle plate, the valve plate configured to be movable in an opening direction relative to the nozzle plate to have a variable distance away from the nozzle plate, the valve plate having:
• at least one impact surface facing of the valve plate facing the nozzle plate, the at least one impact surface moving with the valve plate;
• a plurality of tapered control protrusions formed on the impact surface and each projecting towards a respective nozzle aperture;
• and
• tapering structuring projections arranged on the impact surface between adjacent ones of the tapered control protrusions, the tapering structuring projections having a length in the opening direction that is less than an opening direction length of the plurality of tapered control protrusions, the tapering structuring projections having a base arranged directly on the impact surface, and have a cross-section that continuously tapers from the base to an apex end;
• wherein the plurality of tapered control protrusions have a base arranged directly on the impact surface, and have a cross-section that continuously tapers from the base to an apex end of the plurality of tapered control protrusions;
• wherein the plurality of nozzle apertures each align in the opening direction to be receive the apex end of a respective one of the plurality of tapered control protrusions;
• wherein the impact surface with the plurality of tapered control protrusions are moved in the opening direction by a flow induced force acting against a pretension force of a pretension element, the movement dependent on a flow rate of the gaseous fluid through plurality of nozzle apertures, an amount of flow induced movement of the plurality of tapered control protrusions in the a plurality of nozzle apertures varying a flow cross-section of the plurality of nozzle apertures;
• wherein flow of the gaseous fluid through the varying flow cross-section of the plurality of nozzle apertures impacts against the tapering structuring projections, removing oil mist from the gaseous fluid.