Can anyone explain the difference between ogive and VK in layman's terms?

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Bat-mite

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I don't want crazy math, just a general description of how a von Karman is shaped compared to an ogive. Thanks.
 
an ogive (specifically the tangent ogive) is made up of a section of a circle where the base of the cone is tangent to the body, and the base of the cone is on the radius of the circle.

Von Karman (and Haack series) shapes are not derived from geometric shapes (like the circle example above) but are made by plugging values into formulas to reduce drag. The Von Karman shape is the one giving minimum drag for the given length and diameter of the cone.

kj
 
an ogive (specifically the tangent ogive) is made up of a section of a circle where the base of the cone is tangent to the body, and the base of the cone is on the radius of the circle.

Von Karman (and Haack series) shapes are not derived from geometric shapes (like the circle example above) but are made by plugging values into formulas to reduce drag. The Von Karman shape is the one giving minimum drag for the given length and diameter of the cone.

kj

Specifically, the Von Karman and Haack shapes minimize what's called "wave drag" which is caused by the nature of supersonic flows. I believe that they are optimized for different Mach numbers, but I don't know what those numbers are.

For reference, the primary mode of drag on a subsonic nose cone would be "skin drag," cause by the fact that the air right next to the nose isn't moving at all (relative to the nose cone). This creates a shear in the air that robs the flow of energy.
 
you can download Key Payza's spreadsheet from my website and see for yourself. The Von Karman is a special form of the Haack.
 
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