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I'm simming a 75mm minimum diameter design around a CTI M2245 Imax motor. It should reach speeds between Mach 2.6 and 2.9.
When I only change the shape of the nose cone between Conical and Von Karman, it makes about a 30% difference.
Conical: Mach 2.86, 15138 m high
Von Karman: Mach 2.64, 10680 m high
Sure, the wetted surface is less on the conical nose cone compared to the Von Karman, but I would assume that Rocksim also factors in other things like shock waves produced by the conical nose cone.
I often refer to this diagram when choosing a nose cone shape, and the Von Karman shape seems to be the best all-round shape, and better than a Ogive or Conical.
Can anyone tell me what's going on in Rocksim, why the huge difference? I've noticed that Rocksim also favors Conical nose cones in lower speed flights as well, under Mach 1.5. It seems improbable that Conical shapes would outperform a Von Karman shape.
Of course, I could try it in OpenRocket or RASAero.
When I only change the shape of the nose cone between Conical and Von Karman, it makes about a 30% difference.
Conical: Mach 2.86, 15138 m high
Von Karman: Mach 2.64, 10680 m high
Sure, the wetted surface is less on the conical nose cone compared to the Von Karman, but I would assume that Rocksim also factors in other things like shock waves produced by the conical nose cone.
I often refer to this diagram when choosing a nose cone shape, and the Von Karman shape seems to be the best all-round shape, and better than a Ogive or Conical.
Can anyone tell me what's going on in Rocksim, why the huge difference? I've noticed that Rocksim also favors Conical nose cones in lower speed flights as well, under Mach 1.5. It seems improbable that Conical shapes would outperform a Von Karman shape.
Of course, I could try it in OpenRocket or RASAero.