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Old   September 8, 2011, 07:42
Default Negative Cd - drag
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I get negative values of Cd when I do simulation of airflow over sharp body. How can it be explained?
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Old   September 9, 2011, 13:43
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Hi

What does it look like your sharp body?
What is the value of negative Cd?
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Old   September 20, 2011, 08:22
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body is projectile shrapnel (random shape). Cd looks OK, but only negative. I used sine and cosine projections of streaming velocity so I guess that has something to do with it
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Old   September 22, 2011, 07:06
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I have found solution for this. When you correct values for Force componnents in Reports, then Cd is positive and OK.
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