Popis: |
Interior ballistic prediction rely on submodels and submodel measurements. An important parameter is the coefficient of drag. These have been measured on the basis of steady flow through inert packed beds. Results have been presented in the form of coefficient of drag vs. Reynolds number divided by 1-4, where is the porosity of the bed. With improved statistical tools, it was felt that the existing data might be put into a form which would better reflect the actual measurements. In the report, we show that indeed this is the case. Minimizing the root-mean-square en-or (RMSE), a commonly used measure of the adequacy of fit, a new relationship is obtained. The new fit reduces the RMSE by 20%. |