The drag coefficient of a solitary particle when moving relative to a fluid, when rising or falling vertically in a stationary fluid, is a well-known function of the particle Reynolds number.
Reference:
Bonapace, A. 1971. The drag coefficient of a particle and the voids fraction in fluidization or sedimentation assembly of particles. http://hdl.handle.net/10204/13031 .
Bonapace, A. (1971). The drag coefficient of a particle and the voids fraction in fluidization or sedimentation assembly of particles Retrieved from http://hdl.handle.net/10204/13031
Bonapace, AC The drag coefficient of a particle and the voids fraction in fluidization or sedimentation assembly of particles. 1971. http://hdl.handle.net/10204/13031
Bonapace A. The drag coefficient of a particle and the voids fraction in fluidization or sedimentation assembly of particles. 1971 [cited yyyy month dd]. Available from: http://hdl.handle.net/10204/13031