Convective forces in high precision mass measurements

The paper deals with a numerical simulation of the natural convection air flow and its influence on ap- parent mass in high precision mass measurements. Results are in reasonable agreement with the expe- rimental values obtained on a 1-kg silicon sphere and a 1-kg mass standard. There is clear evidence that the three-dimensional finite element model studied, allowing inclusions of the boundary and initial conditions determined experimentally, captures the most important features of convection and estimates the relevant corrections.