Due to the translational motion of a bubble, droplet or particle, the pressure averaged over its surface is less than the bulk one. In the present study, the depressurization behavior of a spherical body is studied for various Reynolds numbers by the theoretical and the numerical approaches. A dimensionless number C
TDP, which is the depressurization scaled by the fluid density and the translational velocity, is defined. For a small but non-zero Reynolds number, the C
TDP is asymptotically obtained by the Stokes expansion method. The result shows that the C
TDP is finite and it is given by the function of the viscous ratio (μ
p/μ
f). The direct numerical simulation (DNS) is also conducted to obtain the C
TDP in the moderate Reynolds number. At the smallest Reynolds number (Re=0.1), the present DNS results of a clean bubble, a droplet and a rigid particle agree well with the present theoretical results. The C
TDP of a clean bubble monotonously increases with the Reynolds number and it approaches the solution of the potential flow (1/4) at the high Reynolds number. On the other hand, the C
TDP of a rigid particle does not monotonously increase with the Reynolds number and it has maximum value at Re∼O(100) due to the flow separation.
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