The invention relates to an apparatus, in particular for moving particles in a fluid at Reynolds numbers larger than 0.5, which comprises a container section adapted to hold said fluid, and which is adapted to perform a displacement process, which includes a number of repeated displacements of said container section, comprises at least one actuating device, which is adapted to perform said displacements, at least one connecting means, which connects said container section to said actuating device, said displacement comprising a first motion of said container section from a first position to a second position and a second motion of said container section from said second position back to said first position, wherein during said first motion said container section is at least temporarily moved with a first velocity, and wherein during said second motion said container section is at least temporarily moved with a second velocity, which is different from said first velocity, and wherein by means of said displacement process, a force is acting upon said particles in the fluid, which is capable of inducing a directed motion of said particles in relation to said container section, wherein said first and second velocity of said container section control, i.e. influence or determine, said motion of the particles. The invention further relates to a method for in particular moving particles in a fluid at Reynolds numbers larger than 0.5.