High-resolution hydrodynamical simulations are presented to follow the gravitational collapse of a uniform turbulent clump, upon which a purely radial compressive velocity pulse is activated in the midst of the evolution of the clump, when its turbulent state has been fully developed. The shape of the velocity pulse is determined basically by two free parameters: the velocity V0 and the initial radial position r0. In the present paper, models are considered in which the velocity V0 takes the values 2, 5, 10, 20, and 50 times the speed of sound of the clump c0, while r0 is fixed for all the models. The collapse of the model with 2 c0 goes faster as a consequence of the velocity pulse, while the cluster formed in the central region of the isolated clump mainly stays the same. In the models with greater velocity V0, the evolution of the isolated clump has significantly changed, so a dense shell of gas forms around r0 and moves radially inward. The radial profile of the density and velocity and the mass contained in the dense shell of gas are calculated, and it is found that (a) the higher the velocity V0, the less mass is contained in the shell, and (b) there is a critical velocity of the pulse, around 10 c0, such that, for shock models with a lower velocity, there will be a well-defined dense central region in the shocked clump surrounded by the shell.
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