The water jet flow model in the hydroentanglement nonwoven process is established and solved numerically. The impact force of water jets is calculated with aid of the model and verified with the experimental data. The numerical simulation results of the impact force coincide with the experimental data, which confirms the effectiveness of the two-dimensional model established. Computer simulations and experiments show that higher water jet pressure, smaller water jet inclination angle, and smaller standoff distance will yield larger impact force. The results show that there is great potential for this research in field of computer-assisted design in hydroentanglement technology and equipment. POLYM. ENG. SCI., 50:2425-2430, 2010. (C) 2010 Society of Plastics Engineers