Experimental and numerical investigation of the drag coefficients of subsea tree

The subsea tree acts as an important role in underwater production system. During its installation procedure, hydrodynamic loads significantly affect its dynamic performance. Hence, the drag coefficient of the subsea tree is addressed in detail in the paper by experiment and numerical simulation. Numerical simulation was carried out with finite difference method to get the drag force and drag coefficient. A new experimental method was proposed to conduct an array of model experiments for drag coefficient of subsea tree. The numerical results in drag coefficient were slightly different with experimental results, that was to say, the accuracy and reliability of the experimental data were proved. The drag coefficient is 0.432 in x-direction, 0.479 in y-direction and 0.446 in z-direction, which provide the accurate fundamental hydrodynamic data for underwater production system installation.