Fixed-cone valves are generally used to regulate flow under medium to high water head conditions because of their ability to safely and efficiently pass the flow. By designing, fixed-cone valves, also known as Howell–Bunger valves, emit a large-diameter conical spray. The spray is effective in spreading and dissipating energy, although in some conditions where space is limited, it may be desirable to contain the spray. Containing the spray may be achieved by using a hood; however the result is a high velocity hollow jet that focuses the energy in the stilling basin. Depending on the size of the stilling basin downstream of the valve and the sensitivity to environmental factors, it may be necessary to dissipate some energy of the concentrated jet prior to impingement in the stilling basin. This paper is concerned with a numerical two-phase flow model combining with the Realizable k–ε turbulent model for simulation of flows around a fixed-cone valve. The equations were solved with the finite volume method. The function of the fixed-cone valve for energy dissipating was pointed out by analyzing the computed pressure field, velocity field of the fixed-cone valve by the proposed model. The simulating results show that the proposed model is reliable and can be applied to the numerical simulation of turbulence flow around a fixed-cone valve.