The waste heat emissions of thermal discharge from floating nuclear power plants may have a negative thermal effect on the environment.Investigation on the buoyant and diffusion rules of thermal discharge from floating nuclear power plants and properly controlling the discharging temperature have great significance for seat water thermal pollution prevention.This paper simplified the thermal discharge process as thermal jet in cross flow to establish the 3Dmathematic model for thermal jets floating process

on the basis of finite volume method and using the SIMPLE algorithm and Realizable k-εturbulence model.Then this model was verified by using the experimental data from reference[5].The thermal effect range and degree of environmental velocity and discharge angle on thermal discharge were investigated.The results show that

at high ambient velocities

the convection heat transfer was intense so that the heat-affected zone was influenced less by the emission angle

while at low ambient velocities

the influence of emission angle increased remarkably due to the weakness of ambient currents scouring effect.Under the same conditions

change of emission angle in vertical plane had less effect on the central temperature along stream

and it had dramatic effect when the plane was parallel to the stream.The environmental velocity had a little effect on the central temperature along the stream.