Method for preparing fluid with layered density

The invention discloses a method for preparing fluid with a layered density. The method for preparing the fluid with the layered density can provide a simple and effective layering technology for ocean layered environmental laboratory simulation. According to the method for preparing the fluid with the layered density, the water outlet flow of a fresh water tank and the water outlet flow of a brine tank are controlled with an automatic control method; a mixer is arranged to enable brine and fresh water to be fully mixed; a booster pump is arranged to enable the brine and the fresh water to flow into a layered water pool at a controllable speed, so that layered fluid is formed; the opening degree of an electrically-operated valve is regulated with the PID technology, the rotating speed of the booster pump is regulated through a frequency converter, a dual-regulation method is formed, the flow of the brine and the flow of the fresh water are accurately controlled and are regulated according to a preset flow cha