The invention provides an adding method and a device suitable for conveying experimental large particles in a
solid-liquid two-phase flow, which are characterized in that: the device comprises a
particle injection hopper, a two-phase fluid return pipeline with
branch pipelines and a
liquid storage tank. The
particle injection hopper is mounted in the
liquid storage tank; the
particle injection hopper is connected with a pump suction pipeline inside the
liquid storage tank through a particle injection pipeline; a
gate valve with a filter screen is mounted between the particle injection hopper and the particle injection pipeline; a filter screen is arranged at a liquid-phase suction section of the pump suction pipeline inside the
liquid storage tank; the liquid-phase suction section of the pump suction pipeline inside the
liquid storage tank sucks in liquid in the
liquid storage tank; a two-phase fluid return
branch pipeline and a liquid return
branch pipeline are arranged on the two-phase fluid return pipeline; the two-phase fluid return branch pipeline is used for returning
solid-liquid two-phase fluid to the particle injection hopper; and the liquid return branch pipeline returns partial liquid to the liquid
storage tank. According to the method and the device, the device has a simple structure, the adding and the recycling of the large particles are convenient, the concentration of the particles is convenient to control, the mixing of the particles is even, and the pipelines are convenient to flush.