The invention particularly relates to a visualized experimental device for CHF research in a bidirectionally visible rectangular
narrow channel, belonging to the field of
flow boiling visualization research. The experimental device comprises fastening bolts, a
graphite gasket, flanges, a heating plate, a wide-side
quartz glass, a wide-sided bearing plate, a fluoro rubber
gasket, a narrow-sided
quartz glass, a narrow-sided bearing plate, a housing, a substrate, and a support column. The experimental device used in the invention is all
quartz glass on three sides, therefore, the behaviors of generation, aggregation, growth and detachment of bubbles on the heating surface can be observed from the side, and parameters such as a bubble layer and liquid film thickness can be measured; the heating plate is slightly narrower than the base, therefore, the rectangular flow channel
corner effect is avoided; the heating plate is shorter in axial direction than the substrate, therefore, the inlet and outlet effect is eliminated; the substrate is made of insulating
ceramic material, so that the heating plate is completely insulated from other parts of the experimental section; three support columns are welded on the heating plate and fixed to the substrate, so as to avoid expansion deformation of the heating plate at high temperature; and the flow path gap can be changed by changing the thickness of the
gasket between the wide-side quartz glass and the housing.