Design method of underflow manual wetland matrix structure based on flow field distribution

The invention discloses a design method of an underflow manual wetland matrix structure based on flow field distribution. The method performs quantification design on main structural parameters influencing underflow manual wetland flow field distribution based on a seepage field theory, taking uniform distribution of a water flow around a bed body as a purpose, and taking a three-dimensional finite difference underground water flowing mathematical model as a design calculation basis, wherein the main structural parameters include manual wetland unit division, unit pond body length-width ratios, water distribution area length, water collection area length, bed body depth, filling layers of a main body filler area, and filler permeability coefficients; matrix fillers are measured by a Darcy permeability test; the fillers with required particle size are screened out. When the design method performs design calculation on the structural parameters of underflow manual wetland, the selection of the structural parameters is simple, convenient and practicable; the underflow manual wetland constructed according to the design method can greatly improve and increase the hydraulic efficiency of a system and utilization ratios of the fillers, can avoid a channel flow, a short flow and a dead area, and can further improve and prolong a purifying effect and the service life.