METHOD OF DETERMINING RAIN WASTE WATER CONSUMPTION Russian patent published in 2020 - IPC E03F1/00 

FIELD: sewerage.

SUBSTANCE: invention relates to water disposal. Method consists in that the estimation is carried out by a calculation method in eleven stages. At the first stage, rain network is traced, at the next step, the rain network is divided into n design sections. At the third stage, the drainage area is divided into n runoff areas so that each i-section of the rainwater network corresponds to the F_i^th flow area, i = 1, ..., n. Further, flow areas F_i are calculated, mean coverage coefficient Z_mid or average drain coefficient ψ_mid, determined respectively as weighted average values depending on values of coating coefficients Z_i for various types of coatings or as weighted average values of Ψi for different types of catchment surface. Then, value P of single exceeding of calculated rain intensity, year is selected. Then, calculated rain intensity q₂₀ of duration 20 minutes, l/s-ha, and reference parameters: n, Y are dimensionless parameters depending on geographic location of the area; m_r is average amount of rains per year depending on geographic location of the area. At the eighth stage, depending on the time t_p of rainwater runoff through the pipes to the calculated cross-section, the specific consumption q_con is determined from the unit area as per the relationship q_con = f₁(q₂₀, Z_mid, P, n, Y, m_r, t_r) or by the relationship q_con = f₂(q₂₀, ψ_mid, P, n, Y, m_r, t_r), where t_r is design rain duration, min; t_r = t_con + t_can + t_p, where t_con is time of surface concentration, min; t_can is time of rainwater run-through on street trays, min; t_p is time of rainwater run-through to the section to be calculated, min. At the ninth stage, depending on the time t_p of rainwater run-off through the pipes, a plot of the specific consumption q_con = f₁(q₂₀, Z_mid, P, n, Y, m_r, t_r) is plotted to the calculated cross-section, or graph of specific consumption q_con = f₂(q₂₀, ψ_mid, P, n, Y, m_r, t_r) at constant values q₂₀, Z_mid, ψ_mid, P, n, Y, m_r, t_con, t_can. Further, determining for any i-section of rain network reference coefficient βi, taking into account the filling of free capacitance of network at the moment of pressure mode occurrence, time t_pi of rainwater runoff through pipes to the section to be calculated, and determining, based on one of the plotted q_{con i} diagrams, for any i-section of the rain network, consumption qi of rainwater by formula q_i = B_i * q_{con i} * F_i, where B_i is design factor considering filling of free capacity of i-section of rain network at moment of pressure mode occurrence. Additionally, maximum actual q_20f rain intensity is determined for 20 minutes during actual or forecast rain, as calculated rain intensity q²⁰ is taken to actual q^20f rain intensity, and the design factor Bi, taking into account the filling of the free capacity of the i^th section of the rain network at the moment of occurrence of the pressure mode is determined by the function B_i = f₃ (q_20f), the value of which at q_20f = q₂₀ is equal to or close to the value of β_i.

EFFECT: wider range of application.

1 cl, 11 dwg