A Sewer Dynamic Model for Simulating Reaction Rates of Different Compounds in Urban Sewer Pipe

A sewer dynamic model (SDM), an innovative use of combined models, was established to describe the reactions compounds in a pilot pipe. The set ordinary differential equations SDM solved simultaneously using fourth-order Runge–Kutta algorithm. validated by calculating consistency between simulation and observation values. After validated, reaction rate analyzed. For heterotrophs water phase biofilm, their growth rates were greater than organism decay rate. ammonia, supply consumption at initial time, but smaller from 3rd hour. for other six compounds. oxygen before 4th hour because microorganism activities, and, subsequently, after reaeration. results this study provide insight into different urban pipes network modeling reference policymaking regulation.