Simulation And Optimization Of Non-negative Pressure Variable Frequency Water Supply System Of High-rise Buildings

Nowadays,most of the buildings are high-rise buildings,because of the number of floors,leading to its water demand and energy consumption.According to relevant research,Compared with other traditional secondary water supply modes,non-negative pressure water supply mode has a higher energy saving rate and can also avoid secondary pollution.Therefore,it is of great significance to study the optimization and energy-saving transformation of the nonnegative pressure water supply system.This paper takes the practical project,which is a small community in LeShan,located in SiChuan province,using FLOWMASTER as the platform,which is a one-dimensional fluid simulation software,taking the high-area water supply system of this project as an example,respective establishing the model of transfer tank + variable frequency constant pressure water supply system,non-negative pressure + variable frequency constant pressure water supply system,non-negative pressure variable frequency water supply system under different municipal pipe network pressure,non-negative pressure variable frequency water supply system after optimization,After the simulation,coming to these conclusions:1.The energy consumption of the water supply pump in three different water supply modes is ranked as follows: variable frequency variable pressure < variable frequency constant pressure < constant speed.The the energy saving effect of variable frequency variable pressure mode is the best,but the feasibility and economy are low.Therefore,the variable frequency constant pressure water supply is generally chosen.2.Under the same working condition,the energy saving rate of the non-negative pressure equipment + frequency conversion constant pressure water supply system is higher than that of the water tank + frequency conversion constant pressure water supply system,which is 32%.3.In the non-negative pressure variable frequency and constant pressure water supply system,the two measures of limiting the use conditions of the non-negative pressure water supply equipment in the surrounding buildings and installing pressure sensors and signal butterfly valves in the water inlet pipe can be adopted to reduce the fluctuation range of pressure value on the municipal water supply pipe network when the water consumption of users changes.4.Through the simulation calculation,the original non-negative pressure variable frequency water supply system can be added with a small flow pump whose flow rate is 26% of the original pump flow rate,which is specially used for the water supply in the low water consumption period.The optimized water supply system with a small flow pump can save 55% of the energy Compared with the previous one.The above conclusions can provide reference for practical engineering.