Study On Discharge Capacity Under The Influence Of Drainage Riser Offset On Drainage System In High-rise Residential Buildings

The functional structure of modern high-rise buildings is complex,in order to avoid the structural obstacles inside the building,the direction of the drainage pipeline is easily restricted,but there is no evidence that this type of pipe installation will affect the safe use of the drainage system.Therefore,this paper takes the drainage system of high-rise residential buildings as the research object,through full-scale experiments and numerical simulation methods,to study the influence of the axis offset of the drainage riser axis of high-rise residential buildings on the water flow capacity of the drainage system.The research content and results of the thesis are as follows:The full-scale experiment is operated at the 60-meter-high Xuanshi Tower of the National Construction Drainage Pipeline Experimental Center in Gaoping City,Shanxi Province.With a constant flowrate,an experiment was carried out on the offset of the drainage riser at the axis in accordance with the " Standard for testing the Drainage Capacity of the rise of Residential Drainage System."(1)Install the S-shaped offset pipes between the 4th and 5th floors of the double stack drainage system(the diameter of the drainage riser is DN150 and the diameter of the vent pipe is DN100)with anti-reflux H pipe installed every other floor.The experiment found that the existence of the S-shaped offset pipes will greatly reduce the water flow capacity of the system.From the perspective of pressure distribution,the offset mainly affects the pressure on the floor above the installation location,resulting in severe positive pressure.Under the same conditions,changing the length of the offset pipe section,the results show that: the longer the offset distance,the smaller the drainage capacity of the system.(2)Exploring the optimization method for the negative impact caused by the offset of the drainage riser through actual measurement experiments.Perform a full-scale test on a system where the diameter of the drainage riser and the vent riser are both DN100,change the curvature of the elbow,the slope of the offset pipe section and the size of the pipe diameter at the offset position at the junction of the drainage riser and the offset horizontal pipe section,and take the regular offset installation as the control group,experimental results showed that the use of large curvature elbows can achieve better optimization results,and the installation of an anti-reflux H pipe above the offset position can also increase the maximum water flow capacity of the system.(3)Using the software Fluent to study the impact of the optimization method on the interior of the system,the results show that the large curvature elbow can improve the water flow state at the offset position and make the water flow more smoothly;and the additional anti-reflux H pipe can improve the ventilation of the system condition,evacuate the positive pressure at the location.