Research On The Two-phase Flow Characteristic Of Urban Original Sewage

Urban Sewage contains enormous energy and it can ease pressure on the heating andcooling energy consumption of buildings when being used by sewage-source heat pumps to alarge extent. Nowadays, most of researchers have taken emphasize on the value and prospectof the sewage source heat pump, but paid little attention to the flowing characteristic, and thisaspect has been lack of basic study. The flowing characteristic of the sewage source heat pumpis a very important problem in the calculation of the system’s hydraulic and heat transfercalculation, and it is the key problem of the steady operation. Because of lacking of study inthe flowing characteristic of the sewage source heat pump the design rule in the pipe and heattransfer equipment has not established. Focused on the two-phase flow characteristics of theurban original sewage, this paper studied the characteristics of two-phase flow, critical velocity,motion of the particles when sewage flowing in pipe and channel of heat pipe exchanger.These will supply base ground for the application and popularization of urban sewage sourceheat pump.Because the urban original sewage’s water quality is very complex, sewage source heatpump technology is confronted with many difficulties and challenges. This paper starts fromthe characteristics of sewage flowing, focusing on the characteristics of wastewater flow byusing the theory of two-phase flow, experiment, numerical simulation of Fluent. Because oflow velocity, most of the sewage particles has been settling tube bottom in laminar flow. Thenthe suspension is homogeneous fluid, can be analyzed by the non-Newtonian fluid model.However, it is in the high velocity turbulence, a large number of particles will remain insuspension, can be analyzed by the two-phase fluid model. Finally, I have got the sewage’svelocity distribution and calculation method of resistance loss which providing the referencefor the sewage source heat pump system about design and hydraulic calculation.The flow characteristics of sewage water which flowing in a heat pipe exchanger isanalyzed in this paper. The channel consist s of the heat pipe which is side by side, in whichfluid flow. In order to understand the flow characteristics of sewage water flowing in thespecial channel, this paper analyzes the influence of heat pipe size, cross-sectional shape,velocity magnitude. These studies are helpful to the optimization design of the heat pipeexchanger.The problem of Piping and heat exchanger fouling and plugging has been hindering thedevelopment of sewage source heat pump. This paper analyzes the trajectory of particles indifferent section shapes and different velocity from the basic principles of scaling. That willprovide the basis for the scale of sewage source heat pump system. In a word, the researches and analysis of the urban original sewage characteristics oftwo-phase flow in this paper, which supporting supply to design, management of system andfurther study of sewage source heat pump. All of the research in this paper provides the theorybasis for further research on sewage source heat pump technology.