| Porous fluid distribution pipes are widely used in many fields about our gross national product. The main function of porous fluid distribution pipe is used to distribute the flow of fluid along the direction of the pipe, and using porous fluid distribution pipe can make the flow achieve uniformity.To obtain higher flow uniformity, it is necessary to factors associated with opening rate of experimental research. Based on previous research, to the flow uniformity of the main indicators, the opening rate as the main object of study, a lot of experiments are carried out. This paper considers the flow uniformity of the main indicators as the main indicators, and treats the opening rate as the main object of study, and conducts a lot of experiments based on previous research. The main conclusions are as follows:(1) According to the hypothesis of established model of the flow control volume, the paper can be drawn the corresponding respective orifice flow calculation formula. The reason why each out flow orifice flow changes in porous fluid distribution pipes is that the flow inside the pipe has been changing and that the changing of velocity inside the pipe is related with the position of orifice. So it concludes that the flow distribution of orifice discharge in porous fluid distribution pipe is connected with the changes of the flow rate along with the augment of the length, and also with opening rate. With the increase of opening rate the flow of orifice discharge in porous fluid distribution pipe will be also reduced.(2) After the analysis of a lot of experimental data, we obtain two important parameter values k,b based on the length of pipes and the expression of flow uniformity. In this paper, the concept of reasonable opening rate is putting forward; the computation expressions between flow uniformity and opening rate can be calculated by computational methods of reasonable opening rate in porous fluid distribution pipe. With the monotonicity of the function expression, the inverse function can be deduced. So the function expression of opening rate can be obtained when the uniform flow is known.(3) Application of the formula in this paper should pay attention to the ranges that the length of porous pipes is from 6 meters and 18 meters and the opening rate is from 0.000020 to 0.000900. Verified by the actual discovery, within the scope of application of the formula, the formula determined by the error between the actual flow uniformity and evenness of the flow are less than 5%.(4) This paper has a discussion of the reasonable laying length, and shows the derivation of specific details that it deduces the calculation formula of reasonable length in the condition of laying flat slope.(5) In this paper, the design method and procedure of the porous fluid distribution pipe system are presented in detail and the influence of pipes length and opening rate for system design is discussed. It is significance for improving the flow uniformity and refining the design system of porous fluid distribution systems that opening arguments are scientific and the flow distribution system is designed rationally. |
