Optimization Research On Pipe Network Construction Scale Of Drip Irrigation Engineering

The development history for the construction of drip irrigation engineering in Xinjiang has experienced several decades,and has built some pipe network projects for a variety of scale,with the continuous de velopment of the treatment technology for channel silt and has been matured gradually,the pipe network construction scale has increased gradually and the control area boundary has exceeded 200 hm~2,even exceeded 667 hm~2.Therefore,with reasonable analysis and demonstration for the factors including control are a of dripirrigationpipe network and the investment?operation?management cost of drip irrigation system,and with the net present value method to reasonably evaluate the loading drip irrigation engineering of different construction scale,the paper provide the factual basis for the construction scale of drip irrigation pipe network and promote a new stage for the understanding of the construction scale of drip irrigation pipe network in Xinjiang.The main results are as follows:The paper stated the layout and calculation formula for the drip irrigation pipe network,select the cal culation formula and economic indicators with the maximum length of hair canal during the design process to determine the most economical length of the hair canal layout.The results showed that the economic length for hair canal layout is more with the increasing of dripper spacing and the decreasing of dripper flow under the same hair canal spacing,also less with the increasing of irrigation area.The paper analyzed the influence of the investment within five structural parts for drip irrigation engineering(including the investment of water source project?dynamical system of head work?main pipe network?farmland pipe network and self-financing)on the total investment of the project based on theory analysis of the actual design example,got that with the large system,the water transportation and distributing pipe has more level?longer?larger diameter and the higher equipment grade,so lead to the more cost of pipe network;if the system is too small,the head work control system cannot be fully used because of the optional equipment control,the cost proportion for the head work system is relatively increased;with the technical analysis for using net present value method of engineering economics,calculate and discount to the initially present value and compared with every construction scale,from the per spective of average investment for per unit and with its net present value,it is concluded that the construction scale with about 133 hm~2 is the most reasonable investment projects.The paper provides some constructive ideas on finding an optimal and economical solution in the hair canal selection of length and construction scale of drip irrigation.The optimal control area is determined rationally under the consideration of the economic factors,to maximize the efficiency?provide reference and guidance for the benign development of the drip irrigation engineering in Xinjiang.