Research On Sensor Network Monitoring Technology For Subsea Production System

With the shift of oil and gas exploitation emphasis from shallow water to deep water,the traditional subsea production system is no longer suitable for the exploitation of deep water oil and gas resources,due to its difficulties in installation,high operating costs and poor communication reliability.How to design a new subsea production system suitable for deep water environment with good economic benefit and easy control is of great significance.The new subsea production system based on function module proposed by the project has the characteristics of fully autonomous control and unattended in the whole subsea production condition.The precondition for realizing this system lies in the real-time monitoring of the working condition data of the system.In this paper,the cabin of the function module is simplified to a regular cylinder,and the side of the simplified model is determined as the research object.The wireless sensor network is used to cover the area to be monitored in the function module.Firstly,the node deployment rule and coverage parameter calculation of the regional coverage network are studied.Secondly,the method of constructing and optimizing the coverage set in the random coverage network is studied.Finally,the detection method and repair strategy of coverage holes are given simply for the regional coverage network and the random coverage network in this paper.In the research of area coverage network,the coverage density and coverage efficiency of sensor nodes in the network are mainly studied.By comparing the existing literature,the isosceles triangle node deployment method is selected.The monitoring area is divided into sub-zones with equal width.Based on the common isosceles triangle method,the starting point of coverage parameter calculation is improved by extending the bottom edge length of isosceles triangle.The calculation starting point of coverage parameters is redefined.The result shows that when the width radius ratio of the new method is 0.867,the minimum of single coverage density and double coverage density are obtained.The coverage density and coverage efficiency are better than those of the conventional method,and the comprehensive performance index is better.The influence of ocean factors such as temperature and pressure on coverage network is also analyzed.In the research of random coverage network,the coverage set is mainly built on the basis of dangerous points,the factors affecting the network lifetime are analyzed,and the evaluation function is constructed with positive and negative correlation coefficients to optimize the network with low value of evaluation function and low utilization rate of nodes.The influence of node perception radius and number of nodes on network performance is analyzed through experiments.The results show that this method performs better in prolonging the network lifetime when the number of nodes is greater than 180 and the sensor radius is greater than 2400 mm,except for the influence of random factors.The influence of ocean factors on the coverage performance of stochastic networks is further analyzed.In the maintenance of the latter network,the particularity of the area coverage network and the random coverage network is studied in this paper.The detection method of coverage hole based on neighbor nodes of reference nodes is given,according to the particularity of node deployment method,the repair method of activating eligible related nodes is given.Through the above analysis and research,we can get the method of comprehensive area coverage and random target coverage on the side of the cabin of function module by using sensor node network,which can be used to monitor the deterministic and random factors affecting the normal operation of the function module,and the corresponding detection and repairing methods can also be adopted for the later generation of coverage holes.