| Petroleum pipeline inspection robot is special equipment for the long-transport petroleum pipeline, which is used to inspect defects and maintain the pipeline. Pipeline robot is a mechatronics device which is able to carry various kinds of inspection devices in restricted space and complete inspection task under the remote control of the operator.Our country is in a period of rapid economic growth. Oil and gas are the economic artery for a state and region, thus keeping the oil and the gas in normal operation is crucial for economic benefit. The long-transport pipeline are buried underground with a depth of 1.5m～2m. The length varies from several hundred kilometers to several thousand kilometers. Pipeline robot can inspect various kinds of defects and geometrical deformation on line and pinpoint the defection's exact location, which provide information for the pipeline's safety and maintenance.From a global view, the advanced pipeline robot technology is monopolized by America, Germany, Japan, Norway etc. They only provide the expensive online inspection service but don't sell the technology and product. From a domestic view, the research of the pipeline robot is just at its initial step. Although some progresses have been achieved, it is still a long way towards the practical application. So developing the pipeline inspection device and having the proprietary intellectual property rights are of vital important.This paper carried out some basic research for the development of the domestically developed pipeline robot at the background of the Daching petroleum administration key scientific and technological project: the"The research of the pipeline robot for the corrosion intelligent inspection of the buried steel pipeline". As the pipeline robot works in the fluid situation, the flow fluid around the robot has the great influence on the performance of the robot. This paper uses computational fluid dynamics (CFD) to analyze the flow fluid using three dimensions numerical simulation under some kinds of working conditions. In order to verify the numerical simulation result, the experiment with the PIV particle velometer system was used to test the flow fluid speed in the condition of robot model working in the straight pipeline.The major content of the paper are as follows: (1) Review of the development of the pipeline robot domestic and abroad. Sum up the information of the flow fluid simulation around the robot and the corresponding research methods of the experiment.(2) Expound the system composition, configuration, the principle of work of the pipeline robot. According to the technical requirements of the Taching research project, build a three-dimension solid model of the double joint petroleum pipeline robot and analyze the main reference configuration.(3) Use the computational fluid dynamics (CFD) to do the three dimensions numerical simulation of the pipeline robot work area's flow fluid and expound the governing equation and arithmetic.(4) With Large amounts of welding line and accessories exiting in the petroleum pipelines and getting affected by the pipeline corrosion and pipeline adherence etc., the inside situation of the pipeline is very complex. Analyzing the in-field situation, the paper proposes four special types of flow passage and builds the respective solid models. Use CFD preliminary treatment to divide the grid and set the boundary conditions. Import the model to the CFD software, choose the arithmetic and set the computation model to do the numerical simulation. In order to get more accurate simulation of the robot work area's flow fluid situation, programming the pipeline inlet conditions.(5) After the CFD software numerical simulation, four types of flow passages'flow fluid distribution character were got. Comparative analyze the entire flow passage and the special section plane of the four types of flow passages'velocity and pressure, and study the driving force of the straight pipeline start-up condition.(6) In order to verify the accuracy of the CFD numerical simulation results, use PIV particle velometer system to test the speed as the robot works in the straight pipeline. Compare the experimental velocity distribution results of the flow fluid with the numerical simulation results in the qualitative and quantitative aspects, the two different results fit close at the range of the permissible error.According to the experimental verification, the numerical simulation results are reliable, which can simulate the petroleum pipeline robot working area's flow fluid distribution character. The study of this paper has great significance for the research of the robot optimization configuration, material option and device setting etc. |
PDF Full Text Request