Arch Appl Mech (2017) 87:1439–1451 DOI 10.1007/s00419-017-1262-9 ORIGINAL Jialin Tian · Yinglin Yang · Lin Yang Vibration characteristics analysis and experimental study of horizontal drill string with wellbore random friction force Received: 28 October 2016 / Accepted: 17 May 2017 / Published online: 1 June 2017 © Springer-Verlag Berlin Heidelberg 2017 Abstract For the nonlinear vibration of the drill string in the drilling process, vibration characteristics anal- ysis and experimental study of the drill string are conducted, which are to analyze the drill string dynamic characteristics with wellbore random friction force on the basis of the horizontal well. Firstly, considering the wellbore random friction force, the analysis models of the drill string vibration and the drilling efficiency of the horizontal well are established. Then, the establishment method of the random wellbore friction field is also obtained. With the combination of solution expressions of each force in the vibration equation, the discrete method of the dynamic model is established. According to the experimental test, the key input parameters are determined, and then, the example analysis of the vibration model is conducted. With the comparison of the experimental test and theoretical calculation, the influences of key parameters on the dynamic characteristics of the drill string are analyzed to verify the accuracy of the analysis model. The results can provide a new insight to the researches of the drill string dynamics, especially for the complex well, such as ultra-deep well, branch well and directional well, in which the wellbore friction has a significant influence on the result of the drill string kinetics. Moreover, the results can offer an important guidance for the design and application of new downhole tools. Keywords Vibration · Drill string · Drilling · Random friction · Dynamics · Analysis model 1 Introduction With the depletion of conventional oil and gas resources, new hydrocarbon resources are exploited gradually, such as shale gas, coal-bed gas, and the drilling engineering faces more complex formation environment. Based on the existing drilling technology, directional well, horizontal well and multilateral well are developed and applied rapidly. For example, with the increase in the target diameter of the extended reach well in the exploitation of the shale gas, the dynamic characteristics of the drill string are influenced by wellbore friction in a growing proportion, and existing research methods and conclusions cannot meet the actual needs [1–3]. The analysis of the wellbore friction randomness and the research of the drill string dynamics have important significances for the development of the exploitation of new hydrocarbon resources and the increase in the drilling technology of the complex well. J. Tian (B ) · Y. Yang · L. Yang School of Mechatronic Engineering, Southwest Petroleum University, Chengdu 610500, China E-mail: tianjialin001@gmail.com Y. Yang E-mail: 291823157@qq.com J. Tian School of Mechanical Engineering, Southwest Jiaotong University, Chengdu 610031, China