Open Access

ARTICLE

A New Heat Transfer Model for Multi-Gradient Drilling with Hollow Sphere Injection

Jiangshuai Wang^1,*, Chuchu Cai¹, Pan Fu^2,3, Jun Li^4,5, Hongwei Yang⁴, Song Deng¹

1 School of Petroleum and Natural Gas Engineering, Changzhou University, Changzhou, China
2 CNPC Research Institute of Engineering Technology Co., Ltd., Beijing, China
3 National Engineering Research Center for Oil & Gas Drilling and Completion Technology, Beijing, China
4 College of Petroleum Engineering, China University of Petroleum (Beijing), Beijing, China
5 College of Petroleum, Karamay Campus, China University of Petroleum (Beijing), Beijing, China

* Corresponding Authors: Jiangshuai Wang. Email: ,

Fluid Dynamics & Materials Processing 2024, 20(3), 537-546. https://doi.org/10.32604/fdmp.2023.030430

Received 05 April 2023; Accepted 08 June 2023; Issue published 12 January 2024

Abstract

Multi-gradient drilling is a new offshore drilling method. The accurate calculation of the related wellbore temperature is of great significance for the prediction of the gas hydrate formation area and the precise control of the wellbore pressure. In this study, a new heat transfer model is proposed by which the variable mass flow is properly taken into account. Using this model, the effects of the main factors influencing the wellbore temperature are analyzed. The results indicate that at the position where the separation injection device is installed, the temperature increase of the fluid in the drill pipe is mitigated due to the inflow/outflow of hollow spheres, and the temperature drop of the fluid in the annulus also decreases. In addition, a lower separation efficiency of the device, a shallower installation depth and a smaller circulating displacement tend to increase the temperature near the bottom of the annulus, thereby helping to reduce the hydrate generation area and playing a positive role in the prevention and control of hydrates in deepwater drilling.

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Keywords

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