Review
Energy & Fuels
Zhimin Yao, Yangyang Zhang, Yuanzhou Zheng, Chenghao Xing, Yun Hu
Summary: This paper reviews the current research on reducing wax precipitation and enhancing crude oil flow in offshore pipelines, investigating methods such as reducing viscosity and strengthening process technology. Areas in need of further research are also identified and discussed.
JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING
(2022)
Article
Thermodynamics
U. K. Zhapbasbayev, G. I. Ramazanova, D. Zh Bossinov, B. K. Kenzhaliyev
Summary: The study focuses on the transportation of waxy oil in industrial pipelines, using pour point depressants to decrease pour point and increase fluidity for effective transportation. Through numerical methods, continuity, momentum, and energy equations were solved, and the theoretical analysis was verified with experimental data, confirming the effectiveness of pour point depressants for pumping waxy oil at temperatures below pour point.
CASE STUDIES IN THERMAL ENGINEERING
(2021)
Review
Energy & Fuels
Weidong Li, Wenda Wang, Jirong Ran, Huiyuan Li, Jianxun Liu
Summary: This paper focuses on the issues in flow assurance of crude oil pipeline transportation, particularly on pig stalling and wax blockage. By extensively surveying multiple field pigging operations, it summarizes the experience and lessons obtained from these incidents. The drawn experience and lessons are helpful for scheduling pigging program and enhancing the security of pipelines.
PETROLEUM SCIENCE AND TECHNOLOGY
(2022)
Article
Mathematics
Lan Zhang, Jing Wen, Ming Liu, Guangzhen Xing
Summary: The importance of the real contact area of rough surfaces in engineering applications is discussed, and a revised continuous observation length model is proposed to analyze the influence of different observation lengths, fractal dimensions, and elastic moduli on the contact area.
Article
Energy & Fuels
Hanqing Zhang, Huiyuan Li, Weidong Li, Jianguang Wang, Wenda Wang, Yongjuan Zhang, Lin Teng, Pengbo Yin, Xin Huang
Summary: Mechanical pigging is a common wax removal technique in crude oil pipeline transportation. A superparamagnetic nanoparticle pigging system has been designed to soften wax deposits and reduce resistance, improving pigging efficiency.
Article
Energy & Fuels
Xuedong Gao, Qiyu Huang, Xun Zhang, Yu Zhang, Xiangrui Zhu, Jinxu Shan
Summary: In this study, the wax removal physics of foam pigs was experimentally investigated, and a five-phase description of wax resistive force was proposed; the effects of foam pig density, wax yield stress, and wax layer thickness on the wax removal efficiency were further discussed.
JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING
(2021)
Article
Energy & Fuels
Jing Huang, Jinjun Zhang, Wenwen Liu, Yiwei Xie, Qian Huang, Hongying Li
Summary: In this study, adhesive and cohesive fractures were identified as two possible modes of fracture during yield stress measurement of materials such as waxy oil gel. The balance between cohesive strength versus adhesive strength was found to determine the fracture mechanism of gel in the yield stress measurement, while oil composition and test conditions may influence one or both of these strengths.
Article
Energy & Fuels
Yifan Gan, Qinglin Cheng, Shengli Chu, Zhihua Wang, Guohua Luan, Wei Sun, Shuang Wang, Chao Liu, Qibin Li, Yang Liu
Summary: The research established a molecular dynamics model to characterize the deposition and wall sticking behavior of waxy crude oil pipeline transportation, with the proposed equal density interpolation fitting method for determining wall contact angle. The study verified the model's accuracy and reliability by comparing simulation results to experimental data, and investigated the micro influence mechanism of surface free energy on adhesion behavior and the selective deposition process of waxy crude oil on the sedimentary layer.
Article
Energy & Fuels
Yuchuan Chen, Bohui Shi, Shunkang Fu, Qingping Li, Haiyuan Yao, Yang Liu, Xiaofang Lv, Junao Wang, Qingyun Liao, Xu Duan, Jing Gong
Summary: This study investigated the impact of wax crystals on hydrate formation and rheological properties of hydrate slurry through rheological experiments, revealing that both wax content and water cut affect the formation and growth of hydrates. Semi-empirical models were proposed to describe the inhibitory effect of wax crystals on hydrate nucleation kinetics. The study also found that the maximum values of hydrate slurry viscosity rate and calculated hydrate effective volume fraction decreased with increasing wax content, and hydrate growth time was extended with higher wax content.
Article
Engineering, Chemical
Haizatul Hafizah Hussain, Shaharin Anwar Sulaiman, Girma Tadesse Chala, Hazlina Husin
Summary: Transportation of waxy crude oil often faces flow assurance issues, such as wax deposition, which leads to operational complexity during pipeline restart after shutdown. This study investigates the effect of crude oil and nitrogen gas flow rates on the time taken for crude oil flow initiation. Results show that the presence of nitrogen gas improved pipeline restart phase by reducing both restart pressure and flow initiation time.
Article
Energy & Fuels
Hongying Li, Chaohui Chen, Qian Huang, Yifei Ding, Yu Zhuang, Yiwei Xie, Miaomiao Xu, Shanpeng Han, Jinjun Zhang
Summary: Treatment with pour point depressant (PPD) can reduce the impedance changes caused by wax precipitation, making waxy crude oil easier to transport. Addition of PPD leads to increased capacitance and decreased resistance of wax particles, with a positive correlation between the viscosity reduction and the decrease in resistance. This study provides new insights into the functional mechanism of PPD in improving the flowability of waxy crude oil.
Article
Energy & Fuels
Yang Liu, Xiao-Fang Lv, Qian-Li Ma, Shi-Dong Zhou, Bo-Hui Shi, Hui Du, Yun Lei, Peng-Fei Yu, Shang-Fei Song, Jing Gong, Bing-Cai Sun
Summary: This study elucidates the synergistic effect of wax and hydrates and its impact on the operation and transportation safety of offshore petroleum fields. Different plugging scenarios and flow properties were observed in systems with varying wax contents. The presence of wax deteriorated the performance of anti-agglomerant, and the wax deposition layer altered the adhesion and bedding of hydrates, resulting in variations in flow properties and wall deposition state. A physical model for the synergistic deposition of wax and hydrates was presented, which is valuable for risk analysis and blockage prediction.
Article
Energy & Fuels
Guillaume Vinay, Petrus Tri Bhaskoro, Isabelle Henaut, Mior Zaiga Sariman, Astriyana Anuar, Siti Rohaida M. Shafian
Summary: Waxy crude oil pipelines are prone to gelation, which can potentially block the pipeline, and accurate prediction of restart pressure is crucial for safe operation and cost-effective mitigation strategies. Various improved restart pressure calculation methods have been proposed, with the original methodology developed by IFPEN showing the ability to provide a more realistic description of gel strength variation along the pipeline.
JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING
(2022)
Article
Chemistry, Multidisciplinary
Sachin Balasaheb Shinde, Lomesh Tikariha, Lalit Kumar
Summary: Flow assurance challenges associated with waxy crude oil precipitation at low ambient conditions are significant concerns for oil industries during production, transportation, and storage. This study aims to investigate the degelation behavior of waxy oil and simulate the flow restart process using numerical simulations. The results show that the degelation temperature is higher than the gelation temperature, leading to thermal hysteresis. Heating the gelled oil to the degelation temperature instead of the wax disappearance temperature can save excessive heating energy during storage and transport operations.
Article
Chemistry, Multidisciplinary
Pedro Manuel Garcia Eijo, Juan Martin Cabaleiro, Guillermo Artana
Summary: This article considers rectangular microchannels made of glass and thin polymeric walls with different roughness, and investigates how the aspect ratio of the microchannel affects the fluid motion during the initial viscous regimes. A model is proposed based on effective static contact angle and friction coefficient, and experimental investigation is conducted to obtain these coefficients for different aspect ratios. The results show that for low aspect ratios, the effective contact angle is smaller while the effective friction coefficient is larger. Rough surfaces lead to pinning and depinning events that significantly reduce the effective static contact angle.
Article
Engineering, Mechanical
Busra Duran, Jerome Cavoret, David Philippon, Fabrice Ville, Arnaud Ruellan, Frank Berens
Summary: This study analyzes the changes in the physicochemical properties and tribological performances of gear transmission oils during field operation, finding differences from traditional engine oils.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
Baocheng Liu, Hongsheng Chen, Jun Zhou, Jing Wang, Wenxian Wang, Xiaochun Chen, Sanxiao Xi
Summary: This study used fast hot pressing sintering to fabricate WC/AlCoCrFeNi2.1 metal matrix composites (MMCs). It was found that the addition of reinforced particles increased the microhardness, nanoindentation and wear resistance of the MMCs. During frictional processes, an oxide film formed, providing material protection, enhancing stability and reducing friction-induced losses.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
Pradip Kumar Verma, Alok Singh
Summary: This study investigates the mechanical properties and wear resistance of CoMoMnNiV high entropy alloy reinforced aluminium matrix composite processed through stir-squeeze casting assisted with an ultrasonic transducer. The results show significant improvements in mechanical properties and wear resistance, with the composite containing 8 wt% HEA demonstrating the highest resistance to wear. Optical microscopy, SEM, and an optical profilometer were used for a thorough examination of the microstructure and worn surface.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
Zhenghai Yang, Yingjian Song, Jinlong Jiao, Wenbo Li, Bao Shangguan, Yongzhen Zhang
Summary: This study investigated the friction, wear properties, and current-carrying properties of copper-graphite composites paired with brass C28000. The results showed that the current-carrying properties of the composite materials were excellent, but their wear rate was the main limiting factor. Furthermore, an increase in the thickness of the graphite layer led to an improvement in the uniformity of damage.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
Moustafa Mahmoud Yousry Zaghloul, Karen Steel, Martin Veidt, Michael T. Heitzmann
Summary: This research evaluates and compares the impact of different material types on the tribological characteristics of Polyamide 6 composites, and finds that glass fiber-reinforced Polyamide 6 exhibits better friction and wear performance under high-pressure velocity factors.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
Shaoqing Qin, Lida Zhu
Summary: In this paper, the surface and subsurface damage of laser assisted grinding CrCoNi medium entropy alloys were investigated using molecular dynamics simulations. The results showed that the application of laser energy can reduce cutting forces and minimize subsurface damage.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
Kaikui Zheng, Youxi Lin, Tingzheng Lai, Chenghui Gao, Ming Liu, Zhiying Ren
Summary: The study investigated the use of waste foundry resin-bonded sand as a substitute for copper in resin-based brake material. It found that the waste sand was more favorable for improving the overall friction and wear properties of the material compared to copper. Waste sand benefited the material by forming a friction layer, leading to increased friction coefficient and stability. Brake material with 10-15% waste sand showed excellent heat-fade resistance.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
Dayang Li, Fanhao Zhou, Yutong Gao, Kun Yang, Huimin Gao
Summary: This article introduces a continuous prediction model based on deep learning for predicting the power output of steam turbines. The model uses long short term memory (LSTM) method to develop a trend prediction model and optimizes the prediction model through feature selection method. Experimental results show that the model outperforms other models in terms of prediction performance.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
Tomohiro Toyoda, Ryo Yasuike, Toshihiro Noda
Summary: In this study, a elasto-plastic constitutive model of friction incorporating the concept of superloading surface was developed based on the subloading friction model. The proposed model achieves a smooth transition of friction by describing the evolution rule of structure, treating the state with static friction coefficient larger than kinetic friction coefficient as the bulkiness of structure. The positive definiteness of the plastic multiplier, loading condition, and material parameters were derived, and the validity of the proposed model in accordance with the subloading-friction model was confirmed through a stick-slip simulation of a mass-spring system.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
P. Balaji, B. Surya Rajan, K. Sathickbasha, P. Baskara Sethupathi, Deviga Magadevan
Summary: This study emphasizes the importance of using a variety of solid lubricants with different oxidation temperature regimes to enhance the tribological performance of brake pads.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
Jian Ma, Yancong Liu, Javad Mostaghimi, Na Zhang
Summary: This paper investigates the influence of preparation strategies on the lubrication properties of surface textures. Three laser scanning strategies are proposed to achieve a sinusoidal textured surface, and the evolution of surface structure and chemical composition is discussed. The findings show that ridge structures enhance anti-wear properties but also increase the friction coefficient. However, the oil cover preparation method prevents the formation of ridges and improves wettability.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
Mohammad Roostaei, Arvin Taghizadeh Tabrizi, Hossein Aghajani
Summary: In this research, the Al2O3/MoS2 nanocomposite coating layer was successfully applied on the surface of Ti-6Al-4 V alloy. The relation between the surface characteristics and wear resistance of the coating was studied using atomic force microscopy analysis and pin-on-disk wear test method. The results showed that the nanocomposite coating significantly reduced the wear rate and provided an equation to calculate the Lancaster coefficient.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
Musa Bilgin, Sener Karabulut, Halil Karakoc, Yunus Kayir, Murat Sarikaya
Summary: This study investigates various methods to improve the machinability efficiency of Inconel 718 alloy while considering their effect on microstructural properties. The results show that hot+PMQL, hot+SiCNMQL, and hot+Al2O3-NMQL contribute significantly to the improvement of machinability characteristics. The EBSD analysis also reveals that a limited area is affected by heat in the hot machining environment and that the removal of the heated layer during milling process helps preserve the microstructure.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
Q. Gao, Y. Fan, Y. G. Wu, J. L. Liu, J. Wang, L. Li
Summary: Fretting wear significantly affects the hysteresis behavior of the contact surface and leads to joint degradation. This study investigates the influence of harmonic normal force on the evolution of interface morphology and contact parameters with fretting wear. The results show that the harmonic normal force can significantly influence the hysteresis loop and the energy dissipation distribution on the contact surface.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
Benjamin Weiland, Floriane Leclinche, Anis Kaci, Brigitte Camillieri, Betty Lemaire-Semail, Marie -Ange Bueno
Summary: This study presents a systematic approach to generating control signals for a tactile simulator that simulate the touch of textile fabrics. By using a friction modulation tactile surface and acquiring forces from real surfaces with artificial finger mimicking fingerprints, control signals are generated and processed in the frequency domain before sending them to the tactile stimulator. The study focuses on the potential benefits of incorporating fingerprint information in fabric simulations to achieve a more realistic tactile perception. A sensory analysis with 36 participants using the generated control signals showed better discrimination without fingerprint information.
TRIBOLOGY INTERNATIONAL
(2024)