Zhuo Chen^1,*, Ningning Wang², Wenbo Jin³, Dui Li¹

Energy Engineering, Vol.121, No.4, pp. 1007-1026, 2024, DOI:10.32604/ee.2023.045270 - 26 March 2024

Abstract A hard problem that hinders the movement of waxy crude oil is wax deposition in oil pipelines. To ensure the safe operation of crude oil pipelines, an accurate model must be developed to predict the rate of wax deposition in crude oil pipelines. Aiming at the shortcomings of the ENN prediction model, which easily falls into the local minimum value and weak generalization ability in the implementation process, an optimized ENN prediction model based on the IRSA is proposed. The validity of the new model was confirmed by the accurate prediction of two sets of… More > Graphic Abstract

Ruiqiong Wang¹, Tiantian Du², Jinchen Cao^2,*, Guoqiang Wang³

Frontiers in Heat and Mass Transfer, Vol.22, No.1, pp. 129-139, 2024, DOI:10.32604/fhmt.2024.047825 - 21 March 2024

Abstract With the advancement of oilfield extraction technology, since oil-water emulsions in waxy crude oil are prone to be deposited on the pipe wall, increasing the difficulty of crude oil extraction. In this paper, the mesoscopic dissipative particle dynamics method is used to study the mechanism of the crystallization and deposition adsorbed on the wall. The results show that in the absence of water molecules, the paraffin molecules near the substrate are deposited on the metallic surface with a horizontal morphology, while the paraffin molecules close to the fluid side are arranged in a vertical column More >

Majid Ahmed Mohammed¹, Abdullah Talab Derea², Mohammed Yaseen Lafta³, Obed Majeed Ali¹, Omar Rafae Alomar^4,*

Frontiers in Heat and Mass Transfer, Vol.21, pp. 215-226, 2023, DOI:10.32604/fhmt.2023.041668 - 30 November 2023

Abstract It is common knowledge that phase-change materials are used for the purpose of thermal storage because of the characteristics that are exclusive to these materials and not found in others. These characteristics include a large capacity for absorbing heat and a large capacity for releasing heat when the phase changes; however, these materials have a low thermal conductivity. This paper presents the results of an experimental study that investigated the impact that nanoparticles of copper oxide had on reducing the temperature of solar panels. The phase change substance that was used was determined to be More >

Xincan Song^1,3,4, Lin Wang^1,3,4,*, Cheng Yu^1,2, Jiaxin Chen^1,3,4, Linjie Ma^1,3,4

Energy Engineering, Vol.120, No.8, pp. 1837-1852, 2023, DOI:10.32604/ee.2023.027637 - 05 June 2023

Abstract The coupled formation of wax crystals and hydrates is a critical issue for the safety of deep-sea oil and gas exploration and subsea transport pipeline flow. Therefore, this paper conducts an experimental study on the characteristics of methane hydrate formation in a water-in-oil (W/O) system with different wax crystal contents and explores the influence of different initial experimental pressures on the induction period and maximum rate of hydrate formation. The wavelet function was introduced to process the reaction rate and calculate the maximum speed of hydrate formation. Notably, the higher the pressure, the smaller the… More >

N. Poyyamozhi^a,* , A. Karthikeyan^b

Frontiers in Heat and Mass Transfer, Vol.18, pp. 1-6, 2022, DOI:10.5098/hmt.18.13

Abstract This research focuses on the development of solar ponds for efficient storage of solar energy. The influence of phase change material in the solar storage capability of solar ponds has been studied in the present wok. A comparison in the temperature fluctuations of a typical solar pond is made with its counterpart provided with phase change material. Readings have been taken during the sunshine hours in a day, and extended to seventy-five days. The solar pond exhibited identical fluctuations in average temperature irrespective of the presence of phase change material. The results revealed that during… More >

Rongge Xiao^a,* , Qi Zhuang^a, Shuaishuai Jin^a , Wenbo Jin^a

Frontiers in Heat and Mass Transfer, Vol.18, pp. 1-7, 2022, DOI:10.5098/hmt.18.8

Abstract A model for predicting wax deposition rate in pipeline transportation is constructed to predict wax deposition in actual pipeline, which can provide decision support for the flow guarantee of waxy crude oil in pipeline transportation. This paper analyzes the working principle of Back Propagation Neural Networks (BPNN). Aiming at the problems of BPNN model, such as over learning, long training time, low generalization ability and easy to fall into local minimum, the paper proposes an improved scheme of using Whale Optimization Algorithm (WOA) to optimize BPNN model(WOABPNN).Taking 38 groups of crude oil wax deposition experimental More >

Qi Zhuang^a,* , Zhuo Chen^b, Dong Liu^c, Yangyang Tian^d

Frontiers in Heat and Mass Transfer, Vol.19, pp. 1-8, 2022, DOI:10.5098/hmt.19.19

Abstract In order to improve the accuracy and efficiency of wax deposition rate prediction of waxy crude oil in pipeline transportation, A GRA-IPSO-ELM model was established to predict wax deposition rate. Using Grey Relational Analysis (GRA) to calculate the correlation degree between various factors and wax deposition rate, determine the input variables of the prediction model, and establish the Extreme Learning Machine (ELM) prediction model, improved particle swarm optimization (IPSO) is used to optimize the parameters of ELM model. Taking the experimental data of wax deposition in Huachi operation area as an example, the prediction performance More >

Ilushin Pavel, Vyatkin Kirill, Anton Kozlov^*

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.5, pp. 1229-1241, 2022, DOI:10.32604/fdmp.2022.020424 - 27 May 2022

Abstract When producing hydrocarbons, an important task relates to the optimization of the stock of the producing well. The main complications for wells in non-working mode are represented by the formation of asphalt-resin-paraffin deposits. This issue is one of the most common problems in the production and transportation of oil. A promising method to deal with these deposits is the application of smooth coatings made of epoxy polymers on the inner surface of the production well tubing. In this work, a number of laboratory studies were carried out on the “Cold Finger” installation to assess the More > Graphic Abstract

Zunaira Sher¹, Muhammad Umair Majid¹, Sameera Hassan¹, Fatima Batool¹, Beenish Aftab^1,2, Bushra Rashid^1,*

Phyton-International Journal of Experimental Botany, Vol.90, No.6, pp. 1613-1632, 2021, DOI:10.32604/phyton.2021.016154 - 28 June 2021

Abstract Pakistan is facing the threat of Cotton Leaf Curl Virus (CLCuV) which is transmitted through whitefly to cotton crop. Molecular mechanism of leaf epicuticular wax protects the plants from different pathogens including insect attack and disease transmission. Objective of current study is the isolation and characterization of a wax related gene GaCyPI from Gossypium arboreum under CLCuV infection. A fragment of 475 bp was isolated from the total RNA and 3’ and 5’ RACE-PCR products were arranged by overlapping the extended sequences at both the ends. Deduced protein sequence of GaCyPI showed homology with Cyclophilin cis-trans isomerase… More >

Dafni Foti¹, Costas Passialis¹, Elias Voulgaridis¹, Stergios Adamopoulos^2,*

Journal of Renewable Materials, Vol.9, No.1, pp. 85-96, 2021, DOI:10.32604/jrm.2021.011868 - 30 November 2020

Abstract Recycled polystyrene in combination with paraffin wax, alkyd resin, and gum rosin were used as components in formulations to investigate their water repellency when applied to cellulosic filter paper substrates. Polystyrene was used in concentration of 5, 10, 15 and 20%, alkyd resin and gum rosin of 5% each and paraffin wax of 0.5%. Totally, twenty four water repellent solutions were prepared. Water repellency was evaluated in terms of water absorption of the cellulosic fibrous mats. The relations between retention of solid substances of the formulations and grammage and water absorption of filter paper samples… More >