Surajudeen Sikiru^1,*, Hassan Soleimani², Amir Rostami¹, Mohammed Falalu Hamza^1,3, Lukmon Owolabi Afolabi⁴

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.1, pp. 31-44, 2024, DOI:10.32604/fdmp.2023.029281

Abstract Determining the adsorption of shale gas on complex surfaces remains a challenge in molecular simulation studies. Difficulties essentially stem from the need to create a realistic shale structure model in terms of mineral heterogeneity and multiplicity. Moreover, precise characterization of the competitive adsorption of hydrogen and methane in shale generally requires the experimental determination of the related adsorptive capacity. In this study, the adsorption of adsorbates, methane (CH₄), and hydrogen (H₂) on heterogeneous shale surface models of Kaolinite, Orthoclase, Muscovite, Mica, C₆₀, and Butane has been simulated in the frame of a molecular dynamic’s numerical technique. The results show that… More >

Hongqiong Zhang^1,2,#, Xu Wang^3,#, Zhaojing Qian⁴, Buchun Si^1,4,*, Kai Jin⁵, Tengfei Wang⁵

Journal of Renewable Materials, Vol.11, No.10, pp. 3647-3657, 2023, DOI:10.32604/jrm.2023.028438

Abstract Hydrochar prepared with four typical biowastes, pine wood, food waste, digested sewage sludge, and Chlorella were applied for the promotion of anaerobic digestion. The gas production and substrate composition were analyzed associated with the hydrochar characteristics. The results suggested that Chlorella hydrochar (C-C) showed the highest cumulative yield of methane (approximately 345 mL) with high total organic carbon (TOC) removal efficiency and low volatile fatty acids (VAFs) concentration. Especially, food waste hydrochar (F-C) showed a poor effect on anaerobic digestion and aroused 1.4–1.6 g/L accumulation of VAFs, in which the toxic components may account for the low efficiency. The C-C… More >

M. Arun, J. Akhil, K. Noufal, Robin Baby, Darshitha Babu, M. Jose Prakash^*

Frontiers in Heat and Mass Transfer, Vol.8, pp. 1-9, 2017, DOI:10.5098/hmt.8.23

Abstract The supercritical turbulent flow of cryogenic methane flowing in a rocket engine cooing channel is numerically analysed by imposing constant heat flux at the bottom surface of the channel. The calculation scheme is validated by comparing the results obtained with experimental results reported in literature. The heat transfer coefficient is influenced by the strong variation in thermophysical properties of methane at super critical pressure. An increasing trend in the average value of Nusselt number is observed with aspect ratio. The efficacy of both Modified Jackson and Hall and Bishop empirical correlations in predicting Nusselt number is tested for cryogenic methane… More >

M. Arun^a,*, M. Jose Prakash^b

Frontiers in Heat and Mass Transfer, Vol.11, pp. 1-10, 2018, DOI:10.5098/hmt.11.9

Abstract Prediction of heat transfer deterioration in rocket engine coolant channels with supercritical flow is essential while designing high pressure rocket engines. Three-dimensional conjugate heat transfer of cryogenic methane in rectangular engine cooling channels at supercritical pressures with asymmetric heating imposed on the bottom channel surface is numerically investigated, focusing on the effects of key parameters such as aspect ratio, heat flux and coolant pressure. Due to the similarity of the coolant channel with that of an actual rocket engine, the results obtained herein are beneficial for the design and optimization of rocket engine cooling systems. Heat flux is varied from… More >

Junjie Chen^* , Baofang Liu, Longfei Yan, Deguang Xu

Frontiers in Heat and Mass Transfer, Vol.11, pp. 1-15, 2018, DOI:10.5098/hmt.11.2

Abstract The combustion and emissions characteristics of methane-air mixtures in high-temperature catalytic micro-combustors were studied numerically. Both the heterogeneous and homogeneous chemistry were modeled simultaneously using detailed reaction mechanisms in order to better understand the role of each pathway in determining the product distributions. Computational fluid dynamics simulations were performed at a variety of pressures, temperatures, compositions, and combustor dimensions to determine their effects on the combustion and emissions characteristics. Comparisons were made between the results obtained for a purely heterogeneous case, a purely homogeneous case, and a coupled homogeneousheterogeneous case. It was shown that homogeneous and heterogeneous chemistry take place… More >

Qifen Li, Yuanbo Hou^*, Yongwen Yang, Liting Zhang, Xiaoxiao Yan

Journal of Renewable Materials, Vol.11, No.8, pp. 3333-3350, 2023, DOI:10.32604/jrm.2023.027464

Abstract Reducing CO₂ to produce methane through microbial electrolytic cell (MEC) is one of the important methods of CO₂ resource utilization. In view of the problem of low methanogenesis rate and weak CO₂ conversion rate in the reduction process, the flow field environment of the cathode chamber is changed by changing the upper gas circulation rate and the lower liquid circulation rate of the cathode chamber to explore the impact on the reactor startup and operation and products. The results showed that under certain conditions, the CO₂ consumption and methane production rate could be increased by changing the upper gas recirculation… 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

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 maximum rate of hydrate formation.… More >

Guisheng Wang^*

Energy Engineering, Vol.120, No.6, pp. 1503-1514, 2023, DOI:10.32604/ee.2023.027416

Abstract In the natural gas liquefaction process, the mixed refrigerant natural gas liquefaction process is widely used in LNG liquefaction plants because of its advantages of low energy consumption. This paper focuses on the influences of important parameters in the C3/MRC liquefaction process, that is, the comparison between propane precooling temperature and the number of moles of methane in mixed refrigerant, power consumption and loss. In addition, the total process was optimized with the optimizer and manual adjustment in HYSYS software to minimize the total power consumption. The results show that with increasing propane precooling temperature, the propane flow rate is… More >

Bing Wang^1,2,*, Zhongxun Li¹, Rui Shi¹, Yuzheng Zhang¹, Yao Yao¹

Energy Engineering, Vol.119, No.6, pp. 2469-2487, 2022, DOI:10.32604/ee.2022.021171

Abstract With policy incentives for the coalbed methane in energy industry, coalbed methane from coal production has been effectively improved by technology innovations in coalbed methane extraction and utilization. The progress of coalbed methane promotes the clean construction of energy system and contributes to carbon neutrality target. To quantitatively measure the contributions of the coalbed methane in energy industry, this paper builds a carbon emissions accounting system for coalbed methane in China and assesses the historical co-benefits of coalbed methane utilization from the aspects of emissions reduction, safety and economy. By using the parameters of gas content, raw coal production, gas… More >

Lingyun Zhao^1,2, Heng Yang^3,4,*, Yuanlong Wei^1,2,*, Yuhuan Bu^3,4, Shaorui Jing^3,4, Peiming Zhou^1,2

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.2, pp. 329-344, 2023, DOI:10.32604/fdmp.2022.020216

Abstract Perforation and fracturing are typically associated with the development of coalbed methane wells. As the cement sheath is prone to failure during this process, in this work, the effects of the casing pressure, elastic modulus of the cement, elastic modulus of the formation, and casing eccentricity on the resulting stresses are analyzed in the frame of a finite element method. Subsequently, sensitivity response curves of the cement sheath stress are plotted by normalizing all factors. The results show that the maximum circumferential stress and Mises stress of the cement sheath increase with the casing internal pressure, elastic modulus of the… More > Graphic Abstract