Guowei Zhu^*, Kangliang Guo, Haoran Yang, Xinchen Gao, Shuangshuang Zhang

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.5, pp. 1521-1528, 2022, DOI:10.32604/fdmp.2022.020942

Abstract In order to overcome the typical limitations of numerical simulation methods used to estimate the production of low-permeability reservoirs, in this study, a new data-driven approach is proposed for the case of water-driven hypo-permeable reservoirs. In particular, given the bottlenecks of traditional recurrent neural networks in handling time series data, a neural network with long and short-term memory is used for such a purpose. This method can reduce the time required to solve a large number of partial differential equations. As such, it can therefore significantly improve the efficiency in predicting the needed production performances. Practical examples about water-driven hypotonic… More >

Fei Zhou, Yu Zhou^*, Xuemin Ye

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.4, pp. 1025-1037, 2022, DOI:10.32604/fdmp.2022.020196

Abstract Taking a two-stage variable-pitch axial fan as the research object, five schemes, including a single counter-flow rib layout grooved tip, are numerically simulated using the fluent software. The results indicate that, compared with the original blade tip, the total pressure rise and efficiency of the four proposed schemes have been improved to various degrees, with Scheme 4 (groove tip with double counterflow ribs) displaying the best performances. The total pressure and efficiency are increased by 113.44 Pa and 0.955%, respectively. The blade tip leakage flow is reduced to varying degrees under different schemes, according to the following order: Scheme 1, Scheme… More >

Hexing Liu¹, Yi Huang¹, Jinlong Zheng¹, Ye Tian¹, Mengran Xu^2,*, Huajie Liu²

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.4, pp. 999-1013, 2022, DOI:10.32604/fdmp.2022.020059

Abstract The application of polycarboxylic acid as a fluid loss additive for cement (i.e., a substance specifically designed to lower the volume of filtrate that passes through the cement) can prolong the thickening time of cement slurries. Given the lack of data about the effects of carboxylic acid monomers as possible components for the additives traditionally used for oil-well cement, in this study different cases are experimentally investigated considering different types of these substances, concentrations, temperatures, and magnesium ion contamination. The results demonstrate that itaconic acid has a strong retarding side effect, while maleic and acrylic acids have similar influences on… More >

Changlin Wang^1,2,*, Yu Tang², Xiao Shen³, Wenjing Sun², Guanyong Li²

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.4, pp. 919-932, 2022, DOI:10.32604/fdmp.2022.019036

Abstract This study proposes three possible keel-surface layer combinations to implement a new type of thermally insulating decorative wall system. A set of 8 samples has been studied. In particular, through theoretical calculations, simulations, and experimental verification, the influence of different types of connecting structures on the overall thermal performance of the wall system has been determined. It has been found that a proper combination of these elements can meet existing energy-saving standards and effectively reduce the energy loss caused by thermal bridges due to the installation of steel keels at the edges of integrated wall panels. More >

Daqin Zhang^1,2, Chufeng Yang³, Huayang Ran^1,2, Juanli Wang^1,2,*, Jintao Wan^1,2,*, Yuhu Li^1,2, Pujun Jin^1,2, Daodao Hu^1,2

Journal of Renewable Materials, Vol.10, No.7, pp. 1797-1811, 2022, DOI:10.32604/jrm.2022.018754

Abstract The development of efficient green flame retardants is an important way to realize more sustainable epoxy thermosets and downstream materials. In this work, a monoepoxide is synthesized through O-glycidylation of eugenol, and then reacted with DOPO (9,10-dihydro-9-oxa-10-phosphophenanthrene-10-oxide) to obtain a new bio-based flame retardant, DOPO-GE. DOPO-GE is blended with a bisphenol A epoxy prepolymer exhibiting good compatibility and DDS (4,4′-diaminodiphenylsulfone) is used as the curing agent to afford epoxy thermosets. Although DOPO-GE leads to the reduced glass transition temperature of the thermosets, the storage modulus increases considerably. The DOPO-GE-modified thermosets exhibit the high thermal stability with the onset thermal decomposition… More >

Wei Chen^1,2, Zhaofeng Guo^3,4,*, Hongda Feng^3,4, Sheng Hu^1,2, Ling Lu^1,2, Chuanmin Chen^3,4, Xiaowen Wu^1,2, Hao Cao^1,2

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.2, pp. 481-496, 2022, DOI:10.32604/fdmp.2022.015746

Abstract This study investigates a dual-cavity resonant composite sound-absorbing structure based on a micro-perforated plate. Using the COMSOL impedance tube model, the effects of various structural parameters on sound absorption and sound insulation performances are analyzed. Results show that the aperture of the micro-perforated plate has the greatest influence on the sound absorption coefficient; the smaller the aperture, the greater is this coefficient. The thickness of the resonance plate has the most significant influence on the sound insulation and resonance frequency; the greater the thickness, the wider the frequency domain in which sound insulation is obtained. In addition, the effect of… More >

Jin Yang^1,2, Wen Liang¹, Xingyang He^1,2,*, Ying Su^1,2, Fulong Wang¹, Tie Wang¹, Jianxiang Huang¹

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.1, pp. 15-27, 2022, DOI:10.32604/fdmp.2022.018135

Abstract A solution polymerization method has been used to synthesize a polyacrylic-type superabsorbent polymer (SAP). The influence of various influential factors, such as the temperature, neutralization degree, cross-linking agent, and initiator, on the water absorption capacity of SAP has been investigated. The results show that the absorption can display a non-monotonic behavior depending on the synthesis conditions. The absorption can also change according to the pH, ion types and ion concentration. As the pH value increases, the water absorption capacity decreases significantly. It also decreases if the Na⁺ concentration becomes higher and becomes particularly low in solutions containing Mg²⁺. With the… More >

Xiaorui Cheng^1,2,*, Xiang Liu¹, Boru Lv¹

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.1, pp. 93-107, 2022, DOI:10.32604/fdmp.2022.017566

Abstract An AP1000 nuclear reactor coolant pump is considered to assess the influence of the Impeller/Guide vane clearance on the performances of this type of pumps. Experiments and numerical simulations relying on an unidirectional fluid-solid coupling approach are used to investigate the problem (stress, strain and mode of the rotor). The results reveal the relationship existing between the hydraulic performance of the nuclear reactor coolant pump and the clearance ratio. The effect of clearance ratio on the maximum equivalent stress on the back surface of the impeller blade is greater than that on the working surface (the maximum equivalent stress on… More >

Weiwei Duan^*, Lingfeng Tang

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.6, pp. 1143-1164, 2021, DOI:10.32604/fdmp.2021.016692

Abstract Vertical infusion (self-emptying) bags used for Intravenous infusion are typically obtained by moulding a soft envelope of polypropylene. In normal conditions a continuous flow of liquid can be obtained with no need to use a pump. In the present study, the relationship between air pressure effects and the drug drip rate have been investigated experimentally and numerically. After determining relevant experimental data about the descending height of liquid level, the dropping speed and pressure, the ordinary least square method and MATLAB have been used to reconstruct the related variation and interrelation laws. Numerical simulations have been performed to determine the… More >

Yongheng Ku¹, Jinguang Zhang^2,3, Zhenyu Wang^3,4, Youxin Li^3,5, Haowei Yao^3,5,*

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.6, pp. 1077-1090, 2021, DOI:10.32604/fdmp.2021.015779

Abstract In order to study the extinguishing performance of high-pressure-water-mist-based systems on the fires originating from power transformers the PyroSim software is used. Different particle velocities and flow rates are considered. The evolution laws of temperature around transformer, flue gas concentration and upper layer temperature of flue gas are analyzed under different boundary conditions. It is shown that the higher the particle velocity is, the lower the smoke concentration is, the better the cooling effect on the upper layer temperature of flue gas layer is, the larger the flow rate is and the better the cooling effect is. More >