Weiting Jiang^*, Tingni He^*, Chongyang Wang, Weiguo Pan, Jiang Liu

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.6, pp. 1447-1461, 2023, DOI:10.32604/fdmp.2023.025269 - 30 January 2023

Abstract Computational Fluid Dynamics (CFD) is used here to reduce pressure loss and improve heat exchange efficiency in the recuperator associated with a gas turbine. First, numerical simulations of the high-temperature and low-temperature channels are performed and, the calculated results are compared with experimental data (to verify the reliability of the numerical method). Second, the flow field structure of the low-temperature side channel is critically analyzed, leading to the conclusion that the flow velocity distribution in the low-temperature side channel is uneven, and its resistance is significantly higher than that in the high-temperature side. Therefore, five More > Graphic Abstract

Javed S. Shaikh^1,*, Krishna Kumar¹, Khizar A. Pathan², Sher A. Khan³

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.6, pp. 1637-1653, 2023, DOI:10.32604/fdmp.2023.025113 - 30 January 2023

Abstract The complex fluid-dynamic instabilities and shock waves occurring along the surface of a two-dimensional wedge at high values of the Mach number are studied here through numerical solution of the governing equations. Moreover, a regression model is implemented to determine the pressure distribution for various Mach numbers and angles of incidence. The Mach number spans the interval from 1.5 to 12. The wedge angles (θ) are from 5° to 25°. The pressure ratio (P₂/P₁) is reported at various locations (x/L) along the 2D wedge. The results of the numerical simulations are compared with the regression model More >

Wei Chen^1,*, Ao Xu¹, Hejun Zhang¹, Mingquan Sheng¹, Yue Liang¹, Frederic Skoczylas²

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.6, pp. 1623-1636, 2023, DOI:10.32604/fdmp.2023.025083 - 30 January 2023

Abstract Two different freeze-thaw cycles (FTC) are considered in this study to assess the related impact on gas permeability and micro-pore structure of a mortar. These are the water-freezing/water-thawing (WF-WT) and the air-freezing/air-thawing (AF-AT) cycles. The problem is addressed experimentally through an advanced nuclear magnetic resonance (NMR) technique able to provide meaningful information on the relationships among gas permeability, pore structure, mechanical properties, and the number of cycles. It is shown that the mortar gas permeability increases with the number of FTCs, the increase factor being 20 and 12.83 after 40 cycles for the WF-WT and More >

Liang Yang^*, Tianle Xi, Zhixing Wang

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.6, pp. 1585-1608, 2023, DOI:10.32604/fdmp.2023.024987 - 30 January 2023

Abstract The VOF method is used to simulate the dynamics of a droplet interacting with a structure consisting of an array of microcolumns mounted on a flat surface. Such a specific configuration is intended to mimic the typical properties of lotus leaves, which typically display regularly arranged micron-scale papillary structures. After setting the initial velocity of the simulated droplet on the basis of practical considerations, an analysis is conducted about the effect of the characteristic size of the microstructure on the apparent contact angle. The pressure variation in the microstructure caves is also examined. The simulation More >

Yuxing Yang, Peng Zhang^*, Meng Lv

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.6, pp. 1397-1409, 2023, DOI:10.32604/fdmp.2023.024916 - 30 January 2023

Abstract The performances of turbine blades have a significant impact on the energy conversion efficiency of vertical solar power plants. In the present study, such a relationship is assessed by considering two kinds of airfoil blades, designed by using the Wilson theory. In particular, numerical simulations are conducted using the SST K − ω model and assuming a wind speed of 3–6 m/s and seven or eight blades. The two airfoils are the NACA63121 (with a larger chord length) and the AMES63212; It is shown that the torsion angle of the former is smaller, and its wind drag More > Graphic Abstract

Xing Deng^1,2, Feipeng Da^1,*, Haijian Shao^2,3

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.6, pp. 1369-1383, 2023, DOI:10.32604/fdmp.2023.024836 - 30 January 2023

Abstract This study employs nine distinct deep learning models to categorize 12,444 blood cell images and automatically extract from them relevant information with an accuracy that is beyond that achievable with traditional techniques. The work is intended to improve current methods for the assessment of human health through measurement of the distribution of four types of blood cells, namely, eosinophils, neutrophils, monocytes, and lymphocytes, known for their relationship with human body damage, inflammatory regions, and organ illnesses, in particular, and with the health of the immune system and other hazards, such as cardiovascular disease or infections, More > Graphic Abstract

Zhong Chen^1,2,*, Yalin Wang^1,2, Yue Li²

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.6, pp. 1349-1367, 2023, DOI:10.32604/fdmp.2023.024513 - 30 January 2023

Abstract In order to improve the efficiency as well the adaptability and operability of traditional devices used to dredge drainage pipelines a new design is presented here, obtained by matching the structural specifications of a drainage pipeline with the working principle of a high-pressure water jet (HPWJ). To effectively improve the water jet nozzle performances, the nozzle’s structural parameters of the proposed device have been analyzed through Computational fluid dynamics (CFD) simulation. The corresponding behavior of the fluids inside and outside the self-rotational nozzle has been numerically simulated. The final design for the nozzle has been More > Graphic Abstract

Hongzhi Liu¹, Shasha Wu¹, Yongjun Zhang^2,*, Tongxu Hu²

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.6, pp. 1551-1572, 2023, DOI:10.32604/fdmp.2023.024430 - 30 January 2023

Abstract The internal temperature of cast-in-place concrete bridges undergoes strong variations during the construction as a result of environmental factors. In order to determine precisely such variations, the present study relies on the finite element method, used to model the bridge box girder section and simulate the internal temperature distribution during construction. The numerical results display good agreement with measured temperature values. It is shown that when the external temperature is higher, and the internal and external temperature difference is relatively small, the deviation of the fitting line from existing specifications (Chinese specification, American specification, New More >

Feiran Lv¹, Min Wang², Chuntian Zhe¹, Chang Guo³, Ming Gao^1,*

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.6, pp. 1463-1478, 2023, DOI:10.32604/fdmp.2023.024259 - 30 January 2023

Abstract The so-called T-shaped reducing tees are typically used to divide, change and control (to a certain extent) the flow direction in pipe networks. In this study, the Ffowcs Williams–Hawkings (FW-H) equation and the Large Eddy Simulation (LES) methods are used to simulate the flow-induced noise related to T-shaped reducing tees under different inlet flow velocities and for different pipe diameter ratios. The results show that the maximum flow velocity, average flow velocity, and vorticity in the branch pipe increase gradually as the related diameter decreases. Strong vorticity and secondary flows are also observed in the More > Graphic Abstract

Zhao Yu^1,2,*

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.6, pp. 1521-1534, 2023, DOI:10.32604/fdmp.2023.023296 - 30 January 2023

Abstract Oil saturation is a critical parameter when designing oil field development plans. This study focuses on the change of oil saturation during water flooding. Particularly, a meter-level artificial model is used to conduct relevant experiments on the basis of similarity principles and taking into account the layer geological characteristics of the reservoir. The displacement experiment’s total recovery rate is 41.35%. The changes in the remaining oil saturation at a millimeter-scale are examined using medical spiral computer tomography principles. In all experimental stages, regions exists where the oil saturation decline is more than 10.0%. The shrinkage More >