Long Wang¹, Qingyun Shen¹, Gui Wang^2,*

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.11, pp. 2877-2890, 2023, DOI:10.32604/fdmp.2023.029206

Abstract Drill cuttings are broken bits of solid material removed from a borehole drilled by rotary, percussion, or auger methods and brought to the surface in the drilling mud. When these cuttings enter the annulus, they have an effect on the drilling fluid rheology and density, which is, in general, quite difficult to evaluate. By introducing an empirical correlation for the rheological properties of cuttings-laden drilling fluids, this study proposes a pressure-loss prediction method for an extended-reach well (ERW). After verifying the accuracy of this method, a case study is considered and a sensitivity analysis is conducted assuming a yield-power law… More >

Ralph Eismann^a,† , Robert Adams^b

Frontiers in Heat and Mass Transfer, Vol.11, pp. 1-7, 2018, DOI:10.5098/hmt.11.4

Abstract Convergence of numerical schemes for pipe network analysis requires continuous modelling of pressure losses in the transition region between laminar and turbulent regions. Several existing correlations for the friction factor of straight pipes and helical tubes are presented. Based on these correlations a new explicit correlation for helical tubes with arbitrary surface roughness is derived. The friction factor is expressed as a continuous function of the Reynolds number covering laminar, transitional, and turbulent flow regions. Potential sources of error are also discussed, including the effects of tube deformation caused by the bending process. More >

Tao Bian¹, Xin Shen², Jun Feng¹, Bing Wang^1,*

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.3, pp. 615-628, 2021, DOI:10.32604/fdmp.2021.014902

Abstract In turbomachinery, strong secondary flow can produce significant losses of total pressure near the endwall and reduce the efficiency of the considered turbomachine. In this study, splitters located at different positions with respect to the main blade have been used to reduce such losses and improve the efficiency of the outlet guide vane (OGV). Three different relative positions have been considered assuming a NACA 65-010 profile for both the main blade and the splitter. The numerical results indicate that splitters can effectively reduce the total pressure loss by suppressing the secondary flow around the main blade, but the splitters themselves… More >

Yukun Lv, Jiaxi Yang, Jiawen Wang^*, Runcheng Zhang, Shuang Yang, Wentao Li

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.6, pp. 1203-1217, 2020, DOI:10.32604/fdmp.2020.010489

Abstract Aiming at the problem that the total pressure loss of the flue of the electric precipitator of the 350 MW unit of a power plant to the inlet of the draft fan is too large, the numerical simulation software Fluent and the standard k-ε model was used to simulate the flue, the results show that the main part of the flue mean total pressure loss is derived from the confluence header and elbow. In order to reduce the loss and consider the cost of transformation, the concept of twodimensional feature surface is established, gradually proposed three sets of flue transformation… More >

Chengwen Liu^1,*, Lin Zhu¹, Xingru Wu^2,*, Jian Liang¹, Zhaomin Li¹

CMES-Computer Modeling in Engineering & Sciences, Vol.124, No.2, pp. 561-572, 2020, DOI:10.32604/cmes.2020.010699

Abstract In drilling a deepwater well, the mud density window is narrow, which needs a precise pressure control to drill the well to its designed depth. Therefore, an accurate characterization of annular flow between the drilling riser and drilling string is critical in well control and drilling safety. Many other factors influencing the change of drilling pressure that should be but have not been studied suffi- ciently. We used numerical method to simulate the process of drill string rotation and vibration in the riser to show that the rotation and transverse vibration of drill string can increase the axial velocity in… More >

Zhiyu Guo*, Yuting Wu

The International Conference on Computational & Experimental Engineering and Sciences, Vol.22, No.3, pp. 161-164, 2019, DOI:10.32604/icces.2019.05490

Abstract Generally, the greater the difference between evaporation and condensation temperature of ORC(Organic Rankie Cycle) is, the higher system efficiency and the larger expansion ratio will be [1,2]. Fig. 1 shows that net efficiency of theoretical cycle and expansion ratio of ORC system changes with evaporation temperature when condensing temperature is 313 K (R123 and HFO-1336mzz (Z) are selected). More >

W. A. El-Askary, A. Abdel-Fattah

CMES-Computer Modeling in Engineering & Sciences, Vol.83, No.4, pp. 425-458, 2012, DOI:10.3970/cmes.2012.083.425

Abstract In the present paper, experimental and numerical studies of heat transfer and the frictional head loss of turbulent flow in a duct with a heated upper surface are performed. Four different arrangements are considered (case 1: without baffles, case 2: one perforated baffle on the upper wall and one solid baffle on the lower wall, case 3: one perforated baffle on the upper wall and one perforated baffle on the lower wall and case 4: two perforated baffles on the upper wall). A numerical code developed by the present authors is simultaneously presented including four different turbulence models; namely: the… More >

B. Madani¹, F. Topin², L. Tadrist²

FDMP-Fluid Dynamics & Materials Processing, Vol.6, No.4, pp. 351-368, 2010, DOI:10.3970/fdmp.2010.006.351

Abstract The present work deals with the hydraulic characterization of two-phase flow with phase change in a channel filled with metallic foam. We provide a general presentation of metallic foams including morphological characteristics, fabrication processes and industrial applications. The experimental facility, which consists of a hydrodynamic loop, the test section, measurement devices, and the data acquisition system, is presented. The Metallic foam sample tested in the present work is manufactured by SCPS (French manufacturer). N-pentane is used as a coolant fluid. The mass velocity values lie between 4 and 49 kg/ m2s, while the heating power in the test section ranges… More >