Zhibin Zhang^1,2, Yongjun Gong^1,*, Liping Zhang³, Min Xv², Gaofeng Shang⁴

FDMP-Fluid Dynamics & Materials Processing, Vol., , DOI:10.32604/fdmp.2022.019746

Abstract The effects of oblique submerged scouring jets on sand beds with various particle sizes have been studied experimentally. In particular, a total of 25 experiments have been carried out to explore the influences of the jet angle and application time on the considered submerged sand beds. Test results conducted with a specially-designed device have shown that the scouring efficiency attains a maximum when the inclination angle is in the range between 15° and 20° and then it decreases when the inclination angle becomes higher. More >

M. K. Shilpa¹, Md Abdul Raheman², Abdul Aabid^3,*, Muneer Baig³, R. K. Veeresha⁴, Nagesh Kudva⁴

FDMP-Fluid Dynamics & Materials Processing, Vol., , DOI:10.32604/fdmp.2022.020351

Abstract Conventional refrigeration processes release ammonia and freon into the atmosphere, which results in global warming. These problems may be overcome by using thermoelectric modules because of the absence of coolants or refrigerants in these systems. However, the cooling performances of such modules are relatively small in comparison to those of conventional refrigerators. In this paper, the working principles of thermoelectric modules are discussed together with a review of different relevant aspects, namely: the thermoelectric materials, and their mechanical properties used to build thermoelectric devices, different types of thermoelectric devices available on the market, mathematical modeling of thermoelectric materials, and various… More >

Yassmine Rghif^1,*, Belkacem Zeghmati², Fatima Bahraoui¹

FDMP-Fluid Dynamics & Materials Processing, Vol., , DOI:10.32604/fdmp.2022.021500

Abstract Revise the abstract as follows: This work aims to investigate numerically the influence of the buoyancy ratio and the Dufour parameter on thermosolutal convection in a square Salt Gradient Solar Pond (SGSP). The absorption of solar radiation by the saline water, the heat losses and the wind effects via the SGSP free surface are considered. The mathematical model is based on the Navier-Stokes equations used in synergy with the thermal energy equation. These equations are solved using the finite volume method and the Gauss algorithm. Velocity-pressure coupling is implemented through the SIMPLE algorithm. Simulations of the SGSP are performed for… More >

Ting Zhang¹, Denghao Wu^1,2,*, Shijun Qiu², Peijian Zhou¹, Yun Ren³, Jiegang Mou¹

FDMP-Fluid Dynamics & Materials Processing, Vol., , DOI:10.32604/fdmp.2022.019617

Abstract Stall phenomena increase the complexity of the internal flow in centrifugal pump impellers. In order to tackle this problem, in the present work, a large eddy simulation (LES) approach is applied to determine the characteristics of these unstable flows. Moreover, a vorticity identification method is used to characterize quantitatively the vortex’s position inside the impeller and its influencing area. By comparing the outcomes of the numerical simulations and experimental results provided by a Particle Image Velocimetry (PIV) technique, it is shown that an apparent “alternating stall” phenomenon exists inside the impeller when relatively small flow rate conditions are considered. The… More >

Dongxia Wu¹, Mourad Rahim¹, Wendong Li¹, Mohammed El Ganaoui^1,*, Rachid Bennacer²

FDMP-Fluid Dynamics & Materials Processing, Vol., , DOI:10.32604/fdmp.2022.021917

Abstract Phase Change Materials (PCMs) have high thermal inertia, and hemp concrete (HC), a bio-based concrete, has strong hygroscopic behavior. In previous studies, PCM has been extensively combined with many materials, however, most of these studies focused on thermal properties and neglected hygroscopic properties. In this paper, the two materials were combined as a building envelope and the hygrothermal properties were studied simultaneously. To explore the feasibility of the combined material, numerical studies were performed to investigate the temperature and relative humidity behavior inside the HC, and the effect of adding PCM on the hygrothermal behavior of the HC. The results… More >

Yong Wang, Hongjian Ni^*, Ruihe Wang, Shubin Liu

FDMP-Fluid Dynamics & Materials Processing, Vol., , DOI:10.32604/fdmp.2022.020405

Abstract A specific model is elaborated for stick-slip and bit-bounce vibrations, which are dangerous dynamic phenomena typically encountered in the context of rotary drilling applications. Such a model takes into account two coupled degrees of freedom of drill-string vibrations. Moreover, it assumes a state-dependent time delay and a viscous damping for both the axial and torsional vibrations and relies on a sawtooth function to account for the cutting force fluctuation. In the frame of this theoretical approach, the influence of rock brittleness on the stability of the drill string is calculated via direct integration of the model equations. The results show… More >

Kunhong Lv, Zhiqiang Huang^*, Xingjie Ling, Xueqin Xia

FDMP-Fluid Dynamics & Materials Processing, Vol., , DOI: 10.32604/fdmp.2022.020294

Abstract The weight loss of cement slurry is the main cause of early annular air channeling and accurate experimental evaluation of the law of loss change is the key to achieve compression stability and prevent this undesired phenomenon. Typically, tests on the pressure loss of cement slurry are carried out for temperature smaller than 120°C, and this condition cannot simulate effectively the situation occurring in high temperature wells. For this reason, in this study a series of experimental tests have been conducted considering a larger range of temperatures, different retarders and fluid loss additives. The results show that with an increase… More >

Baris Burak Kanbur, Sheng Quan Heng, Fei Duan^*

FDMP-Fluid Dynamics & Materials Processing, Vol., , DOI:10.32604/fdmp.2022.021793

Abstract Steady-state hydrodynamic patterns of ethanol droplet train impingement on the heated aluminum surface is investigated in the surface temperature range of 80°C–260°C using two different Weber numbers (We) of 618 and 792. Instead of a vertical train impingement, the droplet train is sent to the aluminum surface with an incline of 63 degrees. Changes in the spreading length are observed at different surface temperatures for two different We values, which are obtained by using two different pinholes with 100 and 150 μm diameters. The greatest spreading length is seen at the lowest surface temperature (80°C) and it continuously decreases until… More >

Baris Burak Kanbur, Sheng Quan Heng, Fei Duan^*

FDMP-Fluid Dynamics & Materials Processing, Vol., , DOI: 10.32604/fdmp.2022.021792

Abstract The present study investigates thermal gradients on the heated aluminum and glass surfaces during ethanol droplet train impingement in the surface temperature ranges of 140°C–240°C. The ethanol droplet impingement is applied with an incline of 63 degrees and the droplet diameter is 0.2 mm in both aluminum and glass surface experiments. Thermal gradients are observed with a thermographic camera. Compared to the glass, the aluminum surface has very small liquid accumulations and better evaporation performance thanks to its higher thermal conductivity. Low thermal conductivity of glass results in higher thermal gradients on the surface. The droplet impact area on the… More >

Chenyang Shi^1,2,3, Fankun Meng^1,2,3,*, Hongyou Zhang⁴, HuiJiang Chang⁴, Xun Zhong^1,2,3, Jie Gong^1,2,3, Fengling Li⁵

FDMP-Fluid Dynamics & Materials Processing, Vol., , DOI:10.32604/fdmp.2022.019788

Abstract As current calculation models for inter-well connectivity in oilfields can only account for vertical wells, an updated model is elaborated here that can predict the future production performance and evaluate the connectivity of horizontal wells (or horizontal and vertical wells). In this model, the injection-production system of the considered reservoir is simplified and represented with many connected units. Moreover, the horizontal well is modeled with multiple connected wells without considering the pressure loss in the horizontal direction. With this approach, the production performance for both injection and production wells can be obtained by calculating the bottom-hole flowing pressure and oil/water… More >