Impulsively generated focused jets play a significant role in various applications, including inkjet printing, needle-free drug delivery, and microfluidic devices. As the demand for generating jets and droplets from m...
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Impulsively generated focused jets play a significant role in various applications, including inkjet printing, needle-free drug delivery, and microfluidic devices. As the demand for generating jets and droplets from medium to highly viscous liquids increases, understanding the role of viscosity in jetting dynamics becomes crucial. While previous studies have examined the viscous effects on walls, the impact on free surfaces has not been thoroughly understood. This study aims to bridge this gap by integrating experiments with numerical simulations to investigate the viscous effects on focused jet formation. We demonstrate that mass and momentum transfer along the tangential direction of the free surface contribute to focused jet formation, and viscosity plays a key role in this transfer process. The viscosity-induced diffusion of the shear flow and vorticity near the free surface reduces the jet speed. Based on experimental observations and simulation results, we propose an equation to predict the viscous jet velocity. These findings offer new perspectives on viscous interface dynamics in advanced manufacturing and biomedical applications.
With the rise of blockchain as a more promising technology, industries and academia are interested to foresee a decentralized and transparent ecosystem of data storing, sharing, and verifying across platforms. The cur...
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The use of biodiesel mixtures has become a part of everyday life. The current implementation of B7 biodiesel at the pump and the premise that the near future will make B20 biodiesel compulsory leads to the necessity o...
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Nowadays, heavy metal pollution is considered one of the most important environmental issues. Thereby, this paper proposes a novel approach towards obtaining biofriendly hybrid composite beads based on sodium alginate...
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The East Japan Railway Company (hereinafter referred to as ''JR East'') is in the process o festablishing new systems for automating work through technological innovation as Japan's working-age pop...
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Radiant syngas cooler(RSC)is widely used as a waste heat recovery equipment in industrial *** this work,an RSC with radiation screens is established and the impact of gaseous radiative property models,gas components,a...
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Radiant syngas cooler(RSC)is widely used as a waste heat recovery equipment in industrial *** this work,an RSC with radiation screens is established and the impact of gaseous radiative property models,gas components,and ash particles on heat transfer is investigated by the numerical simulation *** the syngas components and the pressure environment of the RSC,a modified weighted-sum-of-gray-gases model was *** modified model shows high accuracy in *** computational fluid dynamics simulation,the calculated steam production is only 0.63%in error with the industrial *** with Smith's model,the temperature decay along the axial direction calculated by the modified model is *** components are of great significance to heat recovery capacity,especially when the absorbing gas fraction is less than 10%.After considering the influence of particles,the outlet temperature and the proportion of radiative heat transfer are less affected,but the difference in steam output reaches 2.7 t·h^(-1).The particle deposition on the wall greatly reduces the heat recovery performance of an RSC.
In this work, we have carried out research on the microstructured substrates obtained with molds made by the 3D DPL printing technique, in order to obtain a microstructured substrate with maximum displacement. Microst...
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Numerical simulations of the flow and heat transfer characteristics of four shell-and-tube molten salt electric heaters with different perforation rates was ***-and-tube electric heaters have the same geometry and tub...
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Numerical simulations of the flow and heat transfer characteristics of four shell-and-tube molten salt electric heaters with different perforation rates was ***-and-tube electric heaters have the same geometry and tube arrangement,and all of them use single segmental baffles,but there exist four different baffle openings(φ),i.e.,0%,2.52%,4.06%,and 6.31%.The results indicated that the reasonable baffle opening could significantly reduce the shell-side pressure drop,effectively decreasing the shell-side flow dead zone *** can eliminate the local high-temperature phenomenon on the surface of electric heating tubes,but the heat transfer coefficient is slightly *** perforated schemes significantly reduce shell-side pressure drop compared to the baseline solution without open *** particular,the φ=6.31% scheme exhibits the optimal performance among all the schemes,with a maximum reduction of up to 50.50% in shell-side pressure drop relative to the unopened holes *** heat transfer coefficient is the highest for φ=0%,exhibiting a range of5.26% to 5.73%,5.14% to 5.99%,and 7.31% to 8.54% higher than φ=2.52%,4.06%,and 6.31%,respectively,within the calculated *** composite index h/(Δp)^(1/3)was higher for all open-hole solutions than that for the unopened-hole *** best overall performance was for φ=6.31%,which improved the composite index by15.29%to 17.18%over the unopened-hole solution.
Pressure control in deep shale gas horizontal wells can reduce the stress sensitivity of hydraulic fractures and improve the estimated ultimate recovery(EUR).In this study,a hydraulic fracture stress sensitivity model...
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Pressure control in deep shale gas horizontal wells can reduce the stress sensitivity of hydraulic fractures and improve the estimated ultimate recovery(EUR).In this study,a hydraulic fracture stress sensitivity model is proposed to characterize the effect of pressure drop rate on fracture ***,a production prediction model is introduced accounting for a non-uniform hydraulic fracture conductivity *** results reveal that increasing the fracture conductivity leads to a rapid daily production increase in the early ***,above 0.50 D·cm,a further increase in the fracture conductivity has a limited effect on shale gas production *** initial production is lower under pressure-controlled conditions than that under *** extended pressure control durations,the cumulative production initially increases and then *** a fracture conductivity of 0.10 D·cm,the increase in production output under controlled-pressure conditions is~35%.For representative deep shale gas wells(Southern Sichuan,China),if the pressure drop rate under controlled-pressure conditions is reduced from 0.19 to 0.04 MPa/d,the EUR increase for 5 years of pressure-controlled production is 41.0 million,with an increase percentage of~29%.
The mixing and combustion processes under different reference velocities in a gas turbine combustor were numerically investigated using the Flamelet Generated Manifold(FGM)model based on the Reynolds Averaged Navier-S...
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The mixing and combustion processes under different reference velocities in a gas turbine combustor were numerically investigated using the Flamelet Generated Manifold(FGM)model based on the Reynolds Averaged Navier-Stokes(RANS)*** flow and combustion fields show strong self-similarity except on the slow auto-ignition in the mixing layer between fuel-rich product and fresh air upstream of the flame stabilization *** time-scale analysis was carried out to understand the combustion modes inside the *** general,the residence time of the fuel-mixture is much longer than both the chemical time scale and the mixing time ***,the combustion properties in each sub-zone were dominated by the mean flow ***,the combustion process exhibits a mixing-controlled feature in ***,partially premixed combustion still appears on the flame *** of the fuel was found to be oxidized in the primary zone and the intermediate zone;however,the slow oxidization reactions also play a non-negligible role on the whole combustion ***,a sketch map on the space of mixture fraction and combustion efficiency was proposed to understand the mixing and oxidization experiences of the fuel mixture.
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