In this paper, a numerical simulation is established to model the filling process of atomized natural gas drag reduction agent (DRA) at the pipeline inlet section. The computations are on the basis of the Euler-Lagran...
In this paper, a numerical simulation is established to model the filling process of atomized natural gas drag reduction agent (DRA) at the pipeline inlet section. The computations are on the basis of the Euler-Lagrange method with the standard k-ε turbulence model. The effects of atomizing parameters on the droplets Sauter Mean Diameter (SMD) and the adsorption performance on the wall of pipe are investigated using the validated model. The results show that nozzle diameter and nozzle angle have little effect on the SMD of DRA droplets, whereas the size of the droplets SMD reduces with the increase of atomizing pressure, and the influence of atomizing flow rate is just the opposite.
The influences of the preset angle on the dynamic responses of the typical airfoil section with cubic nonlinear stiffness were investigated under consideration of the aerodynamic flutter onset due to certain angle of ...
The influences of the preset angle on the dynamic responses of the typical airfoil section with cubic nonlinear stiffness were investigated under consideration of the aerodynamic flutter onset due to certain angle of attack. The typical airfoil model with cubic nonlinear stiffness is developed to analyze the plunging and the pitching motions for the airfoil section. Based on the Grossman’s quasi steady aerodynamic model, the aerodynamic lift and the moment can be obtained and then the equation of motion for the airfoil section is derived by applying the Lagrange theorem. The effects of the preset angle and the oncoming flow speed on the nonlinear dynamics are analyzed by means of the bifurcation diagram, the frequency-amplitude diagram, the time history, etc. Simulation results show that the preset angle influences the intensity of the vibration, moderate or severe, stable or unstable, even under certain circumstance, the jump and chaos phenomenon occur; and the oncoming flow speed affects the distribution of the vibration energy for the plunging and the pitching motions. The unstable stall region for the responding parameters should be avoided to keep the airfoil safe in engineering practice. Some qualitative and quantitative rules are obtained for the airfoil design and the flutter suppression.
Li-rich layered oxides (LLOs) are considered as the promising cathode materials for next-generation high energy density lithium-ion batteries (LIBs). However, severe voltage fade and capacity decay hinder their commer...
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The world's marine litter consists mainly of plastic, and 99% of it does not float on the surface of the sea but on the seabed. The plastic carbon footprint necessarily includes the extraction or manufacture of ra...
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The world's marine litter consists mainly of plastic, and 99% of it does not float on the surface of the sea but on the seabed. The plastic carbon footprint necessarily includes the extraction or manufacture of raw materials, the conversion process, the distribution of products, the consumption of specific types of products and the disposal of the final product, as all these stages release carbon into the atmosphere. This work, inspired by marine microplastics and investigates how plastic waste is degraded and transformed in high-pressure, low-temperature seawater, this paper investigates the corrosion of polyethylene terephthalate (PET) and polypropylene (PP) plastics in seawater at high-pressure, using artificial seawater temperatures to simulate ocean temperatures of approximately 4 °C and time settings of 1 day–7 days. The results show that increasing the time enhances the degradation of the plastics and that changing the pressure has little effect on the degradation effect. Understanding its degradation in seawater can help us to better treat plastic waste and thus reduce the carbon footprint of the disposal process.
Topological physics has broadened its scope from the study of topological insulating phases to include nodal phases containing band structure singularities. The geometry of the corresponding quantum states is describe...
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The ongoing work investigates the features of Joule heating and convective condition over a magnetohydrodynamic stagnation point flow of (Formula presented.) nanofluid moving across a curved surface. Moreover, mass su...
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The pressure vessel has used a newly designed water seal structure, and the sealed water is from condensation at low hydrogen concentration. To get the condensation capacity of the water seal branch tube under the pre...
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The pressure vessel has used a newly designed water seal structure, and the sealed water is from condensation at low hydrogen concentration. To get the condensation capacity of the water seal branch tube under the pressure vessel normal operation, the experimental loop named WASETEL was constructed, which is aimed at studying the heat transfer during the process of air-steam mixture condensation inside the inclined branch tube at the condition of low air mass fraction. The inner tube is diameter 0.134 m with length 0.68 m which is connected with diameter 1.4 m, high 2.5 m pressure vessel. A canon camera was set to record the images and videos of the condensate height through glass tube in communicating vessel liquidometer. The experiment was conducted under the pressure ranged from 0.2 to 0.6 MPa, air mass concentration ranged from 0.49 to 6.42% and wall subcooling ranged from 11 to 40 K. The test showed HTC (heat transfer coefficient) would sharply deteriorate with the small air fraction, compared with pure steam condensation, about 0.49% mass fraction of the air will reduce heat transfer coefficient by 70–80%. When air concentration is relatively small, those widely used relations can not predict the condensation well, therefore, a new heat transfer empirical correlation with air mass fraction, pressure and subcooling is proposed, covered all the experimental data within the error band ±13%.
Organic Rankine cycle (ORC) which recovers waste heat in the temperature range of 80°C-140°C was investigated. Exergy efficiencies of various components and ORC system were paid great attention. The working ...
Organic Rankine cycle (ORC) which recovers waste heat in the temperature range of 80°C-140°C was investigated. Exergy efficiencies of various components and ORC system were paid great attention. The working fluids of R245fa and R600a are used. It is found that, for saturated ORCs, the expander inlet temperature has the optimum value, so the system exergy efficiency is maximum. With the increase of heat source temperature, the optimal inlet temperature of the expander is also increased. And also for saturated ORCs, the exergy efficiencies of evaporator and expander are highest efficiency, when evaporator exergy efficiency is increased with increase of heat source temperatures, the expander exergy efficiency is unchanged. The condenser decreased exergy efficiencies by increasing the heat source temperatures.
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