A piston-cylinder apparatus was established to measure the solubility and diffusivity of air in dimethyl silicone oils and in hydraulic oils based on the PVT state equation of air and the solution of unsteady one-dime...A piston-cylinder apparatus was established to measure the solubility and diffusivity of air in dimethyl silicone oils and in hydraulic oils based on the PVT state equation of air and the solution of unsteady one-dimensional diffusion equation.The measured diffusivity-temperature relation can be well fitted by the Arrhenius equation for engineering applications.The correlation between the solute diffusivity D and solvent viscosity μ is examined.In terms of Eyring＇s activation theory,the activation in the air-silicone-oil diffusion process is quite different from that in the momentum transport of the silicone oil：the activation entropy of the former is positive while that of latter is negative.However,the activation enthalpies of the two processes are in the same order of magnitude,which leads to the observation that Dμ/T is roughly constant.展开更多
The mass transfer model describing the separation of essential oils from plant materials has been proposed and the mass transfer coefficient has been obtained by fitting the present model to the experimental data for ...The mass transfer model describing the separation of essential oils from plant materials has been proposed and the mass transfer coefficient has been obtained by fitting the present model to the experimental data for three kinds of plant materials. The validity of the model has been verified. To im' prove the vapor-solid contact, a mechanical agitator has been installed in the steam distillator. The effect of agitating rate on mass transfer coefficient has also been examined.展开更多
Based on the energy equation of gas-liquid flow in pipeline,the explicit temperature drop formula for gas-liquid steady state calculation was derived.This formula took into consideration the Joule-Thomson effect,impac...Based on the energy equation of gas-liquid flow in pipeline,the explicit temperature drop formula for gas-liquid steady state calculation was derived.This formula took into consideration the Joule-Thomson effect,impact of terrain undulation and heat transfer with the surroundings along the line.Elimination of temperature iteration loop and integration of the explicit temperature equation,instead of enthalpy energy equation,into the conjugated hydraulic and thermal computation have been found to improve the efficiency of algorithm.Then,the inner wall temperature of gas-liquid flow was calculated by using explicit temperature equation and inner wall convective heat transfer coefficient of mixed flow which can be obtained by liquid convective heat transfer coefficient and gas convective heat transfer coefficient on the basis of liquid holdup.The temperature results of gas-liquid flow and inner wall in the case example presented both agree well with those in professional multiphase computational software OLGA.展开更多
The effects of three factors on combustion performance of petroleum coke, Herin Coal and Shenmu Coal have been studied, including the ratio of primary air, excess air factor, and the swirling intensity of outer second...The effects of three factors on combustion performance of petroleum coke, Herin Coal and Shenmu Coal have been studied, including the ratio of primary air, excess air factor, and the swirling intensity of outer secondary air. The experiments were carried out on a one-dimensional furnace with dual channel swirling burner, in which temperature of center furnace, emission of air pollutants, and burn-out rate of fuel were measured. The results provide the optimal ratio of primary air, excess air factor and swirling intensity of outer secondary air for the fuels. The combustion performance of petroleum coke B is much better than petroleum coke A, but worse than Hejin coal and Shenmu coal. In addition, the burn-out rate of petroleum coke depends much more on the temperature in terminal stage of combustion than in the early stage of combustion.展开更多
基金Supported by the National Natural Science Foundation of China （50675202）
文摘A piston-cylinder apparatus was established to measure the solubility and diffusivity of air in dimethyl silicone oils and in hydraulic oils based on the PVT state equation of air and the solution of unsteady one-dimensional diffusion equation.The measured diffusivity-temperature relation can be well fitted by the Arrhenius equation for engineering applications.The correlation between the solute diffusivity D and solvent viscosity μ is examined.In terms of Eyring＇s activation theory,the activation in the air-silicone-oil diffusion process is quite different from that in the momentum transport of the silicone oil：the activation entropy of the former is positive while that of latter is negative.However,the activation enthalpies of the two processes are in the same order of magnitude,which leads to the observation that Dμ/T is roughly constant.
文摘The mass transfer model describing the separation of essential oils from plant materials has been proposed and the mass transfer coefficient has been obtained by fitting the present model to the experimental data for three kinds of plant materials. The validity of the model has been verified. To im' prove the vapor-solid contact, a mechanical agitator has been installed in the steam distillator. The effect of agitating rate on mass transfer coefficient has also been examined.
基金Project(2011ZX05000-026-004) supported by the National Science & Technology Specific Program of ChinaProject(2010D-5006-0604) supported by the China National Petroleum Corporation (CNPC) Innovation FoundationProject(51004167) supported by the National Natural Science Foundation of China
文摘Based on the energy equation of gas-liquid flow in pipeline,the explicit temperature drop formula for gas-liquid steady state calculation was derived.This formula took into consideration the Joule-Thomson effect,impact of terrain undulation and heat transfer with the surroundings along the line.Elimination of temperature iteration loop and integration of the explicit temperature equation,instead of enthalpy energy equation,into the conjugated hydraulic and thermal computation have been found to improve the efficiency of algorithm.Then,the inner wall temperature of gas-liquid flow was calculated by using explicit temperature equation and inner wall convective heat transfer coefficient of mixed flow which can be obtained by liquid convective heat transfer coefficient and gas convective heat transfer coefficient on the basis of liquid holdup.The temperature results of gas-liquid flow and inner wall in the case example presented both agree well with those in professional multiphase computational software OLGA.
基金Acknowledgments This work is supported by Natural Science Foundation of China （NO. 51076127） and the Clean Combustion ＆ Gas-solid Two-Phase Flow group in Xi＇an Jiaotong University.
文摘The effects of three factors on combustion performance of petroleum coke, Herin Coal and Shenmu Coal have been studied, including the ratio of primary air, excess air factor, and the swirling intensity of outer secondary air. The experiments were carried out on a one-dimensional furnace with dual channel swirling burner, in which temperature of center furnace, emission of air pollutants, and burn-out rate of fuel were measured. The results provide the optimal ratio of primary air, excess air factor and swirling intensity of outer secondary air for the fuels. The combustion performance of petroleum coke B is much better than petroleum coke A, but worse than Hejin coal and Shenmu coal. In addition, the burn-out rate of petroleum coke depends much more on the temperature in terminal stage of combustion than in the early stage of combustion.
