Wei L.,The 718th Research Institute of CSIC |
Huang Y.,Nanjing University of Technology
Wuji Cailiao Xuebao/Journal of Inorganic Materials | Year: 2015
Porous ceramic membranes on macroporous metal support without any intermediate layer were prepared by a solid-state particle sintering assisted with carbon. Nano-scale TiO2 particle and macroporous stainless-steel tube were employed as membrane material and support, respectively. For surface coating, polyvinyl alcohol (PVA) was used as adhesive agent, and dip-coating procedure was performed. Effect of different sintering atmosphere (i.e., nitrogen and air) during the preparation of porous ceramic membrane was investigated. For characterization, scanning electron microscopy, X-ray diffraction, thermogravimetry and porometry analyses were conducted, respectively. It was found that serious peeling of the ceramic membrane was occurred when the coated sample was heat-treated in air, but an integrated membrane was achieved when the sintering atmosphere was replaced with nitrogen. Owing to the existence of carbon generated by the carbonization of PVA in nitrogen at high temperature, the mixed structure of TiO2 and carbon can help to weaken the membrane sintering stress which is caused by poor quality of the support surface and by mismatch of the thermal-expansion-coefficients of ceramic and metal. After the sintering of TiO2 particle, the generated carbon can be removed by heat-treatment in air, resulting in a porous TiO2/stainless-steel membrane. The membrane thickness and mean pore size are 10 μm and 0.21μm, respectively, and the corresponding nitrogen flux is 1.72 m3/(m2·h·kPa) at room temperature. ©, 2015, Science Press. All right reserved.
Cao W.,Harbin Institute of Technology |
Fu Y.-J.,The 718th Research Institute of CSIC |
Wang C.,Harbin Institute of Technology |
Wei Y.-J.,Harbin Institute of Technology
Tuijin Jishu/Journal of Propulsion Technology | Year: 2012
To predict the off-design performance of bubbly water ramjet, the mathematical models were constructed under some assumptions. The thrust and propulsion efficiency were obtained by numerical simulation. The influences of gas mass flow rate, ship velocity and ambient pressure on the performance were emphatically investigated for a comprehensive understanding of bubbly water ramjet. Results indicate that the thrust increases with increasing gas mass flow rate, but the efficiency decreases. When the ship velocity is higher than the design value, the thrust is higher. However, the maximum efficiency is obtained at the design ship velocity. With increasing ambient pressure, both the thrust and propulsion efficiency decrease. By means of regulating the gas mass flow rate with feedback, it can drive the ramjet output the thrust close to the drag of the vehicle, and then the uniform navigation is achieved at arbitrary velocity in the range of the work speed.
Fu Y.-J.,The 718th Research Institute of CSIC
Tuijin Jishu/Journal of Propulsion Technology | Year: 2013
To predict the off-design performance of mist jet engine, the mathematical models were constructed under some assumptions. The thrust and propulsion efficiency were obtained by numerical simulation. The effects of ship velocity and ambient pressure on the performance were emphatically investigated for a comprehensive understanding of mist jet engine. When the ship velocity is higher than the design value, the gas mass flow rate must be increased. In this condition, the engine works with higher efficiency and less thrust. With increasing ambient pressure, less gas needs to be injected, but the thrust and propulsion efficiency of the engine decrease. By means of regulating the gas mass flow rate and initial pressure with feedback, it can drive the engine output the thrust close to the drag of the vehicle with varied velocity.
Zhang L.,The 718th Research Institute of CSIC |
Dong Y.,The 718th Research Institute of CSIC
Huaxue Fanying Gongcheng Yu Gongyi/Chemical Reaction Engineering and Technology | Year: 2013
The CO2 absorption in different alkanolamine solutions in a high gravity rotating bed packed with metal form has been studied. The experimental results indicate that different alkanolamine solution has different efficiency on CO2 absorption, with monoethanolamine solution the highest. The mass transfer can be enhanced with the increase of bed rotating speed and alkanolamine concentration. Volumetric mass transfer coefficient KGa tends to increase with increasing liquid flow, but the growth rate gradually decreases. The KGa first increases and then decreases with the absorption temperature.
Cai X.-B.,The 718th Research Institute of CSIC |
Liu D.-Y.,The 718th Research Institute of CSIC
Hedianzixue Yu Tance Jishu/Nuclear Electronics and Detection Technology | Year: 2010
Measurement uncertainty of gamma-ray detectors for gamma spectrum logging were evaluated, and established a mathematical model to identify the elements constitute about the measurement uncertainty, resolution was 8.958%, the relative combined standard uncertainty was 1.065%, k =1. According to evaluation result, detector would be normally made use of gamma spectrum logging tool.