Features of the motion of gel particles in a three-phase bubble column with non-foaming and foaming gas–liquid systems,determined by using experiments of radioactive particle tracking(RPT),have been compared.The trac...Features of the motion of gel particles in a three-phase bubble column with non-foaming and foaming gas–liquid systems,determined by using experiments of radioactive particle tracking(RPT),have been compared.The tracer used is a gel particle which resembles typical immobilized biocatalyst.The tracer trajectory is analyzed to extract relevant information for design purposes.The solid velocity field,turbulence parameters,dispersion coefficients,mixing times and flow transitions are determined and compared.The presence of foam significantly affects many quantified parameters,especially within the heterogeneous flow regime.The hydrodynamic stresses are reduced in the presence of foam,especially close to the disengagement.The dispersion coefficients also decrease,and the solid mixing time is only slightly affected by the presence of foam.Gas holdup,inferred both from RPT experiments and from gamma ray scanning,is higher for foaming systems and leads to a shift in the transition gas velocity towards higher values.展开更多
A tilt sensor based on an intermodal photonic crystal fiber （PCF） interferometer is demonstrated. The sensor consists of a tubular filled with NaC1 aqueous solutions and an intermodal PCF interferometer, which is fo...A tilt sensor based on an intermodal photonic crystal fiber （PCF） interferometer is demonstrated. The sensor consists of a tubular filled with NaC1 aqueous solutions and an intermodal PCF interferometer, which is formed by using a short PCF with two single-mode fibers （SMFs） spliced at both ends, and the air-holes in the splice regions are fully collapsed. The intermodal PCF interferometer is fixed in a rigid glass tubular with a slant orientation, and a half of the PCF is immersed in the NaC1 aqueous solutions, while the other half is exposed in air. When tilting the tubular, the length of the PCF immersed changes so that the transmission spectrum moves. Therefore, by monitoring the wavelength shift, the tilt angle can be achieved. In the experiment, a 0.8-cm-length intermodal PCF interferometer was adopted. The sensitivity of the proposed sensor was obtained from - 1.5461 nm/° to -30.1244 nm/° when measuring from -35.1 ° to 37.05°.展开更多
基金Supported by the FONCyT(PICT2014-0704)CONICET(PIP1122015-0100902CO)Universidad de Buenos Aires(UBACyT 20020130100544BA)
文摘Features of the motion of gel particles in a three-phase bubble column with non-foaming and foaming gas–liquid systems,determined by using experiments of radioactive particle tracking(RPT),have been compared.The tracer used is a gel particle which resembles typical immobilized biocatalyst.The tracer trajectory is analyzed to extract relevant information for design purposes.The solid velocity field,turbulence parameters,dispersion coefficients,mixing times and flow transitions are determined and compared.The presence of foam significantly affects many quantified parameters,especially within the heterogeneous flow regime.The hydrodynamic stresses are reduced in the presence of foam,especially close to the disengagement.The dispersion coefficients also decrease,and the solid mixing time is only slightly affected by the presence of foam.Gas holdup,inferred both from RPT experiments and from gamma ray scanning,is higher for foaming systems and leads to a shift in the transition gas velocity towards higher values.
基金This work was supported by the National Natural Science Foundation of China under Grant No. 61108058, the National Basic Research Program of China （973 Program） under Grant No. 2010CB327804, the Zhejing Province Intemational Science and Technoloty Cooperation Special Programme under Grant No. 2013C24018, the National Key Technology R＆D Program 2011BAF06B02 and the Science and Technology Commission of Shanghai Municipality of China under Grant No. 10595812300. Open Access This article is distributed under the terms of the Creative Commons Attribution License which permits any use, distribution, medium, provided the original credited. and reproduction in any author（s） and source are
文摘A tilt sensor based on an intermodal photonic crystal fiber （PCF） interferometer is demonstrated. The sensor consists of a tubular filled with NaC1 aqueous solutions and an intermodal PCF interferometer, which is formed by using a short PCF with two single-mode fibers （SMFs） spliced at both ends, and the air-holes in the splice regions are fully collapsed. The intermodal PCF interferometer is fixed in a rigid glass tubular with a slant orientation, and a half of the PCF is immersed in the NaC1 aqueous solutions, while the other half is exposed in air. When tilting the tubular, the length of the PCF immersed changes so that the transmission spectrum moves. Therefore, by monitoring the wavelength shift, the tilt angle can be achieved. In the experiment, a 0.8-cm-length intermodal PCF interferometer was adopted. The sensitivity of the proposed sensor was obtained from - 1.5461 nm/° to -30.1244 nm/° when measuring from -35.1 ° to 37.05°.
