In practical engineering,only pressure sensors are allowed to install to detect leakage in most of oil transportation pipelines,while flowmeters are only installed at the toll ports.For incompressible fluid,the leakag...In practical engineering,only pressure sensors are allowed to install to detect leakage in most of oil transportation pipelines,while flowmeters are only installed at the toll ports.For incompressible fluid,the leakage rate and amount cannot be accurately calculated through critical pressure conditions.In this paper,a micro-element body of the pipeline was intercepted for calculation.The relationship between radial displacement and pressure of pipe wall was studied based on the stress-strain equation.Then,the strain response of pipeline volume with pipeline pressure was obtained.The change in volume expansion of pipeline was used to characterize leakage of incompressible fluid.Finally,the calculation model of leakage amount of incompressible fluid was obtained.To verify the above theory,the pipeline expansion model under pressure was established by COMSOL software for simulation.Both simulation results and deduction equations show that the volumetric change has a quadratic parabolic relationship with the change of pipeline pressure.However,the relationship between them can be approximately linear when the pressure change is not too large.In addition,the leakage of incompressible fluid under the pressure of 0 MPa-0.8 MPa was obtained by experiments.The experimental results verify the linear relationship between leakage of incompressible fluid and the change of pipeline pressure.The theoretical and experimental results provide a basis for the calculation of leakage of incompressible fluid in the pipeline.展开更多
To improve the integration of Fano devices,we design a T-shaped waveguide coupling micro-ring resonator(MRR)structure to achieve a single cavity with Fano resonance in the whole spectral bands.The mathematical relatio...To improve the integration of Fano devices,we design a T-shaped waveguide coupling micro-ring resonator(MRR)structure to achieve a single cavity with Fano resonance in the whole spectral bands.The mathematical relationship between the phase factor,the coupling coefficient of the bus waveguide,and the Fano resonance slope extinction ratio(ER)is established.The electron beam exposure process is used to obtain a device with an insertion loss of~3 dB.The maximum ER of the Fano lineshape exceeds 15 dB,and the slope ratio(SR)is 251.3 dB/nm.This design improves the compactness of the Fano resonant device.展开更多
文摘In practical engineering,only pressure sensors are allowed to install to detect leakage in most of oil transportation pipelines,while flowmeters are only installed at the toll ports.For incompressible fluid,the leakage rate and amount cannot be accurately calculated through critical pressure conditions.In this paper,a micro-element body of the pipeline was intercepted for calculation.The relationship between radial displacement and pressure of pipe wall was studied based on the stress-strain equation.Then,the strain response of pipeline volume with pipeline pressure was obtained.The change in volume expansion of pipeline was used to characterize leakage of incompressible fluid.Finally,the calculation model of leakage amount of incompressible fluid was obtained.To verify the above theory,the pipeline expansion model under pressure was established by COMSOL software for simulation.Both simulation results and deduction equations show that the volumetric change has a quadratic parabolic relationship with the change of pipeline pressure.However,the relationship between them can be approximately linear when the pressure change is not too large.In addition,the leakage of incompressible fluid under the pressure of 0 MPa-0.8 MPa was obtained by experiments.The experimental results verify the linear relationship between leakage of incompressible fluid and the change of pipeline pressure.The theoretical and experimental results provide a basis for the calculation of leakage of incompressible fluid in the pipeline.
基金supported by the State Grid Zhejiang Electric Power Corporation Information Telecommunication Branch(No.B311XT21004G)the 111 Project of China(No.D17021)+1 种基金the National Natural Science Foundation of China(No.61903042)the Beijing Natural Science Foundation(No.4214081)。
文摘To improve the integration of Fano devices,we design a T-shaped waveguide coupling micro-ring resonator(MRR)structure to achieve a single cavity with Fano resonance in the whole spectral bands.The mathematical relationship between the phase factor,the coupling coefficient of the bus waveguide,and the Fano resonance slope extinction ratio(ER)is established.The electron beam exposure process is used to obtain a device with an insertion loss of~3 dB.The maximum ER of the Fano lineshape exceeds 15 dB,and the slope ratio(SR)is 251.3 dB/nm.This design improves the compactness of the Fano resonant device.
