Project/Area Number 
14550426

Research Category 
GrantinAid for Scientific Research (C)

Allocation Type  Singleyear Grants 
Section  一般 
Research Field 
Measurement engineering

Research Institution  Keio University 
Principal Investigator 
HONDA Satoshi Keio University, Science & Technology, Professor, 理工学部, 教授 (90092329)

Project Period (FY) 
2002 – 2003

Project Status 
Completed (Fiscal Year 2003)

Budget Amount *help 
¥2,900,000 (Direct Cost: ¥2,900,000)
Fiscal Year 2003: ¥1,100,000 (Direct Cost: ¥1,100,000)
Fiscal Year 2002: ¥1,800,000 (Direct Cost: ¥1,800,000)

Keywords  Flow measurement / Tomograph / Inverse problems / Signal processing / Reguralization / Electromagnetic flowmeter / プロセストモグラフィ / プロセス計測 / 逆問題解析 
Research Abstract 
Electromagnetic flowmeters using Faraday's law have been one of the standard meters to measure liquid flowrate in industry. A conventional electromagnetic flowmeter has a uniform magnetic field and point electrodes in a circular pipe. Such a flowmeter has a flow signal which is proportional to the flowrate when the velocity profile in the liquid is axisymmetric. The ideal field which induces the flow signal proportional to the flowrate free from velocity profile does not exist. Conversely, it is possible to evaluate velocity profiles through the proper design of the magnetic field. In previous study 2dimensional tomography system with eight magnetic poles and eight signal pickup electrodes was reported. It was reported that when the flow was conditioned to be fully developed and axially symmetric, the reconstruction of 2dimensional velocity distribution could be achieved from induced signals. In this paper, the author proposes a new design of the 3D field excitation with two sets of eight magnetic poles and of eight signal pickup electrodes. This research aims at the estimation of 3dimensional velocity distribution in the pipe. For numerical simulation the laminar swirling flow was supposed. The axial component is the same as Poiseuille flow. The tangential velocity components represent a swirl. In order to reconstruct the tangential velocity, the constraints of nonslipness at the pipe wall, equation of continuity, and tangential velocity near the wall were effective. A new method for reguralization parameters is proposed. The proposed method applies to Lcurved one. When there are two reguralization parameters, the parameter surface is described in 3D space. The reguralization parameters were determined by the proposed method. It is concluded that the reconstruction of 3D velocity distribution can be achieved from induced signals. Numerical simulation study showed the feasibility of the 3D flow velocity tomography.
