CAD-DIRECTED INSPECTION PLANNING FOR FREEFORM SURFACE USING CONTACT PROBES

A methodology for CAD-directed measurement of freeform surface using a coordinate measuring machine equipped with a touch-trigger probe is presented, mainly including adaptive sampling of measurement points and registration of freeform surface. The proposed sampling method follows four steps： Freeform surface is fitted by bi-cubic B-spline; Curvedness measure of the surface is computed; Given a number of sampling points, an iterative algorithm is constructed for selecting a set of measurement points by employing the curvedness information; The measurement points is regularized for tradeoff between maximizing the measurement accuracy and minimizing the sampling time and cost. The aforesaid algorithm is demonstrated in term of a marine propeller blade. An offset surface registration method is presented to improve alignment accuracy of freeform objects, and Monte Carlo simulation is conducted to verify the effectiveness of the method.

Experimental study of single-translated fieldreversed configuration in KMAX

For collisional merging fleld-reversed conflgurations(FRCs),it is desired to have both FRCs tuned to be approximately the same,as well as to optimize each FRC to have high temperature and high translation speed so as to retain most of the equilibrium flux after traveling a distance to the middle plane for merging.The present study reports the experimental study of a single-translated FRC in the KMAX-FRC device with various diagnostics,including a triple probe,a bolometer,several magnetic probe arrays,and a novel 2 D internal magnetic probe array.According to the measurements conducted in the present study,a maximum toroidal magnetic fleld equal to~1/3 of the external magnetic fleld inside the FRC separatrix radius is observed,and the typical parameters of a single-translated FRC near the device’s mid-plane are ne~(2–4)×10^(19)m^(-3),T_(e)~8e V,T_(i)~5 e V,r_(s)~0.2 m,l_(s)~0.6 m andφ_(()p(RR))~0.2 m Wb.The 2 D magnetic topology measurement revealed,for the flrst time,the time evolution of the overall internal magnetic flelds of a single-translated FRC,and an optimized operation regime is given in the paper.

Design and performance of Hall probe measurement system in CSNS

Background The construction of China Spallation Neutron Source(CSNS)was started in 2011 and will be completed in 2018.The phase I CSNS facility consists of an 80MeV HLinac,a 1.6GeV Proton Rapid Cycling Synchrotron(RCS),two beam transport lines and a target station.Magnets in the RCS and transport lines should be measured before being installed in the tunnel.Method In this paper,a new hall probe measurement system is described.The design and performance of the hall probe measurement system is presented.Conclusions The measurement results meet the design requirements.Some key issues were solved in the process.

COORDINATE MEASURING MACHINE PROBING ACCESSIBILITY

The accessibility of coordinate measuring machines (CMMs) in dimensional inspection is studied. The problem of computing the global accessibility cone is solved using a method of angle representation. Otherwise, the length and volume of probe are considered sufficiently so that all the feasible probe orientations could be determined for the inspection of a workpiece when a touch trigger probe is used and the shortcoming of abstracting a probe as an infinite half line could be overcome completely. In the end, an example is given to explain the method.

Liquid Metal Heat Transfer in an Inclined Tube Affected by a Longitudinal Magnetic Field

This paper presents results of hydrodynamic and heat transfer investigations in liquid metal flow affected by a longitudinal magnetic field in an inclined tube with respect to tokamak cooling problem.Experimental study has been conducted for the tube with slope 1\5 to the horizon which corresponds to the conditions oflTER project in case the LM flow faced longitudinal MF.The results obtained in the regimes without the MF,may be interesting for the design of nuclear reactors cooled by LM and metallurgical processes.

Fluidization of particles in SCW fluidized bed:Voidage distribution of emulsion phase

Supercritical water(SCW)fluidized bed reactors convert biomass to fuels without pollutants emission.In this work,experimental studies were carried out to investigate voidage distribution in an SCW fu-idized bed by capacitance probes.Quartz sands with different particle sizes were fluidized by SCW under system pressure of 20-27 MPa and temperature of 410-570℃.The effect of operation conditions on voidage distributions of the emulsion phase(e.g.averaged voidage and probability density)is discussed.A predicting correlation between voidage and superficial velocity in emulsion phase is proposed.The relative error of the correlation is within+25%.These research results provide useful guidance for the optimization of supercritical water gasification technology.