Solenoid

About: Solenoid is a research topic. Over the lifetime, 19278 publications have been published within this topic receiving 114721 citations.

Computational and experimental investigation on solenoid valve dynamics

Abstract: A generally applicable, synthetic simulation model and computational tool has been elaborated for dynamic simulation of solenoid valves (SV) applied as control elements in fast-response pneumatic fluid power systems. The SV of case study has been modeled as a system consisting of coupled magnetodynamic and mechanical subsystems. At the present state of investigation, fluid dynamic effects are not considered in the model. The appropriateness of the model has been verified by experimental data. The simulation model resolves the valve body motion and the solenoid current at a high accuracy. It has been pointed out in the concerted numerical and experimental studies that the valve body performs repetitive flexible collision (bouncing) at its opened end-position. Such initial vibrating motion of valve body may affect favorably the SV fluid transmission characteristics, transferring momentum to the fluid in the orifice cross-section. The investigation reveals that the valve body penetrates to the flexible contact surface at its opened end-position. This results in an actual valve body displacement 50 percent higher than the geometrical displacement (determined from the SV geometry with neglect of penetration). Such modified displacement may result in flow transmission characteristics differing significantly from the SV design condition (considering the geometry with no deformation). The SV flow transmission characteristics will be studied in a SV model supplemented with fluid mechanical submodels.

High source potential upstream of a current-free electric double layer

Abstract: Large plasma potentials (up to ∼80V) are measured upstream of a current-free electric double layer generated in a helicon rf argon discharge for a constant rf power of 250 W (at 13.56 MHz) and for low operating pressures (<2mTorr) using an electrostatic ion energy analyzer. The energy of the Ar+ ion beam formed by acceleration through the potential drop of the double layer is found to be strongly correlated with the large source potentials: both the source potential and the beam energy increase with decreasing pressure. The creation of the double layer depends on the magnetic field generated by the solenoid near the closed end (glass plate) of the helicon source.

The KATRIN superconducting magnets: Overview and first performance results

Abstract: The KATRIN experiment aims for the determination of the effective electron anti-neutrino mass from the tritium beta-decay with an unprecedented sub-eV sensitivity. The strong magnetic fields, designed for up to 6 T, adiabatically guide β-electrons from the source to the detector within a magnetic flux of 191 Tcm2. A chain of ten single solenoid magnets and two larger superconducting magnet systems have been designed, constructed, and installed in the 70-m-long KATRIN beam line. The beam diameter for the magnetic flux varies from 0.064 m to 9 m, depending on the magnetic flux density along the beam line. Two transport and tritium pumping sections are assembled with chicane beam tubes to avoid direct "line-of-sight" molecular beaming effect of gaseous tritium molecules into the next beam sections. The sophisticated beam alignment has been successfully cross-checked by electron sources. In addition, magnet safety systems were developed to protect the complex magnet systems against coil quenches or other system failures. The main functionality of the magnet safety systems has been successfully tested with the two large magnet systems. The complete chain of the magnets was operated for several weeks at 70% of the design fields for the first test measurements with radioactive krypton gas. The stability of the magnetic fields of the source magnets has been shown to be better than 0.01% per month at 70% of the design fields. This paper gives an overview of the KATRIN superconducting magnets and reports on the first performance results of the magnets.

Shut-off means for air-actuated planter

Abstract: A shut-off means for an air-actuated planter is disclosed, which includes a butterfly valve located within the air manifold of the planter unit, which is connected to a rotational means further connected to a solenoid. A power source is connected to the solenoid which, with the activation of a switch, causes current to flow to the solenoid, rotating the rotational means, and causing the butterfly valve to move within the air manifold. In this manner, air within the air manifold may be blocked at any point where the air valve is located, shutting off the air source to one or more planter units.