Browse Prior Art Database

Magnetohydrodynamic Velocity Modulation of a Jet

IP.com Disclosure Number: IPCOM000077714D
Original Publication Date: 1972-Sep-01
Included in the Prior Art Database: 2005-Feb-25
Document File: 2 page(s) / 35K

Publishing Venue

IBM

Related People

Toupin, RA: AUTHOR [+2]

Abstract

In the technology of fluid jets in general and in particular as applied to ink-jet printing technology, it is desired that a fluid jet, for example of ink, emerging from a nozzle be broken into a series of regularly spaced droplets at some point removed from the nozzle. When such a fluid jet emerges from a nozzle its subsequent motion is unstable and the jet breaks up into the droplets. These droplets will form at some distance from the nozzle and at some particular time from the time the jet left the nozzle. In general, these times and distances are irregular. However, it is proposed that the mean velocity of the emerging jet be modulated at an appropriate frequency which enhances an unstable mode of the free jet, by which means the distance and time can be made uniform for the droplet formation.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 52% of the total text.

Page 1 of 2

Magnetohydrodynamic Velocity Modulation of a Jet

In the technology of fluid jets in general and in particular as applied to ink-jet printing technology, it is desired that a fluid jet, for example of ink, emerging from a nozzle be broken into a series of regularly spaced droplets at some point removed from the nozzle. When such a fluid jet emerges from a nozzle its subsequent motion is unstable and the jet breaks up into the droplets. These droplets will form at some distance from the nozzle and at some particular time from the time the jet left the nozzle. In general, these times and distances are irregular. However, it is proposed that the mean velocity of the emerging jet be modulated at an appropriate frequency which enhances an unstable mode of the free jet, by which means the distance and time can be made uniform for the droplet formation.

As opposed to the existing devices for synchronizing droplet formation, the nozzles shown in the figures can be fixed and rigid and need not vibrate or undergo any motion at the frequency of desired droplet formation. This may be achieved by passing the current through the streaming fluid in the nozzle in a direction normal to the axis of flow, and by simultaneously subjecting the stream to an impressed magnetic field with a component normal to both the axis of flow and the current, thus creating a force which acts directly upon the moving stream of fluid. If either the current or the magnetic field is made periodic in time and the other constant, then the force will be periodic in time and have a component along the axial direction of the fluid. T...