AN ELECTRIC ARC ACROSS AN AIR STREAM
Abstract
The paper has three main aims: to describe the important features of the two-dimensional problem of an arc column across a low subsonic air stream; to present a simple model of the arc column which has proved qualitatively useful in the past; and to demonstrate by analysing experimental results that the model is not quantitatively adequate. A principal feature of the problem is that the cross-sectional area of the arc depends on the current passing through the arc, on the velocity of the undisturbed stream and on the ambient pressure and temperature. This feature is incorporated in the simple model, which employs an equivalent arc of circular cross-section carrying the same current and having no convection inside it. The experimental results, inferred from measurements on moving arcs at atmospheric pressure, are analysed in terms of Reynolds number, Nusselt number and drag coefficient. The results for the arc are found to differ greatly from results for solid circular cylinders, even when an allowance is made for loss of energy from the arc by radiation. It is concluded that the equivalent arc, is not a satisfactory model of an arc across an air stream, and possible reasons for this, as well as possible lines of improvement, are given.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1965
- Accession Number
- AD0464544
Entities
People
- E. G. Broadbent
- W. T. Lord
Organizations
- Royal Aircraft Establishment