At Study or the Dynamic Response or Arcs: Time Constants Low-Current Arcs Under Small Air Flow

Mayr-type arc models, which are useful for relating factors determining circuit breaker interrupting limits, may represent arcs cooled by gas blast as well as by thermal conduction. Preliminary studies with air velocities below 100 feet per second show marked effects of nozzle flow on the model parameters. Arc time constants may be reduced an order of magnitude by such a flow and depend on pressure or velocity gradients as well as fluid velocities.