Overdamped arc discharge data and an AWA model

Experimental data on overdamped arc discharges are compared with a lumped-circuit discharge mode employing the arc welder´s ansatz (AWA). The AWA prescribes that the arc resistance-varies time as R_a(t)=V*/|I(t)|, where V* is a positive constant and I(t) is the discharge current. In the circuit, in addition to the time-dependent arc resistance R_a and a small arc inductance L _a, there are an external time-dependent series resistance R_o, inductance L_o, and source capacitance C, the values of which are given. The AWA theory is compared with an observed arc current pulse I(t) by using these given values and normalizing the theory to one point on the data curve; an adequate fit to the data is obtained. Data for the dynamic arc resistance R_a(t) are also compared with the AWA prescription and with other available theories for R_a, which also use a one-point normalization. The AWA form for R_a compares favorably with the other theories