DC discharge phenomena in artificial air for an undersea habitat

Abstract

The electrical discharge characteristics of mixtures of helium and oxygen having a constant oxygen partial pressure were investigated to evaluate the safety of electric systems used in an undersea habitat. A comparison is made with the discharge characteristics of air. The spark breakdown voltage of the mixtures of helium and oxygen is at least 1.3 times higher than that of dry air throughout the pressure range studied (from 0.4 to 4.91 MPa). The minimum corona onset voltage was lower at pressures up to about 1.3 MPa than that of dry air. It was confirmed that at pressure higher than 1.3 MPa, it is possible to use even the usual electrical equipment in the mixture of helium and oxygen prevalent in an undersea habitat. It is noted that the spark breakdown voltage for the mixture of helium and oxygen has a plateau in the pressure range from 0.8 to 2 MPa.