Selective protection using direct current (DC) circuit breakers is a promising solution for DC fault isolation. In contrast, higher fault currents and fault energies make DC fault interruption a critical issue in DC distribution systems. A fault isolation strategy is proposed to achieve fast dissipation of circuit breaker energy using gallium-indium-tin (GIT) liquid metal alloy for energy dissipation. The liquid metal alloy cavity structure and energy dissipation working principle are analyzed. A magnetohydrodynamic energy dissipation simulation model in a liquid metal arc is created. The effect of short-circuit current on the pressure distribution of a liquid metal arc is analyzed. An experimental platform consisting of LC oscillating circuits with modifiable short-circuit currents is constructed to mimic the oscillations of a liquid metal arc. An investigation is conducted into the impact of arc initiation and igniting techniques on energy absorption in liquid metal arcs. The findings theoretically validate a unique liquid metal energy consumption model for DC circuit breakers.