An apparatus, system, and method are disclosed for intermittently delivering fluid. An injector intermittently delivers a first quantity of fluid over a first time interval. In one embodiment, the injector is passively cooled. In a certain embodiment, the injector delivers the first quantity of fluid responsive to a fluid flow measurement of a flow meter. An orifice diverts the first quantity of fluid from a primary fluid supply system over a second time interval without decreasing the supply of fluid to a primary load within a flow rate range while the fluid pressure remains within a pressure range. An accumulator accumulates at the least the first quantity of fluid as a fluid charge with positive energy.