Electrostatic fluid injection system

A fluid injection system comprising:

• a mixing chamber (280) locatable in an exhaust gas conduit upstream of a selective catalytic reduction device (SCR) (295), the chamber providing a flow path for exhaust gas and a space for receiving an injected fluid;
• an injector having a plurality of bundled capillary tubes (202) each having an inlet (204) and an outlet (206) wherein the inlet is configured to receive a fluid for injection into the chamber, the injector being mounted on the chamber with the tube outlets in fluid communication with the space in the chamber;
• a base plate (248) disposed in the chamber spaced from and aligned with the bundled capillary tubes;
• a voltage supply (240) connected to the tubes and to the base plate (248) wherein the voltage supply provides a charge to the tubes and to the base plate to create an electric field to the fluid in the tubes;
• and
• a valve (230) disposed on a wall of the chamber for at least one of priming and purging of the tubes.