Analysis of Residual Ion Dump (RID) of Diagnostic Neutral Beam (DNB) injector for ITER

Residual Ion Dump (RID) of the 100 kV negative hydrogen ion source based Diagnostic Neutral Beam (DNB) injector, utilizes electrostatic fields for the ion beam deflection. There are four channels formed by five panels of length 1000mm. Each panel consists of 10 actively cooled elements called Tube Elements (TEs) made up of CuCrZr alloy. All TEs are of 1.5 m length with cross-section of 20 mm × 100 mm with a central bore of 16 mm provided for the coolant passage. Water with an inlet temperature of 55 C is used as coolant. Total flow rate and inlet pressure provided for RID are 5 kg/s and 2 MPa respectively. RID is designed for two types of cycles viz; 8.6× 10
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pulse trains of 3s ON/20s OFF and 1.29×10
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modulations of 100ms ON/100ms OFF.