Reserve Bank of India Governor Urjit Patel on Thursday faced a noisy black flag demonstration from Congress workers at the NSCBI Airport here.He was on his way back to Mumbai after the apex bank's board meeting here.At least 20 Congress workers surrounded his car shouting "Urjit Patel hai hai" and waved black flags, throwing security personnel into a tizzy.As Patel got out of his car, the demonstrators went near the official and tried to heckle him, blaming the RBI Governor for the "crisis in the country" due to the demonetisation of high value currency notes.The Central Industrial Security Force (CISF) and West Bengal police personnel somehow managed to escort Patel to safety inside the airport.