The experimental investigation on flow drag of the air or high temperture gas flows passing through the tube with inner fans.The range of air temperature is from 287 2K to 259 1K and that of the gas tempreature is from 347 3K to 499 7K.The velocity of the flow varies from 7 3 to 41 7m/s.A correlative equation between Renolds number and drage coefficient is formulated

based on all test data.The results calculated with the correlative equation are in good agreement with the data of tests.