The characteristics of heat transfer and flow resistance of highly efficient water cooler which is composed of spirally fluted tubes and rod-baffles have close relation with its structure parameters.Experimental study on the influence of the flute depth of spirally fluted tube on heat transfer and flow resistance performance of the water cooler for turbo-generator stator was carried out.It was shown from the results that: the effect of shell side flow velocity on heat transfer coefficient was greater than that of tube side flow velocity

which meant that heat resistance on shell side was greater than that on the tube side.Hence

more attention should be paid to enhancement of heat transfer on the shell side in order to improve heat transfer performance of water cooler.Within the range of Reynolds number in this experiment

the flute depth of spirally fluted tube had a great effect on heat transfer coefficient of water cooler.A deeper flute led to higher heat transfer performance at the cost of increased flow resistance.At last

based on the experimental results

the correlations of heat transfer and flow resistance for water coolers with different structures were obtained.