EXPERIMENTAL INVESTIGATION ON MASS-HEAT TRANSFER OF SHROUDED ROTOR-STATOR SYSTEM

According to the theory of analogy between heat transfer and mass transfer,the mass transfer technique is applied to a shrouded rotor-stator system for experimental,investigation on its heat transfer.An experimental model is set up:The cooling air is blown axially from the front edge of the stator,and the naphthalene(C₁₀H₈) sublimation technique is employed to obtain both local and average mass-transfer coefficients for the rotor surface coated by naphthalene.The heat transfer characteristics of the shrouded rotor-stator system are investigated using the mass transfer analog technique.The emphasis is put on analyzing the effects of the following parameters on the transfer characteristics:The ratio of axial gaps G_s 、 the ratio of axial clearance G_c 、the rotational Reynolds number Reθ and flow coefficient C_w .Correlations are obtained experimentally,conclusions are drawn for the test conditions as follows:1.The average mass transfer coefficient increases with increase of the flow coefficient C_w and the rotational Reynolds number Reθ ;2.The average mass transfer coefficient decreases with increase of the ratio of axial gap Gs and the ratio of axial clearance G_c ;3.The peak of local mass transfer coefficient radically moves out with reference to impingement point.