| With the rapid development of modern industries, Energy saving and Security for turbomachine has been paid more and more attention. There are many factors that determine the safety, stability and long term operation, such as vibration beyond standard limit, blades rupture, seal leakage and so on. Seal gas exciting is one of the main reasons for blade rupture and vibration beyond standard limit. Seal failure always induces seal leakage. So, it is much valuable for both theory and application to develop the fault self-recovery regulation methods for seal gas exciting and leakage in turbomachine.A special method to calculate the straight honeycomb seals' dynamic coefficients is presented. The perturbation variables are taken into the governing equations obtained by a single-control-volume model. That forms the zeroth-order and first-order equations. The dynamic coefficients are induced through the expression of the pressure distribution in the end. The calculation is simplified and improved through the introduction of Laplace transform, Taylor expansion and simplification of the first-order equations. It is shown that the calculation results of the dynamic coefficients of honeycomb seal and its experimental data have the same order of magnitude. While the effective damping coefficient which presents the overall influence of the honeycomb seals on the rotor stability is analyzed, its calculation results are quite approximate to its experimental data. It approves the feasibility of this method .And the calculation results can be a quantitative measure for the vibration reduction of the honeycomb seals. Furthermore, the influence of the rigidity and damping variables of the honey seal on rotor stability can also be analyzed, through the calculated dynamic coefficients. It is especially significant for the regulating on the seal gas exciting and the seal leakage.The characteristics of blade's seal gas exciting regulating by honeycomb seal has been investigated to solve the problem of blade fatigue fracture. The blade vibration (amplitude) under different seal clearances has been surveyed while the blade-tip seal adopting smooth seal or honeycomb seal, respectively. The amplitude decreases while the seal clearance increasing, is reduced apparently with honeycomb seal instead of smooth seal. Compared to smooth seal, honeycomb seal leads to the amplitude decrease nearly 25% at the best state for common blades at the measuring point in the experiment. The wake field of blade tip seal has been visualized with smoke wire technique, and the velocity distribution has been drawn. The mechanism of regulating blade-tip seal gas exciting by honeycomb seal has been discussed in this section. The fluid velocity in the cavity can be reduced and energy can be dissipated by adopting honeycomb seals. Accordingly, the gas exciting and the blade vibration can be weakened. In a word, the honeycomb seal is an effective method to regulate seal gas exciting, and fault self-recovery regulation is realized from the generation source of blade vibration.The characteristics of blade's seal gas exciting regulating by the combination of honeycomb seal and shunt injection has been studied experimentally and discussed. Honeycomb seals, as well as smooth seals are tested under the different conditions (different seals' clearances and shrouded blades), with the gas spraying on the blade tip clearance in the reverse direction of the main flow. It indicates in the experiment that shunt injection has the damping effect on blade vibration, and the blade vibration magnitude at the measuring point can be reduced by 17% and 14% at the best state, respectively, under the conditions of smooth seal and honeycomb seal. Nearly 37% of the blade vibration at the measuring point in the experiment can be reduced at the best state by adopting honeycomb seal and shunt injection simultaneously. Consequently, proper honeycomb seal and suitable shunt injection are very useful to regulate seal gas exciting. It is meaningful for avoiding blade rupture, improving the rotor stability and realizing the fault self-recovery.Air pumping is proposed to regulate blade's seal gas exciting. With air pumping in the top seal, more than 10% of the blade vibration at the measuring point in the experiment can be reduced. For unshrouded blade, the vibration reduction of air pumping with positive nozzle angle is better than with negative angle. For shrouded blade, the vibration reduction of air pumping is even better—up to 23% of the initial vibration can be reduced at the measuring point in the experiment. Furthermore, the vibration reduction is better with wider shroud. The characteristics of seal gas exciting regulating by tip air pumping have been systematically studied in this section. The blade vibration is aggravated by the injection flow while the nozzle angle is less than 30°. By contrast, the blade vibration is gradually reduced with the increasing of injection pressure while the angle exceeds 40°, and the best effect can even reach to 81% of the initial vibration at the measuring point in the experiment.The fault self-recovery regulation methods for seal leakage and water erosion in steam turbine have been discussed, and new structures of honeycomb seal suitable for steam turbine have been presented and designed. Water droplets in turbine low pressure cylinder are collected and drained through annular flumes which are designed in the bottom plate of blade-tip honeycomb seal. So the self-recovery for blade fault caused by the water erosion is done. To solve shaft seal leakage, new structures of honeycomb seal, which are the combination of the traditional honeycomb seal and labyrinth seal, are presented and designed. The hidden threats that caused shaft seal leakage are eliminated, so that the shaft seal leakage can be prevented. The new structures of shaft honeycomb seal are suitable for flue gas seal, steam seal and bearing box seal of flue gas turbine as well. The fault self-recovery regulation method for oil seal leakage in large motor has been discussed, and a compound oil seal combined adjustable automatic tracking technology with honeycomb seal has been designed. The main reason for oil leaking into rotor's interior is the negative pressure in rotor's interior caused by fan rotation and seal failure. A structure combined honeycomb seal with the contact seal, while charged with nitrogen between them, is designed to isolate negative pressure. Oil seal leakage is rooted out by pressure equilibrium and honeycomb seal. The wear resistance gets better with longevity through the adjustable automatic tracking seal instead of traditional felt seal. The threats leaded to seal failure are eliminated at the beginning. Moreover, the adjustable automatic tracking seal provides self-repairing in a relatively long time. Applications in industries indicate that oil seal leakage has been solved successfully by the compound oil seal combined adjustable automatic tracking technology with honeycomb seal.
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