微型发动机柔性转子的动平衡

On Dynamic Balancing of Flexible Rotor of Chinese Micro-Aeroengine

针对微型发动机转子的结构特点，提出一种在自身壳体和轴承中由空气驱动，只采用一个平衡校正面的柔性转子动平衡方法，使平衡精度大大提高。试车表明发动机整机振动很小，说明平衡方法对提高此类微型发动机动平衡品质十分有效。

In our development of micro-aeroengine, we found that its vibrations were too large and we could not satisfy the requirments for dynamic balancing of international G6. 3 standard.We overcome this difficulty by making use of the recommendations outlined in the international GI standard.We now can ensure that each micro-aeroengine made in a factory and dynamically balanced by us can meet the requirments of G6. 3 standard.The rotor is replaced by a simplified model as shown in Fig. 1 in order to facilitate calculations. We deem that such simplification is allowable because engineering accuracy is still retained. Then well known principles of engineering vibration theory are used to derive eqs. (1) through(3).After rotor is dyflamically balanced by us, we find that residual unbalance is only about 50% of what is allowed by international standard G6. 3. That our dynamic balancing is well done is further confirmed by putting the rotor through long -term test. Fig. 4 shows the typical variation of overload coefficient with speed. It can be seen that overload coefficient in general is only 1￣3g, with a peak value of about 5. 5g, whereas it is customary to allow a maximum of 6￣8g for aeroengine.