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一、引言 当我们对于三轴机械陀螺机载火控系统中的计算陀螺进行必不可少的系统稳定性分析的时候,首先必须求算陀螺阻尼辞的阻尼系数C和弹簧刚度K。然而,在求算这两个重要参数的过程中,我们却遇到了两个困难: 1、阻尼器的阻尼是这样产生的:当因连于陀螺外框架上的阻尼器壳体与惯性块之间发生相对运动的时候,充满阻尼器内腔的粘性液体（甲基硅油）内部将产生粘滞摩擦剪切应力（简称内摩擦力）。由于迎面压力差引起的阻尼力固迎面面积甚小可以忽略,所以上述内摩擦就是所讨论的阻尼器的阻尼力。这种阻尼力对于惯性块的转轴必然形成一个阻尼力矩: M_d=-Cω （1）式中:M_d——阻尼力矩（克力·厘米） C——阻尼器的阻尼系数（克力·厘米·秒/弧度） ω——惯性块相对于转轴的旋转角速度（弧度/秒） 由于惯性块与壳体之间的侧向间隙和端面间隙均很小,所以两处均存在阻尼。对于侧面阻尼的阻尼系数,可以从一般教科书中查到其计算公式,但是对于端面阻尼的阻尼系数,则无现成的计算公式可供查用。 2、由于陀螺阻尼器的弹簧颇象一个缺少一点的问号,形状比较特殊,求其弹簧刚度也查找不到现成的计算公式。 为了解决这两个困难,本文试图根据流体动力学和材料力学的基本原理,推导阻?
I. INTRODUCTION When we carry out the necessary system stability analysis of the gyroscope in the three-axis gyroscope airborne fire control system, we must first calculate the damping coefficient C and the spring stiffness K of the gyroscope damping parameter. However, we encountered two difficulties in calculating these two important parameters: 1, the damping of the damper is such that as a result of damping of the damper housing and the inertial mass Viscous frictional shearing stress (referred to as internal friction) occurs internally in the viscous liquid (methyl silicone oil) filled in the damper lumen during relative motion. The internal friction is the damping force of the damper in question as the damping force due to the difference in frontal pressure is small and insignificantly negligible. This damping force inevitably creates a damping torque for the shaft of the inertial mass: M_d = - Cω (1) where: M_d - damping torque (Cg.cm) C - damping coefficient of the damper Sec / radians) ω - angular velocity of the inertial mass relative to the axis of rotation (radians per second) Because of the small lateral and end clearances between the inertia mass and the housing, damping is present at both locations. For the damping coefficient of side damping, its calculation formula can be found in general textbooks, but there is no formula for calculating the damping coefficient of end damping. 2, due to the spring top of the gyro damper rather like a lack of a question mark, the shape is rather special, find its spring stiffness can not find ready-made formula. In order to solve these two difficulties, this paper attempts to derive resistance according to the basic principles of fluid dynamics and material mechanics.