As the lighter-than-air (LTA) flight vehicle, the stratospheric airship is a desirable platform to provide communication and surveillance services. During the ascent from sea-level to the mission altitude, the volume of the lifting gas may change significantly, which will result in the change of the center-of-buoyancy (CB). A general calculation method is developed to specify CB for the stratospheric airship with a double-ellipsoid hull and an arbitrary number of the gas cells. The cross-section-integral (CSI) method is used as a basic calculation scenario to specify CB. Considering the complexity in determining the boundary between the helium and air in the gas cell, a searching algorithm is put forward and the specification of CB can be conducted by the iterative calculation. As an important application, the stable condition of the pitch angle is analyzed when the change of CB is involved. Under different initial configurations, the stable pitch angle of the stratospheric airship during the ascent is specified and compared, which shows the advantages of the multi-gas-cell configuration. The results of this paper may provide an important reference for the engineering application of the stratospheric airship.

平流层飞艇作为一种比空气轻（LTA）的飞行器，是提供通信和监视服务的理想平台。在从海平面上升到任务高度的过程中，提升气体的量可能会发生显着变化，这将导致浮力中心（CB）发生变化。开发了一种通用计算方法来指定平流层飞艇的CB，该飞艇具有双椭圆形船体和任意数量的气室。截面积分（CSI）方法用作指定CB的基本计算方案。考虑到确定气室中氦气与空气边界的复杂性，提出了一种搜索算法，可以通过迭代计算来确定CB。作为重要的应用 当涉及到CB的变化时，分析了俯仰角的稳定状态。在不同的初始配置下，指定并比较了上升期间平流层飞艇的稳定俯仰角，这表明了多气室配置的优势。本文的结果可为平流层飞艇的工程应用提供重要参考。