The steady-state incompressible laminar flow in a semi-infinite circular pipe with uniform injection or suction through the porous wall has been investigated. The present analysis simulates also the flow field produced by the burning of inner surface of cyindrical grain in a solid rocket motor. A similar solution of fully non-linear form of the Navier-Stokes equation is calculated numerically. The properties of flow such as velocity components are obtained as functions of injection parameter R=aV/ν. The region near the closed end has been analyzed numerically by means of the finite difference method, and the results is used to inspect the similar solution. It is found that the flow is not similar near the closed end, and that the effect of viscosity of solid end has been confined to the narrow region of x/a<2.
The oscillation of a two-dimensional sail (flexible membrane) in a uniform flow is investigated by applying the method similar to the usual flutter theory. Two cases are considered: The first one is that the slack of the membrane is constant during oscillation, whereas the second is the case in which the membrane is pulled by the weight hung at the trailing edge. The latter somewhat simulates the constant tension condition. Eigenvalue equations including the surface tension, the mass of the membrane and the frequency of oscillation are solved numerically, and the stability characteristics of the sail are discussed. Several modes of periodic oscillation are obtained. Monotonically increasing modes are also obtained when the surface tension is less than a certain critical value.
In this paper we deal with two design methods of adaptive flight control system with stochastic disturbances. The first method ensures to make the expected output error zero asymptotically and the other is based upon the minimum variance control. Both methods are designed via polynomial algebraic method which is a good tool to construct the control system easily. These methods are applied to the flight control system of a small-size high-performance aircraft and numerical simulations under the stochastic environment can be shown to justify the proposed shemes.
Equations for evaluating the performances of a failure detection system, whose task is to detect changes of some parameters in an object system, are derived as functions of the design parameters in the detection system and a design method of the detection system based on the equations is proposed. This detection system consists of the Kalman filters and the Modified Sequential Probability Ratio Test. The usefulness of this design method is examined by means of numerical simulations for the parameter changes in a second order system and for the failure in an aircraft stability augumentation system.
An exact expansion series of the integral function occurring in the lifting surface theory is presented. The series is applicable to nonplanar wings treated in the Laplace domain with the nondimensional Laplace variable p as well as the reduced frequency k which corresponds to the imaginary axis of the p-plane.