For problems of numerical lifting surfaces, comparisons among various approximate methods do not always yield satisfactory knowledge. This paper presents a means which determines accuracy of any approximate method without comparison. Moreover it enables us (1) to achieve optimum ratio NS/NC automatically and (2) to do just necessary calculation for obtaining any prescribed accuracy. This is a sort of "steepest descent method." Computations are proceeded in direction of -grad |grad CL| in NS vs. NC diagrams. An appropriate convergence theory is adopted. Although the method is applied here mainly to Vortex Lattice Method (VLM) for steady wings, it is a universal one which may be applicable to any efficient unsteady VLMs or mode methods.
As a continuation of the first report published in this Journal (Vol. 31, No. 348, 1983), several numerical examples are worked out to illustrate practical computation procedures evolved from our fundamental moment equations. In Sec. 2, the calculation performed previously with the aid of the Φ-function is re-examined by means of the piecewise polynomials and partition method (abbreviated as the P.P. method) in order to verify the accuracy of the latter. In Secs. 3 and 4, the P.P. method is applied to the examples of the inverse problems taken up by BRILEY (1971) and CARTER (1975), and is found to yield satisfactory results. Finally in Sec. 5, a two-dimensional channel flow is calculated by direct integration through the Φ-function.
In recent years, most of high performance aircrafts have been designing by the Active Control Technology (ACT) in order to realize the CAS, RSS, MLC, DFC, FMC and so on. This paper deals with the problem of constucting the two advanced flight control systems such as DFC and vertical CAS. Decoupling control theory, model matching theory and model following servo controller approaches applied in order to solve these problems. First, by using the decoupling theory, flight control laws have been determined for the six open loop CCV modes. Next, the C model following flight control systems which design the vertical CAS are constructed both by using the model matching theory and the model following servo controller scheme. Simulation studies for designing the advanced flight controller of supersonic aircraft are presented in order to demonstrate the effectiveness of the proposed approaches.
In designing a flight control system of the aircraft where only the input and the output can be measured, it is desirable to use adaptive control synthesis approaches. However, most of those approaches can not apply to the plant with the limitation of input amplitude, because those studies are usually done without any lim- itation of input amplitude. In this paper, we deal with the problem of constructing an adaptive flight control system for the aircraft with the angle limitation of control surface. First, by introducing the dispersion flter, two adaptive control schemes for a single-input single-output time-invariant discreate system with the limitation of input amplitude are proposed. Next, these schemes are applied to solve the problem of constructing an adaptive flight control system for both a supersonic aircraft and a VTOL aircraft. Simulation studies which construct an adaptive flight control system of these aircrafts are presented to show the effectiveness and the features of the proposed schemes.
From the point of view to design a practical shock-in-rotor type rotor, the quasi-axisymmetric flow in the subsonic region is considered in the case having the uniform flow with no swirl components at the inlet of rotor blades. The flow in the supersonic region is assurned to be parallel to the axis and satisfy radial equilibrium before the normal shock. The turning angle from the inlet to the normal shock is given. In this report the flow calculation is carried out by giving two conditions (1) angular spacing and (2) angular momentum in the eubsonic region and is applicable to the example with known shapes of both inner and outer casings. The results show the possibilities to design a blade passage for practical use.