The expansion of a two-dimensional flow due to the resistance of a wire gauze was studied analytically by applying revised Taylor's method in which the resistance of a gauze was replaced by the momentum change of flow from sources distributed on the plane of the gauze. Measurements were also made on the expansion of flow in a two-dimensional smoke wind-tunnel, and a good agreement between the calculated and measured profiles of flow was found. Additionally, flow observation and velocity-distribution measurement were carried out for a model diffuser designed by the analytical method.
Results of an extensive experimental program on the stability of thin cylindrical shells with cut-out under axial compression are presented and discussed. The experimental data indicate that the buckling coefficient varies with effective length-radius and radius-thickness ratio. Some other reports have been showed the buckling coefficient between R/t and L/R relations. However, there is no indicating the above synthetic investigation which introduced the effect of cutout in a shell. To determine the buckling coefficient with a circular hole, there empirical equation studied in here using the method of averages and least squares. In addition, the critical buckling load of thin cylindrical shell with multiple circular holes also reported.
A simple relation is derived concerning to LITVC (Liquid Injection Thrust Vector Control) characteristics based on a model taken into consideration of the momentum exchange between the injectant and the main nozzle flow. In this model, it is assumed that the injectant forms an equivalent slender body being swept away by main nozzle flow after injection and the side force is generated with the disturbed wall pressur around the equivalent slender body. General conclusions from numerical calculations using the slender body theory for typical bodies of revolution are effectively used to derive a simple relation. This relation expressing the dependency of Isps (specific impulse of secondary injection) on the injectant flow rate and the chamber pressure has been examined by correlating experimental values obtained in the series of experiments conducted by the Institute of Space and Aeronautical Science of University of Tokyo.
A lifting surface theory is presented for the arbitrary blade motion in incompressible flow. The theory accounts for the effects of the unsteady aerodynamics fairly exactly and is shown to simulates the blade bending-torsion flutter boundary satisfactorily which the usual quasisteady theory has hitherto failed to predict. The theory is also shown to give the results which agree well with those of other references when applied to two dimensional wing and three dimensional rectangular wings.
By the well-known method of superposition, the velocity distributions of large numbers of airfoils are calculated from those of a limited number of mean lines and thickness forms in engineering accuracy. However, the analytical base of this method is not yet provided, and it is studied here. It is presented that the method is generally verified by the first approximation of Moriya's theory, which has been accepted as reliable since 1937. However, the correction factor is required for the a'bove method in the leading edge domain, and at there, the velocity due to the mean line is reduced all the more, when the thicker thickness form in formed around it.
A unique device, named "dihedral effect adjusting fin" is introduced in the development of Mitsubishi twin-turboprop business plane, MU-2G. This device, a fin attached to the wing tip tank, causes a modification of interference effect of wing tip tank with the main wing, and facilitates the adjustment with assurance of dihedral effect of an airplane with wing tip tank. In this note, the idea of dihedral effect adjusting fin and its application to the development of MU-2G plane are reviewed.
The inclination and yaw characteristics on the recovery ratio of a temperature probe at high subsonic speeds were investigated experimentally and the following results were obtained. (1) The recovery ratio may be taken constant within yaw angles of |θ|≤20°. (2) The recovery ratio may be taken constant with inclination angles at the low Mach number, but it is influenced by inclination angles at the high Mach number. (3) In the case of a small inclination angle (|α|≤15°), the flow properties normal to the probe axis can be calculated with a reasonable accuracy by using the recovery ratio of zero inclination angle.