The mechanical behavior of multi-cracks under compression has become a very important project in the field of fracture mechanics and rock mechanics. In this paper, based on the previous theoretical results of the failure criterion for brittle materials under compression, experiment study is implemented. The specimens are square plates and are made of cement, sand and water, and the cracks are made by using a very thin film (0.1 mm). The relations of material compressive strength versus crack spacing and the lateral confining stress are obtained from experimental results. The experimental results agree well with the failure criterion for brittle materials under compression, which indicates that the criterion is effective and applicable.
] Theoretical calculation formula of punch force during tube extrusion has been proposed by means of slab method. On the basis of theoretical and experimental study, it is found that theoretical results of extrusion force given by the calculating formula approached to that of the experiment, and the relative errors are less than 20％. It is also found that the extrusion force is closely related to deformation temperature, lubricant and the ratio of extrusion. The calculating formula of extrusion force is given by considering the factors which are the conical angle of die, and the friction coefficient between the deformation zone and the extrusion container, and the friction coefficient between the undeformed zone and the mandrel. Key Words: Tube, Extrusion, Force, Physical model
Abstract
This paper presents results from tests completed on a rotor system fitted with pendulum-type torsional vibration absorbers. A review of the associated theoretical background is also given and the experimental and theoretical results are compared and contrasted. An overview of the test apparatus is provided and its unique features are discussed. To the best knowledge of the authors, this is the first time that a systematic study of the dynamic behavior of torsional vibration absorbers has been undertaken in a controlled environment.
The performance of two-dimensional jet-flap cascades is determined experimentally. Stream deflection angles are presented as a function of the ratio of jet to mainstream momentum flux at chord spacing ratios of 0.375 and 0.75. Results obtained with conventional jet-flap airfoils (normal blowing near trailing edge) are in good agreement with published theoretical results. Tangential blowing jet-flap airfoils (tangential blowing over a rounded trailing edge) are shown to approximately double the turning effectiveness of the cascade.
This paper presents an experimental study of turbulent buoyant jets discharged vertically through a single circular submerged pipe into a large body of stagnant nonstratified water of finite depth. The experiments were carried out in laboratory facilities consisting of a closed system capable of maintaining steady-state conditions. The temperature characteristics of a hot rising plume were obtained, for numerous flows, as a function of discharge Froude number and discharge depth. The governing equations to predict jet characteristics are also presented, using an integral approach. A computer was used for reduction of experimental data and the numerical solution to the governing equations. The experimental and theoretical results compared favorably.
This paper presents an analytical and experimental study of a cylindrical rod vibrating in a viscous fluid enclosed by a rigid, concentric cylindrical shell. A closed-form solution for the added mass and damping coefficient is obtained and a series of experiments with cantilevered rods vibrating in various viscous fluids is performed. Experimental data and theoretical results are in good agreement.
Discussion: “An Experimental Study of Compressible Flow Through Convergent-Conical Nozzles, Including a Comparison With Theoretical Results” (Thornock, R. L., and Brown, E. F., 1972, ASME J. Basic Eng., 94, pp. 926–930)