Sewage water pumps very often are equipped with impellers featuring a small number of blades which therefore provide big cross sections of the flow channel. Single-blade impellers comprise the smallest possible number of blades and are known as non-clogging pumps. But severe disadvantages occur during operation, because the timevariant flow in such pumps results in periodic unsteady flow forces...

Two major branches of engineering mechanics are fluid mechanics and structural mechanics, with many practical problems involving the effect of the first on the second. An example is the design of an aircraft's wings to bend within reasonable limits without breaking under the action of lift forces exerted by the air flowing over them; another is the maintenance of the structural integrity of a d...

A finite element solution based on equevalent elements is proposed for the static and dynamic analysis of tallhigh tensioned cable antennas. To reduce high number of degrees of freedom in space frame body of a structure, a simple equivalent beam element is defined for each simulative substructure. This numerical procedure is applicable to analyze complex three dimensional assemblies of substruc...

Concussions occur as a result of forces directed to the head or neck, or from impulsive forces transmitted from the body to the head. They result in the rapid onset and spontaneous recovery of short-lived impairment of neurologic function. Concussions represent a functional, rather than structural, disturbance, and do not result in abnormalities on standard structural imaging. This article disc...

In coupled simulation of uid-structure phenomena the important unknowns for structural design are the interface forces caused by the dynamic uid pressure acting on the structure. By means of variationally consistent post-processing we may compute interaction forces that obey the principle of virtual work. Error estimates of the recovered quantities may be provided by solving a related (dual) ad...

Agribusiness industries are facing numerous challenges and opportunities resulting from various fundamental forces. An understanding of the forces that are shaping and shifting the competitive landscape is useful to not only understand the strategic positioning decisions of the firms in these industries, but also the dramatic structural changes that are occurring in the food production, process...

A time domain approach is used in this paper to identify unknown dynamic forces applied on two dimensional frames using the measured dynamic structural responses for a sub-structure in the two dimensional frame. In this paper a sub-structure finite element model with short length of measurement from only three or four accelerometers is required, and an iterative least-square algorithm is used t...

In this paper, we consider the autonomous dynamical system linear or linearized with 2 degrees of freedom. In the system of equations of 4th degree, the structure generalized forces appear: K(q) the conservative forces, N(q) the non-conservative forces, D(q̇) the dissipative forces, G(q̇) the gyroscopically forces. In the linear system, these forces from the different structural combinations can ...

The nonlinear static procedure (NSP) or pushover analysis in FEMA-273 [FEMA, 1997] has become a standard procedure in current structural engineering practice. Seismic demands are computed by nonlinear static analysis of the structure, which is subjected to monotonically increasing lateral forces with an invariant height-wise distribution until a target displacement is reached. None of the curre...

A time domain approach for predicting the coupled flutter and buffeting response of long span bridges is presented. The frequency dependent unsteady aerodynamic forces are represented by the convolution integrals involving the aerodynamic impulse function and structural motions or wind fluctuations. The aerodynamic impulse functions are derived from experimentally measured flutter derivatives, ...