Cable Pulley Test

<div>This report will investigate the interactions regarding a cable pulley system within the nose landing gear. There is the possibility of tension drops occurring within this system. A test was done to determine the tension values within the system, this test was to isolate two possibilities that could</div><div>cause the tension drop. These two possibilities were structural deflection within the nose landing gear or the tension loss occurring within the pulley cluster. With this test it was found that there are in fact tension drops when the pulley cluster was used on a rigid system without the structural deformations of the nose landing gear. There are some discrepancies where a basic cable test was done without the pulley cluster and no tension drop was found. This would lead to an investigation to occur after this test</div><div>to determine why the tension drop happens with the cable and pulley cluster interaction. Some reasons to the tension drop within the pulley cluster would be unwinding of the cable as well as deformation occurring. There is however no definite answer for the tension drop as the observation was difficult within such a confined and small space of the pulley cluster.</div>

Cable Pulley Test

<div>This report will investigate the interactions regarding a cable pulley system within the nose landing gear. There is the possibility of tension drops occurring within this system. A test was done to determine the tension values within the system, this test was to isolate two possibilities that could</div><div>cause the tension drop. These two possibilities were structural deflection within the nose landing gear or the tension loss occurring within the pulley cluster. With this test it was found that there are in fact tension drops when the pulley cluster was used on a rigid system without the structural deformations of the nose landing gear. There are some discrepancies where a basic cable test was done without the pulley cluster and no tension drop was found. This would lead to an investigation to occur after this test</div><div>to determine why the tension drop happens with the cable and pulley cluster interaction. Some reasons to the tension drop within the pulley cluster would be unwinding of the cable as well as deformation occurring. There is however no definite answer for the tension drop as the observation was difficult within such a confined and small space of the pulley cluster.</div>

Revealing the High-Modulus Mechanism of Polyimide Films Prepared with 3,4′-ODA

To prepare PIs (polyimides) with desirable thermal and mechanical properties is highly demanded due to their widespread applications in flexible optoelectronic devices and printed circuit boards. Here, the PI films of BPDA/4,4′-ODA, BPDA/3,4′-ODA, PMDA/4,4′-ODA, PMDA/3,4′-ODA systems were prepared, and it was found that the PIs with 3,4′-ODA always exhibit a high modulus compared with the PIs with 4,4′-ODA. To disclose the mechanism of high-modulus PI films with 3,4′-ODA, amorphous PI models and uniaxial drawing PI models were established and calculated based on MD simulation. The PI structural deformations at different length scales, i.e., molecular chain cluster scale and repeat unit scale, under the same stress were detailed and analyzed, including the variation of chain conformation, bond length, bond angle, internal rotation energy, and torsion angle. The results indicate that PIs with 3,4-ODA have higher internal rotation energy and smaller deformation with the same stress, consistent with the high modulus.

Distributed Fibre Optic Sensing (DFOS) for Deformation Assessment of Composite Collectors and Pipelines

Due to the low costs of distributed optical fibre sensors (DFOS) and the possibility of their direct integration within layered composite members, DFOS technology has considerable potential in structural health monitoring of linear underground infrastructures. Often, it is challenging to truly simulate the actual ground conditions at all construction stages. Thus, reliable measurements are required to adjust the model and verify theoretical calculations. The article presents a new approach to monitor displacements and strains in Glass Fiber Reinforced Polymer (GFRP) collectors and pipelines using DFOS. The research verifies the effectiveness of the proposed monitoring solution for health monitoring of composite pipelines. Optical fibres were installed over the circumference of a composite tubular pipe, both on the internal and external surfaces, while loaded externally. Analysis of strain profiles allowed for calculating the actual displacements (shape) of the pipe within its cross-section plane using the Trapezoidal method. The accuracy of proposed approach was positively verified both with reference spot displacement transducer as well as numerical simulations using finite element method (FEM). DFOS could obtain a comprehensive view of structural deformations, including both strains and displacements under externally applied load. The knowledge gained during research will be ultimately used for renovating existing collectors.

Conceptual Design, and Fluid-Structural Interaction Based Investigations on Highly Maneuverable Unmanned Amphibious Vehicle for Ravage Removal Applications at Various Oceanic Working Environments

Nowadays Unmanned Amphibious Vehicles [UAVs] are employed in many applications such as oceanic research, deep sea exploration, mapping, naval surveillance, and disaster monitoring and fisheries protection. The use of UAVs in military and other applications has steadily increased over the few years. On the other hand, there has been a tremendous increase in ocean exploitation. Though technologies are increasing incrementally, nature is exploited adversely. Advancement in ocean transportation, shipping, sewage wastes filled the ocean with tonnes and tonnes of debris and oil wastes. This ravage fills affect the complete marine ecosystem. This in turn makes the ocean toxic. Advancements have been made in recent years to clean up the oil spills. The noted projects such as Sea bin, super high-tech sponges etc. All these innovations are the static one which cannot move along the waves of the ocean. The static form of these inventions could not be used to clean to the larger extent. Therefore, this study aims to build an UAV which is a movable one, can detect the debris and clean those by incorporating existing cleaning techniques. Since the UAV has to sub merge under the water to some extent, it should be designed in such a way by considering both the hydro-dynamical and hydro structural aspects of it. The unique point in the paper covers the flexible cum efficient design of the UAV. The design of the tropical bird is chosen for the efficient model of the UAV. With the few known parameters of this species, the UAV has been designed to achieve the maximum efficiency. The tropical bird chosen has the higher rate of climb, which is the desired requirement for this study. The propeller is uniquely designed based on aerodynamic cum hydrodynamic data so as to balance both the effects. With the design data estimated using analytical formulae, the UAV has been constructed. Following the design, the complete analyses on aerodynamic, aero-structural, hydrodynamic and hydro structural computations are completed. Finally, the employment techniques such as ravage removal mechanism, integrated rotor for the selected application will be integrated. CATIA and ANSYS Workbench are the major tools involved in these comparative investigations, in which modelling of UAV is computed in CATIA and fluid pressure, structural deformations, stresses on UAV are computed through ANSYS Workbench.

Combining high-speed planar PIV and motion tracking of a flexible cylinder in cross-flow

Most modeling studies investigating the flow dynamics in vegetation canopies are limited to rigid models as proxies for vegetation elements. However, most canopies embody some degree of structural flexibility, resulting in aeroelastic mechanisms coupling the motion of the vegetation with the surrounding flow. Studies addressing flexible canopies typically quantify either the flow or the plant motion independently, thus missing the instantaneous coupling between turbulent stresses and structural deformations. Few experiments have been devoted to measuring both quantities simultaneously. Okamoto and Nezu (2009) utilized a combined PIV-PTV technique to capture both flow and canopy motion. However, only the motion of the stem tips was captured, as opposed to the deformation of the entire stem. Py et al. (2006) employed digital image correlation (DIC) to quantify the motion of crop canopies using in-field images. However, the wind itself was not measured across the domain. The present work presents an experimental technique that can be utilized to study the flow–structure interaction in flexible canopies, and that could be extended to other flexible and/or moving objects. High-speed PIV data of the flow surrounding an idealized canopy element, consisting of a flexible cylinder, together with the corresponding displacement field throughout the cylinder were simultaneously obtained combining fluorescent imaging and refractive index matching (RIM).

Origins and pathways of deeply derived carbon and fluids observed in hot spring waters from non-active volcanic fields, western Kumamoto, Japan

Natural springs containing volcanic and magmatic components occur in association with these activities. However, features of deeply originated fluids and solutes were less documented from fields, where active volcanic and magmatic activities are not distributed. To characterize the presence of deep components and identify their major pathways 28 groundwater samples (~ 1230 m deep) were collected from hot spring sites located at western coast of Kumamoto, southwestern Japan, where the typical subduction related magmatisms are absent. The samples were measured for dissolved ion concentrations and stable isotope ratios (δ2HH2O, δ18OH2O, δ13CDIC and δ34SSO4) that were compared with data of 33 water samples from vicinity surface systems. The groundwaters were classified into three types based on major hydrochemistry: high Cl− fluid, low concentration fluid, and high HCO3− fluid. Our data set suggests that the high Cl− fluid was formed by saline water mixing with aquifer waters of meteoric origin and subsequently evolved by reverse cation exchange. The low concentration fluid is identical to regional aquifer water of meteoric origin that was subjected to cation exchange. The high HCO3− fluid showed the highest HCO3− concentrations (~ 3,888 mg/l) with the highest δ13CDIC (up to − 1.9‰). Based on our carbon mixing model and observed δ2HH2O and δ18OH2O shifts, it is suggested that dissolved carbon of mantle origin and small fraction of fluids generated in deep crust were transported towards surface through structural weakness under open tectonic setting. These deeply derived components were then mixed with waters in the surface systems and diluted. Their impacts on surface hydrological systems were limited in space except few locations, where deeply connected pathways are anticipated along active structural deformations.

An analytical model of static stiffness for linear rolling guideway considering the structural deformations of carriage

To solve the deformations and stiffnesses changes of linear rolling guideway under different loads, and to provide reference for the structural design of the carriage, this paper presents an analytical model of three-degrees-of-freedom static stiffness for linear rolling guideway considering the structural deformations of the carriage. In this study, first, the contact loads and elastic deformations between balls and raceways caused by external loads and preload were obtained by Hertz contact theory. The elastic deformations between balls and raceways were described by the change of the curvature centers of the carriage raceways. Next, according to the constraints and loading conditions of the carriage, the elastic beam theory was introduced, and the structural deformations of the carriage under the contact loads were equivalent to the deformations of two cantilever beams. Then, the external loads and the displacements of the carriage were derived by the static equilibrium conditions of the carriage. At last, the proposed equivalent model of carriage structure deformations was validated by comparing the calculated deformations of the carriage with those from a commercial program under various loading conditions, and the accuracy of the static stiffness model proposed in this paper was further verified by the experimental results in the reference. The results show that the calculated structural deformations of carriage matched the deformations calculated by a commercial program well. Also, with relative errors of 4.4–17.5%, the calculated stiffnesses using the model proposed in this paper more closely matched the measured stiffnesses. Clearly, there is a better match between the calculated results of the proposed model and the measurements than with the conventional rigid model.