•Fatigue life of damaged landing gear component was numerically predicted.•Topological optimization of landing gear component was carried out.•Numerical simulation of AM process of optimized ...component was conducted.•The effect of interlayer (dwell) time on the residual stresses was analyzed.•Numerical evaluation of the potential position of the crack initiation was carried out.
The torque link is part of the nose landing gear of aircraft. It prevents the piston from turning inside the cylinder of the shock absorber, enabling its up and down motion during the landing and take-off. As such, its structural integrity and life are crucial for aircraft safe operation, but because of complex geometry and variable loading conditions, its fatigue life estimation represents a real challenge. In this paper, fatigue lives of two different designs of the torque links of the light aircraft are evaluated by a numerical approach based on the improved FEM. Firstly, the fatigue life of the damaged torque link was assessed for actual load conditions. Then, improved torque links, obtained through topological optimization, were analyzed and their fatigue life was calculated. Finally, the numerical simulations of the additive manufacturing (AM) process of optimized torque links were carried out, and the fatigue life of these torque links, including residual stresses from AM, were estimated too. The obtained numbers of cycles in all cases were compared and discussed for all torque links cases. This is an advanced approach to fatigue life assessment of optimized printed 3D parts based on numerical simulations of both crack growth and AM process.
The Parton Branching (PB) method describes the evolution of transverse momentum dependent (TMD) parton distributions, covering all kinematic regions from small to large transverse momenta
k
T
. The ...small
k
T
-region is very sensitive both to the contribution of the intrinsic motion of partons (intrinsic
k
T
) and to the resummation of soft gluons taken into account by the PB TMD evolution equations. We study the role of soft-gluon emissions in TMD as well as integrated parton distributions. We perform a detailed investigation of the PB TMD methodology at next-to-leading order (NLO) in Drell–Yan (DY) production for low transverse momenta. We present the extraction of the nonperturbative “intrinsic-
k
T
” distribution from recent measurements of DY transverse momentum distributions at the LHC across a wide range in DY masses, including a detailed treatment of statistical, correlated and uncorrelated uncertainties. We comment on the (in)dependence of intrinsic transverse momentum on DY mass and center-of-mass energy, and on the comparison with other approaches.
Abstract The Parton Branching (PB) method describes the evolution of transverse momentum dependent (TMD) parton distributions, covering all kinematic regions from small to large transverse momenta ...$$k_{\textrm{T}}$$ k T . The small $$k_{\textrm{T}}$$ k T -region is very sensitive both to the contribution of the intrinsic motion of partons (intrinsic $$k_{\textrm{T}}$$ k T ) and to the resummation of soft gluons taken into account by the PB TMD evolution equations. We study the role of soft-gluon emissions in TMD as well as integrated parton distributions. We perform a detailed investigation of the PB TMD methodology at next-to-leading order (NLO) in Drell–Yan (DY) production for low transverse momenta. We present the extraction of the nonperturbative “intrinsic- $$k_{\textrm{T}}$$ k T ” distribution from recent measurements of DY transverse momentum distributions at the LHC across a wide range in DY masses, including a detailed treatment of statistical, correlated and uncorrelated uncertainties. We comment on the (in)dependence of intrinsic transverse momentum on DY mass and center-of-mass energy, and on the comparison with other approaches.
Application of direct radiation pattern estimation in finite difference time domain (FDTD) simulation environment as an alternative to cumbersome near-to-far field transformation is considered. With ...the proposed improvement, direct estimation of the radiation pattern from the field strength samples in FDTD method becomes significantly less sensitive to the antenna geometry and thus more applicable to practically relevant cases. The main idea is to use field samples taken at two different radii to account for antenna geometry. The samples are taken at radii that are as close as possible to the antenna but still not too close to spoil the correctness of the results. The introduced improvement, combined with multigrid simulation domain and higher order accuracy FDTD formulations, reduces the necessary size of the computational domain, which directly leads to reduced memory consumption and a smaller error due to numerical dispersion.
The radiation pattern within high energy quark- and gluon-initiated jets (jet substructure) is used extensively as a precision probe of the strong force as well as an environment for optimizing event ...generators with numerous applications in high energy particle and nuclear physics. Looking at electron-proton collisions is of particular interest as many of the complications present at hadron colliders are absent. A detailed study of modern jet substructure observables, jet angularities, in electron-proton collisions is presented using data recorded using the H1 detector at HERA. The measurement is unbinned and multi-dimensional, using machine learning to correct for detector effects. All of the available reconstructed object information of the respective jets is interpreted by a graph neural network, achieving superior precision on a selected set of jet angularities. Training these networks was enabled by the use of a large number of GPUs in the Perlmutter supercomputer at Berkeley Lab. The particle jets are reconstructed in the laboratory frame, using the kT jet clustering algorithm. Results are reported at high transverse momentum transfer Q2>150GeV2, and inelasticity 0.2<y<0.7. The analysis is also performed in sub-regions of Q2, thus probing scale dependencies of the substructure variables. The data are compared with a variety of predictions and point towards possible improvements of such models.
Fast simulation of showers in calorimeters is very important for particle physics analysis since shower simulation typically takes significant amount of the simulation time. At the same time, a ...simulation must reproduce experimental data in the best possible way. In this paper, a fast simulation of showers in two calorimeters of the H1 experiment is presented. High speed and good quality of shower simulation is achieved by using a shower library technique in which the detector response is simulated using a collection of stored showers for different particle types and topologies. The library is created using the GEANT programme. The fast simulation based on shower library is compared to the data collected by the H1 experiment.
A method for the fast simulation of particle showers in the H1 lead/scintillating-fiber calorimeter is presented. It is based on a shower library technique in which the detector response is simulated ...using a collection of stored showers for different particle types and topologies. The library is created using the GEANT programme. The fast simulation is compared to the data collected by the H1 experiment.
Here, we present a method of respiratory volumes monitoring using a single fibergrating sensor of bending. Measurements are conducted using simple monochromatic interrogation scheme that relies on a ...photodiode measurement of the power transmitted through a long period grating (LPG) sensor at fixed wavelength. Good sensor accuracy in measurements of tidal and minute respiratory volumes for different types of breathing is achieved.
The newly synthesized biphenyldicarboxylic acid Schiff base and its complexes with Cu(II) were synthesized, and their spectroscopic and structural analysis was performed. The reaction of the ligand ...and copper(II) acetate in different solvents resulted in the formation of two solvatomorphic complexes, one with MeOH, and the other with DMF molecules, in the crystal lattice. The differences in the results of the thermal analysis could be explained by the different polarities of the solvents present. SC-XRD analysis revealed that the ligand is coordinated as a dianion, in a pentadentate manner, through two phenoxide oxygen atoms, two azomethine nitrogen atoms, and with the oxygen atom of one carboxylate functioning as a bridge that connects the monomeric units. The coordination polyhedron was described with several parameters obtained from different methods of calculation. The presence of different solvents in the crystal structure results in differences in the H-bond networks, and an overall different crystal packing of the structural units in the obtained complexes.
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