Proper orthogonal decomposition, dynamic mode decomposition, wavelet and cross wavelet analysis of a sloshing flow

Pagliaroli, Tiziano; Gambioli, Francesco; Saltari, Francesco; Cooper, Jonathan E.

doi:10.1016/j.jfluidstructs.2022.103603

Cited by 20 publications

(8 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Theoretical aspects of wavelet analysis are presented by [13] where also cross-wavelet analysis is introduced. The cross-wavelet analysis are deeply used in turbulent flows [14,15] and in other fields like geophysical data series [16]. Briefly describing, wavelet analysis is a tool to investigate both time and frequency information in time series trough the wavelet transform.…”

Section: Methodsmentioning

confidence: 99%

Cross-Wavelet Analysis on Radiation Emitted by the plume of a small-size Solid Rocket Motor

Martellini,

Troiani,

Pagliaroli

2023

J. Phys.: Conf. Ser.

View full text Add to dashboard Cite

This work follow a previous activity that developed a non-intrusive measurements technique for particles velocity ejected from a solid rocket motor based on wavelet analysis. The aim was to detect the particles passage and calculate the axial velocity through an auto-conditioned cross-correlation algorithm. In this study, a wavelet based processing techniques are applied and an innovative methodology based on the cross-wavelet analysis is presented. The objective is to detect the impulsive events associated to the particles crossing the field of view of the acquisition system. Starting from two synthetic signals characterized by a Gaussian peak, each one located at a different time instants, cross-wavelet analysis identify an increase of energy for all the correlation time producing a structure in the time scale comparable to the delay between the peaks. On the experimental database a continuous wavelet transform and a local intermittency measurement are performed to localize high energy events with randomic occurrence in the time series that are associated to the passage of allumina particles. Cross-wavelet analysis present several correlation structures localized in time between the events highlighted by the LIM maps. Results are very promising and could be a very interesting bases for deeper analysis based on wavelet, LIM and cross-wavelet.

show abstract

Section: Methodsmentioning

confidence: 99%

Cross-Wavelet Analysis on Radiation Emitted by the plume of a small-size Solid Rocket Motor

Martellini,

Troiani,

Pagliaroli

2023

J. Phys.: Conf. Ser.

View full text Add to dashboard Cite

show abstract

“…The global coherence coefficient is a statistical tool that can measure the correlation between two time series, with the added benefit of being able to measure on multiple scales. This is an effective way for analyzing data patterns and periodicities without being affected by time [40,42].…”

Section: Global Coherencementioning

confidence: 99%

The Effects of Climate Variation and Anthropogenic Activity on Karst Spring Discharge Based on the Wavelet Coherence Analysis and the Multivariate Statistical

2023

View full text Add to dashboard Cite

This study focused on the impact of anthropogenic activity on magnitude, frequency, and minima of spring discharge. Niangziguan Springs (NS), China, was selected as an example, as its discharge is decreasing due to the combined effects of climate variation and human activity. For exploring the impact of human activity on the spring discharge from climate change, the spring discharges from 1959 to 2015 were divided into two periods: pre-development period (i.e., 1959–1980) and post-development period (i.e., 1981–2015). A polynomial regression model of the spring discharge was developed for the pre-development period. We deduced the model in the post-development period, compared the results with the observed spring discharge, and concluded that the climate variation and human activity caused 6.93% and 32.38% spring discharge decline, respectively. The relationships of spring discharge with Indian Summer Monsoon (ISM), East Asian Summer Monsoon (EASM), E1 Niño Southern Oscillation (ENSO), and Pacific Decadal Oscillation (PDO) were analyzed by wavelet analysis during the two periods. The results illustrated that the monsoons (i.e., ISM and EASM) were dominated by climate factors that affect the NS discharge versus climate teleconnections (i.e., ENSO and PDO). According to different time scales, human activities have had an impact on the periodicity of NS discharge, which altered the periodicities of the spring discharge at inter-annual time scales, but the periodicities at intra-annual and annual time scales have remained the same between the two periods. Under the effects of human activity, the local parameter of non-stationary general extreme value (NSGEV) distribution varied with time. The predicted spring discharge minimum value is supposed to be 4.53 m3/s with a 95% confidential interval with an upper boundary of 6.06 m3/s and a lower boundary of 2.80 m3/s in 2020. The results of this study would benefit the management of spring discharge and water resources.

show abstract

“…This investigation successfully demonstrated the presence of additional damping induced by sloshing (see Refs. [19][20][21]). Following this result, Single-Degree-Of-Freedom (SDOF) experiments were developed as part of the SLOWD project to isolate the vertical component of tank motion in order to the study the dissipative behavior of sloshing.…”

Section: Introductionmentioning

confidence: 99%

Sloshing reduced-order model trained with Smoothed Particle Hydrodynamics simulations

Martinez-Carrascal,

Pizzoli,

Saltari

et al. 2023

Nonlinear Dyn

Self Cite

View full text Add to dashboard Cite

The main goal of this paper is to provide a Reduced Order Model (ROM) able to predict the liquid induced dissipation of the violent and vertical sloshing problem for a wide range of liquid viscosities, surface tensions and tank filling levels. For that purpose, the Delta Smoothed Particle Hydrodynamics (δ-SPH) formulation is used to build a database of simulation cases where the physical parameters of the liquid are varied. For each simulation case, a bouncing ball-based equivalent mechanical model is identified to emulate sloshing dynamics. Then, an interpolating hypersurface-based ROM is defined to establish a mapping between the considered physical parameters of the liquid and the identified ball models. The resulting hypersurface effectively estimates the bouncing ball design parameters while considering various types of liquids, producing results consistent with SPH test simulations. Additionally, it is observed that the estimated bouncing ball model not only matches the liquid induced dissipation but also follows the liquid center of mass and presents the same sloshing force and phase-shift trends when varying the tank filling level. These findings provide compelling evidence that the identified ROM is a practical tool for accurately predicting critical aspects of the vertical sloshing problem while requiring minimal computational resources.

show abstract

Proper orthogonal decomposition, dynamic mode decomposition, wavelet and cross wavelet analysis of a sloshing flow

Cited by 20 publications

References 38 publications

Cross-Wavelet Analysis on Radiation Emitted by the plume of a small-size Solid Rocket Motor

Cross-Wavelet Analysis on Radiation Emitted by the plume of a small-size Solid Rocket Motor

The Effects of Climate Variation and Anthropogenic Activity on Karst Spring Discharge Based on the Wavelet Coherence Analysis and the Multivariate Statistical

Sloshing reduced-order model trained with Smoothed Particle Hydrodynamics simulations

Contact Info

Product

Resources

About