Computational Singular Perturbation Method and Tangential Stretching Rate Analysis of Large Scale Simulations of Reactive Flows: Feature Tracking, Time Scale Characterization, and Cause/Effect Identification. Part 2, Analyses of Ignition Systems, Laminar and Turbulent Flames

Valorani, Mauro; Creta, Francesco; Ciottoli, Pietro Paolo; Galassi, Riccardo Malpica; Goussis, Dimitris A.; Najm, Habib N.; Paolucci, Samuel; Im, Hong G.; Tingas, Efstathios-Al.; Manias, Dimitris M.; Parente, Alessandro; Li, Z.; Grenga, Temistocle

doi:10.1007/978-3-030-44718-2_4

Cited by 7 publications

(4 citation statements)

References 64 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…From a dynamics perspective, the quantity that is correlated with the system's ignition delay time, is the system's characteristic timescale [142,156],…”

Section: H 2 O 2 Additionmentioning

confidence: 99%

“…• the amplitude participation index (API), which measures the relative importance of each reaction to each CSP mode's amplitude (f i ) [140][141][142]. For the fast (exhausted) modes where by definition f i ≈ 0 due to the negligible projection of the vector field to the fast directions in the phase space, API identifies the reactions participating the most to the established equilibria [143,144].…”

mentioning

confidence: 99%

See 1 more Smart Citation

The chemical dynamics of hydrogen/hydrogen peroxide blends diluted with steam at compression ignition relevant conditions

Tingas

2021

Fuel

View full text Add to dashboard Cite

“…From a dynamics perspective, the quantity that is correlated with the system's ignition delay time, is the system's characteristic timescale [142,156],…”

Section: H 2 O 2 Additionmentioning

confidence: 99%

mentioning

confidence: 99%

The chemical dynamics of hydrogen/hydrogen peroxide blends diluted with steam at compression ignition relevant conditions

Tingas

2021

Fuel

View full text Add to dashboard Cite

“…The details of the CSP method used herein and its algorithmic tools have been discussed elsewhere (see for instance [83][84][85][86][87]), and only a brief summary is provided here. Consider the system of species and temperature equations in the general form of…”

Section: Computational Singular Perturbation (Csp) and Its Algorithmi...mentioning

confidence: 99%

Asymptotic Analysis of Detonation Development at SI Engine Conditions Using Computational Singular Perturbation

Dimitrova¹,

Sanal²,

Luong³

et al. 2022

Preprint

View full text Add to dashboard Cite

The occurrence and intensity of the detonation phenomenon at spark-ignition (SI) engine conditions is investigated, with the objective to successfully predict super-knock and to elucidate the effect of kinetics and transport at the ignition front. The computational singular perturbation (CSP) framework is employed in order to investigate the chemical and transport mechanisms of deflagration and detonation cases in the context of 2D high-fidelity numerical simulations. The analysis revealed that the detonation development is characterized by: (i) stronger explosive dynamics and (ii) enhanced role of convection. The role of chemistry was also found to be pivotal to the detonation development which explained the stronger explosive character of the system, the latter being an indication of the system's reactivity. The role of convection was found to be enhanced at the edge of the detonating front, thereby suggesting that it is the result and not the cause of the detonation onset. Moreover, the increased contribution of convection was found to be related mainly to heat convection. Remarkably, the detonation front was mainly characterized by dissipative and not explosive dynamics. Finally, diffusion was found to have negligible role to both examined cases.

show abstract

“…In this work, we will identify the SIM of the reduced order model by following the Computational Singular Perturbation (CSP) method [9,10,11], because of our past involvement in research activities connected with this specific methodology [12,13,14]. A review of the theoretical framework of CSP with applications can be found in [15,16].…”

Section: Theorymentioning

confidence: 99%

The spectral characterisation of reduced order models in chemical kinetic systems

Valorani

Galassi

Ciottoli

et al. 2022

Combustion Theory and Modelling

View full text Add to dashboard Cite

The size and complexity of multi scale problems such as those arising in chemical kinetics mechanisms has stimulated the search for methods that reduce the number of species and chemical reactions but retain a desired degree of accuracy. The time scale characterization of the multi scale problem can be carried out on the basis of local information such as the Jacobian matrix of the model problem and its related eigen-system evaluated at one point P of the system trajectory.While the original problem is usually described by ordinary differential equations (ODEs), the reduced order model is described by a reduced number of ODEs and a number of algebraic equations (AEs), that might express one or more physical conservation laws (mass, momentum, energy), or the fact that the long term dynamics evolves within a so-called Slow Invariant Manifold (SIM).To fully exploit the benefits offered by a reduced order model, it is required that the time scale characterization of the n-dimensional reduced order model returns an answer consistent and coherent with the time scale characterization of the N -dimensional original model.This manuscript discusses a procedure for obtaining the time scale characterization of the reduced order model in a manner that is consistent with that of the original problem. While a standard time scale characterization of the (original) N -dimensional original model can be carried out by evaluating the eigen-system of the (N × N ) Jacobian matrix of the vector field that defines the system dynamics, the time scale characterization of the n-dimensional reduced order model (with n < N ) can be carried out by evaluating the eigen-system of a (n × n) constrained Jacobian matrix, JC , of the reduced vector field that accounts for the role of the constraints.

show abstract

Computational Singular Perturbation Method and Tangential Stretching Rate Analysis of Large Scale Simulations of Reactive Flows: Feature Tracking, Time Scale Characterization, and Cause/Effect Identification. Part 2, Analyses of Ignition Systems, Laminar and Turbulent Flames

Cited by 7 publications

References 64 publications

The chemical dynamics of hydrogen/hydrogen peroxide blends diluted with steam at compression ignition relevant conditions

The chemical dynamics of hydrogen/hydrogen peroxide blends diluted with steam at compression ignition relevant conditions

Asymptotic Analysis of Detonation Development at SI Engine Conditions Using Computational Singular Perturbation

The spectral characterisation of reduced order models in chemical kinetic systems

Contact Info

Product

Resources

About