SIAM Journal on Applied Mathematics, Volume 84, Issue 2, Page 621-631, April 2024. Abstract. DEM simulations by Chialvo et al. observed three distinct flow regimes for homogeneous simple shear of soft, frictional, noncohesive spheres in different domains of shear rate and density. This paper shows that all three regimes can be accommodated in a continuum description, using the CIDR formalism.
{"title":"Constitutive Relations for Granular Flow That Include the Three Flow Regimes of Chialvo et al.","authors":"David G. Schaeffer, Yuhao Hu","doi":"10.1137/23m1578097","DOIUrl":"https://doi.org/10.1137/23m1578097","url":null,"abstract":"SIAM Journal on Applied Mathematics, Volume 84, Issue 2, Page 621-631, April 2024. <br/> Abstract. DEM simulations by Chialvo et al. observed three distinct flow regimes for homogeneous simple shear of soft, frictional, noncohesive spheres in different domains of shear rate and density. This paper shows that all three regimes can be accommodated in a continuum description, using the CIDR formalism.","PeriodicalId":51149,"journal":{"name":"SIAM Journal on Applied Mathematics","volume":"168 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140593479","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Panagiotis Kaklamanos, Andrea Pugliese, Mattia Sensi, Sara Sottile
SIAM Journal on Applied Mathematics, Volume 84, Issue 2, Page 661-686, April 2024. Abstract. We propose a compartmental model for a disease with temporary immunity and secondary infections. From our assumptions on the parameters involved in the model, the system naturally evolves in three time scales. We characterize the equilibria of the system and analyze their stability. We find conditions for the existence of two endemic equilibria for some cases in which [math]. Then, we unravel the interplay of the three time scales, providing conditions to foresee whether the system evolves in all three scales, or only in the fast and the intermediate ones. We conclude with numerical simulations and bifurcation analysis to complement our analytical results.
{"title":"A Geometric Analysis of the SIRS Model with Secondary Infections","authors":"Panagiotis Kaklamanos, Andrea Pugliese, Mattia Sensi, Sara Sottile","doi":"10.1137/23m1565632","DOIUrl":"https://doi.org/10.1137/23m1565632","url":null,"abstract":"SIAM Journal on Applied Mathematics, Volume 84, Issue 2, Page 661-686, April 2024. <br/> Abstract. We propose a compartmental model for a disease with temporary immunity and secondary infections. From our assumptions on the parameters involved in the model, the system naturally evolves in three time scales. We characterize the equilibria of the system and analyze their stability. We find conditions for the existence of two endemic equilibria for some cases in which [math]. Then, we unravel the interplay of the three time scales, providing conditions to foresee whether the system evolves in all three scales, or only in the fast and the intermediate ones. We conclude with numerical simulations and bifurcation analysis to complement our analytical results.","PeriodicalId":51149,"journal":{"name":"SIAM Journal on Applied Mathematics","volume":"59 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140593192","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
SIAM Journal on Applied Mathematics, Volume 84, Issue 2, Page 632-660, April 2024. Abstract. In this paper, we are interested in the spatiotemporal pattern formations and bifurcations for a nondegenerate reaction-diffusion rabies SIR model which was used to explain the epidemiological patterns observed in Europe. First, by using the iteration methods, we are able to show the global existence and boundedness of in-time solutions of the parabolic system. Second, for the ODEs, we analytically prove the phenomena observed by Anderson et al. [Nature, 289 (1981), pp. 765–771]: if the carrying capacity [math] is smaller than some positive [math], then rabies eventually dies out; if [math] is larger than [math], then the rabies prevails. Moreover, if [math] for some positive [math], then the endemic equilibrium solution is (locally asymptotically) stable, while it is unstable if [math]. In particular, at [math], the loss of the stability of the endemic equilibrium leads to a Hopf bifurcation. Finally, for the PDEs, we derive sufficient conditions on the diffusion rates so that under these conditions, Turing instability of both the endemic equilibrium solution and the Hopf bifurcating spatially homogeneous periodic solutions can occur. Once Turing instability of the solution (equilibrium or periodic solution) occurs, it is observed numerically that the system might have new spatiotemporal patterns.
{"title":"Dynamics and Bifurcations in a Nondegenerate Homogeneous Diffusive SIR Rabies Model","authors":"Gaoyang She, Fengqi Yi","doi":"10.1137/23m159055x","DOIUrl":"https://doi.org/10.1137/23m159055x","url":null,"abstract":"SIAM Journal on Applied Mathematics, Volume 84, Issue 2, Page 632-660, April 2024. <br/> Abstract. In this paper, we are interested in the spatiotemporal pattern formations and bifurcations for a nondegenerate reaction-diffusion rabies SIR model which was used to explain the epidemiological patterns observed in Europe. First, by using the iteration methods, we are able to show the global existence and boundedness of in-time solutions of the parabolic system. Second, for the ODEs, we analytically prove the phenomena observed by Anderson et al. [Nature, 289 (1981), pp. 765–771]: if the carrying capacity [math] is smaller than some positive [math], then rabies eventually dies out; if [math] is larger than [math], then the rabies prevails. Moreover, if [math] for some positive [math], then the endemic equilibrium solution is (locally asymptotically) stable, while it is unstable if [math]. In particular, at [math], the loss of the stability of the endemic equilibrium leads to a Hopf bifurcation. Finally, for the PDEs, we derive sufficient conditions on the diffusion rates so that under these conditions, Turing instability of both the endemic equilibrium solution and the Hopf bifurcating spatially homogeneous periodic solutions can occur. Once Turing instability of the solution (equilibrium or periodic solution) occurs, it is observed numerically that the system might have new spatiotemporal patterns.","PeriodicalId":51149,"journal":{"name":"SIAM Journal on Applied Mathematics","volume":"48 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140593808","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
SIAM Journal on Applied Mathematics, Volume 84, Issue 2, Page 602-620, April 2024. Abstract. Cover times measure the speed of exhaustive searches which require the exploration of an entire spatial region(s). Applications include the immune system hunting pathogens, animals collecting food, robotic demining or cleaning, and computer search algorithms. Mathematically, a cover time is the first time a random searcher(s) comes within a specified “detection radius” of every point in the target region (often the entire spatial domain). Due to their many applications and their fundamental probabilistic importance, cover times have been extensively studied in the physics and probability literatures. This prior work has generally studied cover times of a single searcher with a vanishing detection radius or a large target region. This prior work has further claimed that cover times for multiple searchers can be estimated by a simple rescaling of the cover time of a single searcher. In this paper, we study cover times of many diffusive or subdiffusive searchers and show that prior estimates break down as the number of searchers grows. We prove a rather universal formula for all the moments of such cover times in the many searcher limit that depends only on (i) the searcher’s characteristic (sub)diffusivity and (ii) a certain geodesic distance between the searcher starting location(s) and the farthest point in the target. This formula is otherwise independent of the detection radius, space dimension, target size, and domain size. We illustrate our results in several examples and compare them to detailed stochastic simulations.
{"title":"Cover Times of Many Diffusive or Subdiffusive Searchers","authors":"Hyunjoong Kim, Sean D. Lawley","doi":"10.1137/23m1576645","DOIUrl":"https://doi.org/10.1137/23m1576645","url":null,"abstract":"SIAM Journal on Applied Mathematics, Volume 84, Issue 2, Page 602-620, April 2024. <br/> Abstract. Cover times measure the speed of exhaustive searches which require the exploration of an entire spatial region(s). Applications include the immune system hunting pathogens, animals collecting food, robotic demining or cleaning, and computer search algorithms. Mathematically, a cover time is the first time a random searcher(s) comes within a specified “detection radius” of every point in the target region (often the entire spatial domain). Due to their many applications and their fundamental probabilistic importance, cover times have been extensively studied in the physics and probability literatures. This prior work has generally studied cover times of a single searcher with a vanishing detection radius or a large target region. This prior work has further claimed that cover times for multiple searchers can be estimated by a simple rescaling of the cover time of a single searcher. In this paper, we study cover times of many diffusive or subdiffusive searchers and show that prior estimates break down as the number of searchers grows. We prove a rather universal formula for all the moments of such cover times in the many searcher limit that depends only on (i) the searcher’s characteristic (sub)diffusivity and (ii) a certain geodesic distance between the searcher starting location(s) and the farthest point in the target. This formula is otherwise independent of the detection radius, space dimension, target size, and domain size. We illustrate our results in several examples and compare them to detailed stochastic simulations.","PeriodicalId":51149,"journal":{"name":"SIAM Journal on Applied Mathematics","volume":"11 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140593465","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Giulia C. Fritis, Pavel S. Paz, Luis F. Lozano, Grigori Chapiro
SIAM Journal on Applied Mathematics, Volume 84, Issue 2, Page 581-601, April 2024. Abstract. Motivated by the foam displacement in porous media with linear adsorption, we extended the existing framework for two-phase flow containing an active tracer described by a non–strictly hyperbolic system of conservation laws. We solved the global Riemann problem by presenting possible wave sequences that composed this solution. Although the problems are well-posed for all Riemann data, there is a parameter region where the solution lacks structural stability. We verified that the model implemented on the most used commercial solver for geoscience, CMG-STARS, describing foam displacement in porous media with adsorption, satisfies the hypotheses to apply the developed theory, resulting in structural stability loss for some parameter regions.
{"title":"On the Riemann Problem for the Foam Displacement in Porous Media with Linear Adsorption","authors":"Giulia C. Fritis, Pavel S. Paz, Luis F. Lozano, Grigori Chapiro","doi":"10.1137/23m1566649","DOIUrl":"https://doi.org/10.1137/23m1566649","url":null,"abstract":"SIAM Journal on Applied Mathematics, Volume 84, Issue 2, Page 581-601, April 2024. <br/> Abstract. Motivated by the foam displacement in porous media with linear adsorption, we extended the existing framework for two-phase flow containing an active tracer described by a non–strictly hyperbolic system of conservation laws. We solved the global Riemann problem by presenting possible wave sequences that composed this solution. Although the problems are well-posed for all Riemann data, there is a parameter region where the solution lacks structural stability. We verified that the model implemented on the most used commercial solver for geoscience, CMG-STARS, describing foam displacement in porous media with adsorption, satisfies the hypotheses to apply the developed theory, resulting in structural stability loss for some parameter regions.","PeriodicalId":51149,"journal":{"name":"SIAM Journal on Applied Mathematics","volume":"32 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140325465","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
SIAM Journal on Applied Mathematics, Volume 84, Issue 2, Page 556-580, April 2024. Abstract. Phages are ubiquitous in nature, but many essential factors of host-phage biology have not yet been integrated into mathematical models. In this paper, we investigate a spatial phage-bacteria model to describe the propagation of phages and bacteria in different types of nutrient media. Unlike existing models, we construct a more realistic reaction-diffusion model that incorporates inoculum and bacterial growth and movement, then rigorous mathematical analysis is challenging. We study traveling wave solutions and obtain complete information about the existence and nonexistence of nontrivial traveling wave solutions. The threshold conditions for the existence and nonexistence of traveling wave solutions are obtained by using Schauder’s fixed point theorem, limiting argument, and one-sided Laplace transform. Considering different propagation media, we extend the existence of traveling wave solutions from liquid nutrition model to agar model. Moreover, in the absence of bacterial mortality, we obtain the existence of a new traveling wave solution describing phage invasion. We attempt to explain the occurrence of co-transport by the existence and nonexistence of traveling waves, and screen out the key parameters affecting the co-transport of phages and bacteria according to the definition of critical wave speed. Finally, we provide numerical simulations to verify the theoretical results and reveal the effects of key parameters on the propagation of phages and bacteria.
{"title":"Nontrivial Traveling Waves of Phage-Bacteria Models in Different Media Types","authors":"Zhenkun Wang, Hao Wang","doi":"10.1137/22m1505086","DOIUrl":"https://doi.org/10.1137/22m1505086","url":null,"abstract":"SIAM Journal on Applied Mathematics, Volume 84, Issue 2, Page 556-580, April 2024. <br/> Abstract. Phages are ubiquitous in nature, but many essential factors of host-phage biology have not yet been integrated into mathematical models. In this paper, we investigate a spatial phage-bacteria model to describe the propagation of phages and bacteria in different types of nutrient media. Unlike existing models, we construct a more realistic reaction-diffusion model that incorporates inoculum and bacterial growth and movement, then rigorous mathematical analysis is challenging. We study traveling wave solutions and obtain complete information about the existence and nonexistence of nontrivial traveling wave solutions. The threshold conditions for the existence and nonexistence of traveling wave solutions are obtained by using Schauder’s fixed point theorem, limiting argument, and one-sided Laplace transform. Considering different propagation media, we extend the existence of traveling wave solutions from liquid nutrition model to agar model. Moreover, in the absence of bacterial mortality, we obtain the existence of a new traveling wave solution describing phage invasion. We attempt to explain the occurrence of co-transport by the existence and nonexistence of traveling waves, and screen out the key parameters affecting the co-transport of phages and bacteria according to the definition of critical wave speed. Finally, we provide numerical simulations to verify the theoretical results and reveal the effects of key parameters on the propagation of phages and bacteria.","PeriodicalId":51149,"journal":{"name":"SIAM Journal on Applied Mathematics","volume":"31 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140325462","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
SIAM Journal on Applied Mathematics, Volume 84, Issue 2, Page 543-555, April 2024. Abstract. Considering the two-dimensional sloshing problem, our main focus is to construct domains with interior high spots; that is, points, where the free surface elevation for the fundamental eigenmode attains its critical values. The so-called semi-inverse procedure is applied for this purpose. The existence of high spots is proved rigorously for some domains. Many of the constructed domains have multiple interior high spots and all of them are bulbous at least on one side.
{"title":"Two-Dimensional Sloshing: Domains with Interior “High Spots”","authors":"Nikolay Kuznetsov, Oleg Motygin","doi":"10.1137/22m1541332","DOIUrl":"https://doi.org/10.1137/22m1541332","url":null,"abstract":"SIAM Journal on Applied Mathematics, Volume 84, Issue 2, Page 543-555, April 2024. <br/> Abstract. Considering the two-dimensional sloshing problem, our main focus is to construct domains with interior high spots; that is, points, where the free surface elevation for the fundamental eigenmode attains its critical values. The so-called semi-inverse procedure is applied for this purpose. The existence of high spots is proved rigorously for some domains. Many of the constructed domains have multiple interior high spots and all of them are bulbous at least on one side.","PeriodicalId":51149,"journal":{"name":"SIAM Journal on Applied Mathematics","volume":"67 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140302364","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
SIAM Journal on Applied Mathematics, Volume 84, Issue 2, Page 523-542, April 2024. Abstract. As summarized by Papageorgiou [Annu. Rev. Fluid Mech., 51 (2019), pp. 155–187], a strong normal electric field can cause instability of the interface in a hydrodynamic system. In the present work, singularities arising in electrocapillary-gravity waves on a dielectric fluid of finite depth due to an electric field imposed in the direction perpendicular to the undisturbed free surface are investigated. In shallow water, for a small-amplitude periodic disturbance in the linearly unstable regime, the outcome of the system evolution is that the gas-liquid interface touches the solid bottom boundary, causing a rupture. A quasi-linear hyperbolic model is derived for the long-wave limit and used to study the formation of the touch-down singularity. The theoretical predictions are compared with the fully nonlinear computations by a time-dependent conformal mapping for the electrified Euler equations, showing good agreement. On the other hand, a nonlinear dispersive model system is derived for the deep-water scenario, which predicts the blowup singularity (i.e., the wave amplitude tends to infinity in a finite time). However, when the fluid thickness is significantly large, one can numerically show the self-intersection nonphysical wave structure or 2/3 power cusp singularity in the full Euler equations.
{"title":"Singularities of Capillary-Gravity Waves on Dielectric Fluid Under Normal Electric Fields","authors":"Tao Gao, Zhan Wang, Demetrios Papageorgiou","doi":"10.1137/23m1575743","DOIUrl":"https://doi.org/10.1137/23m1575743","url":null,"abstract":"SIAM Journal on Applied Mathematics, Volume 84, Issue 2, Page 523-542, April 2024. <br/> Abstract. As summarized by Papageorgiou [Annu. Rev. Fluid Mech., 51 (2019), pp. 155–187], a strong normal electric field can cause instability of the interface in a hydrodynamic system. In the present work, singularities arising in electrocapillary-gravity waves on a dielectric fluid of finite depth due to an electric field imposed in the direction perpendicular to the undisturbed free surface are investigated. In shallow water, for a small-amplitude periodic disturbance in the linearly unstable regime, the outcome of the system evolution is that the gas-liquid interface touches the solid bottom boundary, causing a rupture. A quasi-linear hyperbolic model is derived for the long-wave limit and used to study the formation of the touch-down singularity. The theoretical predictions are compared with the fully nonlinear computations by a time-dependent conformal mapping for the electrified Euler equations, showing good agreement. On the other hand, a nonlinear dispersive model system is derived for the deep-water scenario, which predicts the blowup singularity (i.e., the wave amplitude tends to infinity in a finite time). However, when the fluid thickness is significantly large, one can numerically show the self-intersection nonphysical wave structure or 2/3 power cusp singularity in the full Euler equations.","PeriodicalId":51149,"journal":{"name":"SIAM Journal on Applied Mathematics","volume":"30 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140302377","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
SIAM Journal on Applied Mathematics, Volume 84, Issue 2, Page 477-496, April 2024. Abstract. Steady gravity-capillary periodic waves on the surface of a thin viscous liquid film supported by an air stream on an inclined wall are investigated. Based on lubrication approximation and thin air-foil theory, this problem is reduced to an integro-differential equation. The small-amplitude analysis is carried out to obtain two analytical solutions up to the second order. Numerical computation shows there exist two distinct primary bifurcation branches starting from infinitesimal waves, which approach solitary wave configuration in the long-wave limit when the values of physical parameters are above certain thresholds. New families of solutions manifest themselves either as secondary bifurcation occurring on primary branches or as isolated solution branches. The limiting configurations of the primary solution branches with the increase of two parameters are studied in two different cases, where one and two limiting configurations are obtained, respectively. For the latter case, the approximation of the configurations is given.
{"title":"Steady Wind-Generated Gravity-Capillary Waves on Viscous Liquid Film Flows","authors":"Y. Meng, D. T. Papageorgiou, J.-M. Vanden-Broeck","doi":"10.1137/23m1586318","DOIUrl":"https://doi.org/10.1137/23m1586318","url":null,"abstract":"SIAM Journal on Applied Mathematics, Volume 84, Issue 2, Page 477-496, April 2024. <br/> Abstract. Steady gravity-capillary periodic waves on the surface of a thin viscous liquid film supported by an air stream on an inclined wall are investigated. Based on lubrication approximation and thin air-foil theory, this problem is reduced to an integro-differential equation. The small-amplitude analysis is carried out to obtain two analytical solutions up to the second order. Numerical computation shows there exist two distinct primary bifurcation branches starting from infinitesimal waves, which approach solitary wave configuration in the long-wave limit when the values of physical parameters are above certain thresholds. New families of solutions manifest themselves either as secondary bifurcation occurring on primary branches or as isolated solution branches. The limiting configurations of the primary solution branches with the increase of two parameters are studied in two different cases, where one and two limiting configurations are obtained, respectively. For the latter case, the approximation of the configurations is given.","PeriodicalId":51149,"journal":{"name":"SIAM Journal on Applied Mathematics","volume":"22 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140202206","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jan Friedrich, Simone Göttlich, Alexander Keimer, Lukas Pflug
SIAM Journal on Applied Mathematics, Volume 84, Issue 2, Page 497-522, April 2024. Abstract. We consider conservation laws with nonlocal velocity and show, for nonlocal weights of exponential type, that the unique solutions converge in a weak or strong sense (dependent on the regularity of the velocity) to the entropy solution of the local conservation law when the nonlocal weight approaches a Dirac distribution. To this end, we first establish a uniform total variation bound on the nonlocal velocity, which can be used to pass to the limit in the weak solution. For the required entropy admissibility, we use a tailored entropy-flux pair and take advantage of a well-known result that a single strictly convex entropy-flux pair is sufficient for uniqueness, given some additional constraints on the velocity. For general weights, we show that the monotonicity of the initial datum is preserved over time, which enables us to prove convergence to the local entropy solution for rather general kernels if the initial datum is monotone. This case covers the archetypes of local conservation laws: shock waves and rarefactions. These results suggest that a “nonlocal in the velocity” approximation might be better suited to approximating local conservation laws than a nonlocal in the solution approximation, in which such monotonicity only holds for specific velocities.
{"title":"Conservation Laws with Nonlocal Velocity: The Singular Limit Problem","authors":"Jan Friedrich, Simone Göttlich, Alexander Keimer, Lukas Pflug","doi":"10.1137/22m1530471","DOIUrl":"https://doi.org/10.1137/22m1530471","url":null,"abstract":"SIAM Journal on Applied Mathematics, Volume 84, Issue 2, Page 497-522, April 2024. <br/> Abstract. We consider conservation laws with nonlocal velocity and show, for nonlocal weights of exponential type, that the unique solutions converge in a weak or strong sense (dependent on the regularity of the velocity) to the entropy solution of the local conservation law when the nonlocal weight approaches a Dirac distribution. To this end, we first establish a uniform total variation bound on the nonlocal velocity, which can be used to pass to the limit in the weak solution. For the required entropy admissibility, we use a tailored entropy-flux pair and take advantage of a well-known result that a single strictly convex entropy-flux pair is sufficient for uniqueness, given some additional constraints on the velocity. For general weights, we show that the monotonicity of the initial datum is preserved over time, which enables us to prove convergence to the local entropy solution for rather general kernels if the initial datum is monotone. This case covers the archetypes of local conservation laws: shock waves and rarefactions. These results suggest that a “nonlocal in the velocity” approximation might be better suited to approximating local conservation laws than a nonlocal in the solution approximation, in which such monotonicity only holds for specific velocities.","PeriodicalId":51149,"journal":{"name":"SIAM Journal on Applied Mathematics","volume":"181 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140202269","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}