Journal Pre-proof Solution of generalized Riemann problem for hyperbolic πβsystem with damping Rahul Kumar Chaturvedi, Pooja Gupta, L.P. Singh
PII: DOI: Reference:
S0020-7462(19)30301-4 https://doi.org/10.1016/j.ijnonlinmec.2019.07.014 NLM 3229
To appear in:
International Journal of Non-Linear Mechanics
Received date : 2 May 2019 Revised date : 24 July 2019 Accepted date : 25 July 2019 Please cite this article as: R.K. Chaturvedi, P. Gupta and L.P. Singh, Solution of generalized Riemann problem for hyperbolic πβsystem with damping, International Journal of Non-Linear Mechanics (2019), doi: https://doi.org/10.1016/j.ijnonlinmec.2019.07.014. This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. Β© 2019 Published by Elsevier Ltd.
Journal Pre-proof
Solution of generalized Riemann problem for hyperbolic πβsystem with damping
Rahul Kumar Chaturvedia,β, , Pooja Guptaa and L P Singha a Department
India.
of Mathematical Sciences, Indian Institute of Technology, Banaras Hindu University, Varanasi 221005,
ABSTRACT
Keywords: Hyperbolic system Generalized Riemann problem Exact solutions Differential constraint method
The aim of this paper is to determine the exact solution of the generalized Riemann problem for the 2 Γ 2 hyperbolic πβsystem with linear damping. Differential constraint method is used to find the solution of the system of governing equations. Also, consistency conditions and constraint equations for the hyperbolic system are obtained. Further, we solve the generalized Riemann problem of non-homogeneous hyperbolic πβsystem which involves discontinuous initial data.
re-
pro
of
ARTICLE INFO
1. Introduction
urn al P
In the present paper, we consider the model, hyperbolic πβsystem with linear damping and determine the exact solution of generalized Riemann problem using differential constraint method. The governing equations describing the hyperbolic πβsystem with linear damping of a compressible flow, in the Lagrangian coordinate is given by [1, 2] { ππ‘ β π£π₯ = 0, (1) π£π‘ + π(π)π₯ = βπΌπ£,
Jo
where (π₯, π‘) β π
Γ π
+ . π₯ and π‘, respectively, represent space and time coordinates. π£(π₯, π‘) and π(π₯, π‘) > 0 are the velocity and the specific volume respectively. The function π(π) (pressure) is the smooth function such that π(π) > 0 and πβ² (π) < 0. The term βπΌπ£ which appears in the momentum equation represents a linear damping with πΌ > 0. In the present paper, we consider a particular case that the pressure π is given by a πΎ-law with πΎ=1 as [3, 4] π(π) = π1 . The system (1) is considered by several authors in past decades and various results have been examined. The authors Mei [1, 5], Nishihara [2] etc. have discussed the behavior of solution of system (1). In the present paper we use the method of differential constraints to obtain the exact solution of generalized Riemann problem for the hyperbolic system (1). In past decades several types of mathematical methods have been used to obtain the exact or approximate analytical solution of the system of PDEs. For example, perturbation method, similarity method, differential constraints method etc.. Among these methods the differential constraints method is of great interest because β Corresponding
author
[email protected] (R.K. Chaturvedi) ORCID (s):
RK Chaturvedi et al.: Preprint submitted to Elsevier
Page 1 of 8
Journal Pre-proof
urn al P
re-
pro
of
of its systematic procedure to find the exact solution of hyperbolic system of PDEs. This method is applicable to the system of PDEs and it was first used by Janenko [6] in the gasdynamics regime. Curro et al. [7, 8, 9] have discussed the exact solutions of non-homogeneous and homogeneous 2Γ2 hyperbolic system using differential constraints method. The exact solution describing soliton-like interaction in a non dispersive medium is obtained by Seymour and Varley [10]. Further, C. Curro et al. [11, 12] have studied the exact description of simple wave for multicomponent hyperbolic system. Within this theoretical framework, differential constraint method is used for solving generalized Riemann problem for hyperbolic πβsystem with linear damping. In recent years, Curro et al. [13, 14, 15], Manganaro [16], Sahoo et al. [17] have discussed the solution of Riemann problem as well as generalized Riemann problem for hyperbolic balance law. Chaiyasena et al. [18] have studied the generalized Riemann problem and their adjoinment through a shock wave. Shekhar et al. [19], Singh et al. [20], Kuila et al. [21], Gupta et al. [22] have studied the classical Riemann problem for several relevant cases. The study of generalized Riemann problem (GRP) involves complexities and requires more attentions. Since the analytical expressions for the exact or approximate solution of GRP, in the case of quasilinear hyperbolic system, are usually not available. In order to find the solution of GRP, authors have used this method for several models like πβsystem with relaxation ([23]), rate-type material ([17]), fast diffusion equations ([24]), traffic flow model ([13, 14]), ET6 model ([25]), non-linear transmission lines ([15]), non-linear diffusion-convention equations ([26]) etc. The rest of the paper is organized as: section 2 contains the procedure of the method to find the exact solution of system (1). section 3 contains the brief analysis of model taken in this paper. Section 4 sketches the phenomenon of GRP and the exact solution of GRP is obtained. In last section 5, we discuss the results and conclusions of the problem. 2. Differential constraint method
In this section for our convenience, we discuss the important steps of differential constraint method, described by Curro et al. [23], which will be helpful to obtain the solution of system (1). We consider the one-dimensional hyperbolic system of quasilinear PDEs ππ‘ + π(π )ππ₯ = π(π ),
(2)
Jo
where π β π
π , π(π ) and π(π ) are column vectors representing field variables, the coefficient matrix and column vector representing source terms respectively. Since the system (2) is hyperbolic in nature, therefore the matrix ππΓπ has π real eigenvalues π(π) , π = 1, 2, ....π., and corresponding to each eigenvalues π(π) we have π linearly independent left eigenvectors πΏ(π) and π right eigenvectors π
(π) . Let us consider that the system (2) is strictly hyperbolic system i.e. π(π) β π(π) , βπ, π = 1, 2, ...π, π β π. Let us assume that { 0 if π β π, (π) (π) πΏ .π
= (3) 1 if π = π. We append the set of π β 1 differential constraints of first order as [15] πΏ(π) β
ππ₯ = π(π) (π₯, π‘, π ),
π = 1, 2, ....., π β 1,
RK Chaturvedi et al.: Preprint submitted to Elsevier
(4) Page 2 of 8
Journal Pre-proof where the function π(π) is an unspecified function which will be determined during the reduction process. The consistency conditions for the arbitrary function π(π) can be determined from (2) and (4), given as +π +
(π)
π(π) π₯
ββ πβ1 πβ1
+
πβ1 β
( ) π(π) πΏ(π) (βπ
(π) π β βππ
(π) ) + π(π) βπ(π) π
(π)
π=1
(
π(π) π(π) (π(π) β π(π) )πΏ(π) βπ
(π) π
(π) + βπ(π)
πβ
(π)
(5)
) π(π) (π(π) β π(π) )π
(π)
= 0,
π=1
(π)
(π)
(π β π )βπ π
(π)
+
πβ1 β
pro
π=1 π=1
πβ1 β
of
ππ‘(π)
π(π) (π(π) β π(π) )πΏ(π) (βπ
(π) π
(π) β βπ
(π) π
(π) )
π=1
(6)
+ πΏ(π) (π
(π) π β βππ
(π) ) + π(π) βπ(π) π
(π) = 0,
(π)
urn al P
re-
where β = πβππ , π = 1, 2, ...π β 1. Once the function π(π) satisfies the consistency conditions (5) and (6), the systems (2) and (4) become compatible. Then we can obtain a class of exact solution of the given system of governing PDEs by direct integration of overdetermined system (2) and (4). The overdetermined constraint equations and consistency conditions help to rewrite the original system in to a partial decoupled form so that we can solve it and obtain exact solution which satisfies the original system and constraint equations. The reduced system is written in the following form ππ‘ + π ππ₯ = π +
πβ1 β
( ) π(π) π(π) β π(π) π
(π) .
(7)
π=1
Jo
Once π(π) satisfies the consistency conditions, the solution of the systems (2), (4) can be obtained by direct integration of the equations (7) along with the constraint equations (4). Furthermore since the constraint equations (4) are involutive, they will characterize the set of initial conditions compatible with the class of solution under interest. Also, it is noticeable from (2) and (4) that when the source term π(π ) = 0 and π(π) = 0, system (7) results in a classical wave solution to a hyperbolic system. Therefore, the obtained solution of (2) characterized by (7) generalizes the simple wave of the homogeneous case taking into account source-like effects in hyperbolic wave process. For more details one may refer [8, 13, 15, 23]. 3. Exact solution
In this section, we use the above mentioned method to obtain the exact solution of the hyperbolic system (1) describing πβsystem with linear damping. The system (1) can be written in the form of (2), where [ ] [ ] [ ] π 0 β1 0 π= , π(π ) = β² , π(π ) = . (8) π£ π (π) 0 βπΌπ£ RK Chaturvedi et al.: Preprint submitted to Elsevier
Page 3 of 8
Journal Pre-proof
where π0 = Β±1. and corresponding eigenvectors are
[
1 β 2 βπβ² (π) 1 2
]
, π
(2) =
pro
πΏ(1)
] [ β ] [β (2) β² β² = βπ (π) 1 , πΏ = β βπ (π) 1 , π
(1) =
of
Consider π(π) , π = 1, 2 are eigenvalues of the coefficient matrix π2Γ2 , π
(π) and πΏ(π) are the right and left eigenvectors of the corresponding eigenvalues, π(π) , π = 1, 2, defined as β β π(2) = βπβ² (π) π(1) = β βπβ² (π), which can be written as β (π) π = π0 βπβ² (π), (9)
[
β
1 β 2 βπβ² (π) 1 2
]
, (10)
respectively. From equation (4), the required differential constraint associated to the system (1) can be written in the form π£π₯ + π(π)ππ₯ = π(π₯, π‘, π, π£).
(11)
re-
Substituting equations (8), (9), (10) and (11) in the consistency conditions (5) and (6), we obtain the following consistency equations
ππ + πππ£ = β
urn al P
ππ‘ + πππ₯ β πΌπ£ππ£ + π(πππ£ + ππ ) = βπΌπ, 1 (ππΌ + πβ² π), 2π
(12) (13)
where the prime denotes the differentiation. Once π(π₯, π‘, π, π£) is obtained by (12) and (13), from (7) we obtain the solution of the system (1) and (11) by integrating the following set of constraints along with (11) { ππ‘ + πππ₯ = π, (14) π£π‘ + ππ£π₯ = β(πΌπ£ + ππ).
Prior to determine the exact solution of the system (14), we determine the arbitrary function π(π₯, π‘, π, π£) from the consistency equations (12) and (13). On integrating (13), we obtain the following general solution of (13)
Jo
π = βπΌπ + π1β2 π(π₯, π‘, π),
(15)
where π = π£ β π0 log π and π(π₯, π‘, π) is an arbitrary function. Next the substitution of (15) into (12) yields πΌ 1 ππ‘ + πππ₯ β πΌπ£ππ β πβ1β2 π2 β π = 0. 2 2
(16)
The last step of the process is to determine π(π₯, π‘, π) which satisfies (16) for all π. It is noticeable that π = 0 must satisfy the above equation (16) for all π which implies that π = 0 must be a solution RK Chaturvedi et al.: Preprint submitted to Elsevier
Page 4 of 8
Journal Pre-proof
of
of equation (16). On the insertion in (15), we find that π = βπΌπ. Now we look for a special solution of the compatibility conditions (12) and (13) under the form π = π(π). On substituting it in (12) and (13), and solving the resulting equations we obtain that π = βπΌπ is the solution of the consistency conditions (12) and (13) as well as π(π) = π1 βπ + π2 , where π1 and π2 are arbitrary constants. Substituting this to the system (14) specialize to { ππ‘ + πππ₯ = βπΌπ, (17) π£π‘ + ππ£π₯ = βπΌπ£ + ππΌπ. along with (11)
pro
π£π₯ + π(π)ππ₯ = βπΌπ.
(18)
β§ βπΌπ‘ βͺπ(π§, π‘) = π0 (π§)π , βͺπ£(π§, π‘) = π£0 (π§)πβπΌπ‘ + π0 (1 β πβπΌπ‘ ), β¨ βͺπ§ = π₯ + π0 (1 β ππΌπ‘ ) . βͺ πΌπ0 β©
re-
Now, we integrate the system (18) with initial data π(π₯, 0) = π0 (π₯) and π£(π₯, 0) = π£0 (π₯) gives the following solution of the system (1)
(19)
urn al P
Within the context of differential constraint method, we have obtained the solution (19) of the system (1) for arbitrary initial data π0 (π₯) and π£0 (π₯). Now we are interested to introduce the initial conditions in the next section which are known as GRP. In next section we solve the GRP to determine the exact solution for the model (1). 4. Generalized Riemann problem
The purpose of this section is to discuss how the differential constraint method helps to solve the generalized Riemann problem of interest in 2 Γ 2 hyperbolic πβsystem with damping. The generalized Riemann problem for the system (1) with the initial data can be written as { (ππ (π₯), π£π (π₯)), for π₯ < 0, π (π₯, 0) = (20) (ππ (π₯), π£π (π₯)), for π₯ > 0,
Jo
where ππ (π₯), π£π (π₯), ππ (π₯) and π£π (π₯) are arbitrary functions. We set ππΏ = limβ ππ (π₯), π₯βΆ0
π£πΏ = limβ π£π (π₯),
ππ
= lim+ ππ (π₯), π₯βΆ0
π£π
= lim+ π£π (π₯), π₯βΆ0
π₯βΆ0
(21)
where ππΏ β ππ
and π£πΏ β π£π
. In order to solve the GRP (20), we consider the solution (20) and substitute this into the constraint (18) which gives the following constraint equation for the initial conditions ππ0 (π§) ππ£0 (π§) + π0 πβ1 = βπΌπ0 (π§). 0 ππ§ ππ§
RK Chaturvedi et al.: Preprint submitted to Elsevier
(22) Page 5 of 8
Journal Pre-proof According to method of differential constraints, the initial data (20) satisfies the constraint equation (22). Then on integrating (22) along with the initial data (20) yields the following implicit forms π₯ β§π£ (π₯) = π£ (π₯) β π (ln π (π₯) β ln π ) β πΌ π (π)ππ, πΏ 0 π πΏ βͺ π β«0 π π₯ β¨ ( ) βͺπ£π (π₯) = π£π
(π₯) β π0 ln ππ (π₯) β ln ππ
β πΌ π (π)ππ, β© β«0 π
(23)
re-
along with ) π ( π§ = π₯ + πΌπ0 1 β ππΌπ‘ . π Case II- For π₯ > 0, we get { π(π§, π‘) = ππ (π§)πβπΌπ‘ , π£(π§, π‘) = π£π (π§)πβπΌπ‘ β π0 (1 β πβπΌπ‘ ),
pro
of
Now we characterize the solution (19) to solve the governing system (1) along with (20). Case I- For π₯ < 0, we get { π(π§, π‘) = ππ (π§)πβπΌπ‘ , π£(π§, π‘) = π£π (π§)πβπΌπ‘ β π0 (1 β πβπΌπ‘ ),
(24)
(25)
π₯π (π‘) =
urn al P
along with ) π ( π§ = π₯ + πΌπ0 1 β ππΌπ‘ . π Since π£π (π₯) and π£π (π₯) are given by (23) and we obtain that π§ = π₯ at π‘ = 0. Therefore the solution (24) exists for π§ < 0, i.e. π₯ < π₯π (π‘), where ) π0 ( πΌπ‘ π β1 . πΌππ
(26)
) π0 ( πΌπ‘ π β1 . πΌππ
(27)
Similarly, the solution (25) exists for π₯ > π₯π (π‘), where π₯π (π‘) =
In order to connect smoothly the left state (24) to the right state (25), we integrate the differential constraints (17) subject to the following initial conditions
Jo
π₯(0) = 0, π = π(π), π£ = π (π), β π β [0, 1], π(0) = ππΏ , π(1) = ππ
, π (0) = π£πΏ , π (1) = π£π
.
(28)
Then the solutions are
β§ βπΌπ‘ βͺπ(π₯, π‘) = π(π)π , ( ) βͺπ£(π₯, π‘) = π (π)πβπΌπ‘ β π0 1 β πβπΌπ‘ , β¨ βͺπ₯ = β π0 (ππΌπ‘ β 1) . βͺ πΌπ(π) β© RK Chaturvedi et al.: Preprint submitted to Elsevier
(29)
Page 6 of 8
Journal Pre-proof On substitution of (29) in (18), yields (30)
π β² = π0 π β1 π β² . On integrating (30) along the conditions (28), we get ( ) π (π) = π£πΏ + π0 ln π(π) β ln ππΏ ,
(31)
of
along with π£πΏ β π0 ln ππΏ = π£π
β π0 ln ππ
.
(32)
re-
pro
Now, in order to confirm the existence of the solution (29), we need ππβππ > 0 which implies that ππΏ > ππ
if π0 = 1 and ππΏ < ππ
if π0 = β1. Therefore the central state (29) exists in the region π₯π (π‘) β€ π₯(π‘) β€ π₯π and it connects the left state (26) with right state (27) provided that the condition (32) is satisfied. On eliminating π(π) from (29)1 and (29)3 and substituting (31) in (29)2 yields the required result { ) π ( π(π₯, π‘) = πΌπ₯0 πβπΌπ‘ β 1 , )) ( ( (33) π£(π₯, π‘) = π£πΏ + π0 ln π(π) β ln ππΏ πβπΌπ‘ β πΌπ₯π(π)πβπΌπ‘ ,
5. Conclusion
urn al P
) π ( where π(π) = πΌπ₯0 1 β ππΌπ‘ . Equation (33) is required solution of GRP for the governing system (1). In the present work, we consider the hyperbolic system of first order PDEs describing πβsystem with linear damping and use differential constraint method to characterize the solution of this model. Within the framework of this method, we have obtained the consistency conditions for the governing model. Compatibility of the solution of the constraint equation and governing system is also discussed. The solution of the governing model is obtained in section 3 which is characterized for an arbitrary function as initial data to determine the exact solution for generalized Riemann problem. The solution obtained for the GRP consists of two states; left state and right state which are connected smoothly by the solution. This solution describes the rarefaction wave of the homogeneous case. 6. Acknowledgments
References
Jo
The authors are grateful to the referee for the valuable suggestions and comments to improve the quality of the manuscript. [1] M. Mei, Best asymptotic profile for hyperbolic p-system with damping, SIAM Journal on Mathematical Analysis 42 (1) (2010) 1β23. [2] K. Nishihara, T. Yang, Boundary effect on asymptotic behaviour of solutions to the p-system with linear damping, journal of differential equations 156 (2) (1999) 439β458. [3] T. Luo, R. Natalini, T. Yang, Global bv solutions to a p-system with relaxation, Journal of Differential Equations 162 (1) (2000) 174β198. [4] T. Yang, C. Zhu, Existence and non-existence of global smooth solutions for p-system with relaxation, Journal of Differential Equations 161 (2) (2000) 321β336.
RK Chaturvedi et al.: Preprint submitted to Elsevier
Page 7 of 8
Journal Pre-proof
Jo
urn al P
re-
pro
of
[5] M. Mei, Nonlinear diffusion waves for hyperbolic p-system with nonlinear damping, Journal of Differential Equations 247 (4) (2009) 1275β 1296. [6] N. Janenko, Compatibility theory and methods of integration of systems of nonlinear partial differential equation, Proc. of the Fourth All-Union Math. Cong.(Leningrad) (1964) 247β252. [7] C. CurrΓ², D. Fusco, N. Manganaro, An exact description of nonlinear wave interaction processes ruled by 2 Γ 2 hyperbolic systems, Zeitschrift fΓΌr angewandte Mathematik und Physik 64 (4) (2013) 1227β1248. [8] C. CurrΓ³, D. Fusco, N. Manganaro, Hodograph transformation and differential constraints for wave solutions to 2Γ 2 quasilinear hyperbolic nonhomogeneous systems, Journal of Physics A: Mathematical and Theoretical 45 (19) (2012) 195207. [9] C. CurrΓ², D. Fusco, On a class of quasilinear hyperbolic reducible systems allowing for special wave interactions, Zeitschrift fΓΌr angewandte Mathematik und Physik ZAMP 38 (4) (1987) 580β594. [10] B. Seymour, E. Varley, Exact solutions describing soliton-like interactions in a nondispersive medium, SIAM Journal on Applied Mathematics 42 (4) (1982) 804β821. arXiv:https://doi.org/10.1137/0142056, doi:10.1137/0142056. URL https://doi.org/10.1137/0142056 [11] C. CurrΓ³, D. Fusco, N. Manganaro, Exact description of simple wave interactions in multicomponent chromatography, Journal of Physics A: Mathematical and Theoretical 48 (1) (2014) 015201. [12] C. CurrΓ³, N. Manganaro, M. V. Pavlov, Nonlinear wave interaction problems in the three-dimensional case, Nonlinearity 30 (1) (2016) 207β 224. doi:10.1088/1361-6544/30/1/207. URL https://doi.org/10.1088%2F1361-6544%2F30%2F1%2F207 [13] C. CurrΓ³, D. Fusco, N. Manganaro, Differential constraints and exact solution to riemann problems for a traffic flow model, Acta applicandae mathematicae 122 (1) (2012) 167β178. [14] C. CurrΓ³, N. Manganaro, Riemann problems and exact solutions to a traffic flow model, Journal of Mathematical Physics 54 (7) (2013) 071503. [15] C. Curro, D. Fusco, N. Manganaro, A reduction procedure for generalized riemann problems with application to nonlinear transmission lines, Journal of Physics A: Mathematical and Theoretical 44 (33) (2011) 335205. [16] N. Manganaro, Riemann problems for viscoelastic media, Rendiconti Lincei-Matematica e Applicazioni 28 (3) (2017) 479β495. [17] S. M. Sahoo, T. R. Sekhar, G. R. Sekhar, Exact solutions of generalized riemann problem for rate-type material, International Journal of Non-Linear Mechanics 110 (2019) 16β20. [18] A. Chaiyasena, W. Worapitpong, S. Meleshko, Generalized riemann waves and their adjoinment through a shock wave, Mathematical Modelling of Natural Phenomena 13 (2) (2018) 22. [19] T. R. Sekhar, V. Sharma, Riemann problem and elementary wave interactions in isentropic magnetogasdynamics, Nonlinear Analysis: Real World Applications 11 (2) (2010) 619β636. [20] R. Singh, L. Singh, Solution of the riemann problem in magnetogasdynamics, International Journal of Non-Linear Mechanics 67 (2014) 326β330. [21] S. Kuila, T. R. Sekhar, Riemann solution for one dimensional non-ideal isentropic magnetogasdynamics, Computational and Applied Mathematics 35 (1) (2016) 119β133. [22] P. Gupta, L. Singh, R. Singh, Riemann problem for non-ideal polytropic magnetogasdynamic flow, International Journal of Non-Linear Mechanics. [23] C. CurrΓ³, N. Manganaro, Generalized riemann problems and exact solutions for p-systems with relaxation, Ricerche di Matematica 65 (2) (2016) 549β562. [24] O. V. Kaptsov, I. V. Verevkin, Differential constraints and exact solutions of nonlinear diffusion equations, Journal of Physics A: Mathematical and General 36 (5) (2003) 1401. [25] C. CurrΓ³, N. Manganaro, Differential constraints and exact solutions for the et6 model, Ricerche di Matematica 68 (1) (2019) 179β193. [26] M. Edwards, P. Broadbridge, Exact transient solutions to nonlinear diffusion-convection equations in higher dimensions, Journal of Physics A: Mathematical and General 27 (16) (1994) 5455.
RK Chaturvedi et al.: Preprint submitted to Elsevier
Page 8 of 8
Journal Pre-proof Highlights A generalized Riemann problem for 2x2 hyperbolic system with damping is analyzed.
ο·
Differential constraint method is used to obtain the exact solution of hyperbolic p-system.
ο·
A generalized Riemann data is taken as discontinuous initial condition.
ο·
Exact solution of generalized Riemann problem is obtained.
ο·
Behavior of solution profiles of generalized Riemann problem is discussed.
Jo
urn al P
re-
pro
of
ο·