Initial-boundary value problems to semilinear multi-term fractional differential equations
arXiv:2301.07574 · doi:10.3934/cpaa.2023068
Abstract
For , we analyze the semilinear integro-differential equation on the one-dimensional domain in the unknown \[ \mathbf{D}_{t}^ν(\varrho_{0}u)+\sum_{i=1}^{M}\mathbf{D}_{t}^{ν_{i}}(\varrho_{i}u) -\sum_{j=1}^{N}\mathbf{D}_{t}^{μ_{j}}(γ_{j}u) -\mathcal{L}_{1}u-\mathcal{K}*\mathcal{L}_{2}u+f(u)=g(x,t), \] where are Caputo fractional derivatives, , , are uniform elliptic operators with time-dependent smooth coefficients, is a summable convolution kernel. Particular cases of this equation are the recently proposed advanced models of oxygen transport through capillaries. Under certain structural conditions on the nonlinearity and orders , the global existence and uniqueness of classical and strong solutions to the related initial-boundary value problems are established via the so-called continuation arguments method. The crucial point is searching suitable a priori estimates of the solution in the fractional Hölder and Sobolev spaces. The problems are also studied from the numerical point of view.