TY - JOUR ID - Abdelouahab2024 LB - Abdelouahab2024 AU - Abdelouahab, Ahlem AU - Bensid, Sabri TI - Analysis of a multiphase free boundary problem ST - Analysis of a multiphase free boundary problem JO - Opuscula Math. JA - Opuscula Math. JF - Opuscula Mathematica PY - 2024 VL - 44 IS - 5 SP - 631 EP - 649 DO - https://doi.org/10.7494/OpMath.2024.44.5.631 UR - https://doi.org/10.7494/OpMath.2024.44.5.631 AB - In this paper, we investigate a free boundary problem relevant in several applications, such as tumor growth models. Our problem is expressed as an elliptic equation involving discontinuous nonlinearities in a specified domain with a moving boundary. We establish the existence and uniqueness of solutions and provide a qualitative analysis of the free boundaries generated by the nonlinear term (inner boundaries). Furthermore, we analyze the dynamics of the outer region boundary. The final result demonstrates that under certain conditions, our problem is solvable in the neighborhood of a radial solution. KW - discontinuous nonlinearity KW - free boundary KW - perturbation KW - tumor growth SN - 1232-9274 ER -