To establish the applicability of dimethyl ether (DME-CH3OCH3) as an alternative fuel additive to liquefied petroleum gas (LPG: 48% n-C4H10, 25% i-C4H10, 23% C3H10, 4% C2H6) for enhancing combustion and reducing hazardous emissions, in this article, the flame behavior of LPG-air mixture blended with DME is studied within a highly conducting and radiating porous inert burner (PIB) under excess enthalpy combustion conditions. The experiments are performed in a two section FIB comprising a silicon carbide (SiC) matrix and aluminum oxide (Al2O3) balls. The numerical model for solving the species continuity equation, energy balance equations for gas and solid phases, and the mass conservation equation is compared to the experimental data from the present work. New filtration velocity, data are found for the stable combustion of LPG-DME-air mixtures inside the PIB. The effect of various DME volume fractions in the LPG-DME blends on temperature distribution, radical pool concentration, CO emission, reaction zone thickness, and syngas production within the PIE are investigated. The results show that with the addition of DME the peak radical pool concentration increases, which enhances the filtration velocity and thus the operating limit of the PIB. It is further demonstrated that at the same input conditions, the solid-phase temperature and preheating temperature of the FIB are greater for the higher value of DME volume fraction. Contrary to previous findings, increasing the DME level increases the peak mole fraction of CO, CH4, and CH3CHO; however, it decreases the equilibrium CO concentration. Furthermore, in the case of a pure DME flame, an order of magnitude decrease in C2H2, C3H3, and C6H6 is observed; however, the flame with higher DME fraction generates more CH2O and CH3.