Abstract—An experimental study on combustion in porous media and thermoelectric generation was performed. The reactor was composed of two types of porous media where flame stabilization was reached at the interface of them. An external thermoelectric module was placed to harvest the thermal energy produced in the system. Maximum values of voltage and current obtained were 503 mV and 150 mA respectively. Index Terms—Energy conversion, super adiabatic combustion, thermoelectricity. I. INTRODUCTION Filtration combustion (FC) is generated when an incoming fuel/oxidizer mixture flows and reacts in the interstitial space of a porous matrix. Due to its better thermal properties, the porous material allows efficient redistribution of the energy released in the gas-phase chemical reaction [1]. In particular, energy feed-back from the hot products of combustion to the upstream region preheats the reagents and generates temperatures above the normal adiabatic limits for free flames. The excess of enthalpy generated allows sustained combustion for extremely low-calorie mixtures [2]-[4]. In the low-velocity regime of FC, classification given by [5] thermal and reaction waves propagates through the porous matrix at velocities of order 10 -4 m/s. Propagation of reaction wave may occur either downstream or upstream, as pointed by analytical relations [2], [3], [5]-[8], numerical simulations [9], [10] and demonstrated with experimental results [11]-[13]. Upstream wave propagation leads to temperatures under the normal adiabatic conditions, producing the so-called subadiabatic effect. Stationary waves (immovable relative to the porous medium), exhibit equilibrium temperatures equal to normal laminar flames. Downstream wave propagation produces equilibrium temperatures above the normal adiabatic ones, giving the superadiabatic effect. Combustion front displacement direction depends mainly on fuel equivalence ratio, combustion enthalpy and heat exchange between solid and gas phase. As a result, if heat generation on the front exceeds heat absorption by porous media internal surface, the combustion front displaces Manuscript received May 31, 2013; revised July 28, 2013. This work was supported by the by Conicyt-Chile under Fondecyt Grant 1131156 and 11100401. V. I. Bubnovich, L. A. Henríquez-Vargas, and F. E. Ibacache are with the Department of Chemical Engineering, University of Santiago of Chile, B. O’Higgins 3363, Santiago, Chile (e-mail: valeri.bubnovich@usach.cl, luis.henriquez@usach.cl, fibacaches@gmail. com). N. Orlovskaya is with the Department of Mechanical, Materials and Aerospace Engineering, University of Central Florida, Orlando, FL, USA (email: norlovsk@mail.ucf.edu ). against gas filtration. On the contrary, dealing with lean mixture or combustibles with low calorific power, the combustion front displaces downstream. Due to the unsteady nature of the FC phenomenon, confinement methods for the combustion front are necessary. From the alluded methods, it can be mentioned the reciprocal flow burner [14], [15], and stabilization based on the modified Peclet number for reactors with two sections of porous materials with different properties [7], [12], [16]. The use of thermoelectric elements to produce electricity as a direct conversion system from thermal energy provides several advantages: environmental friendliness, silent operation, no mechanical moving parts, no operating fluid employed, long life performance period [17]-[19]. However, the main drawback of the use of thermoelectric elements is its low conversion efficiency [20]. Thermoelectric generators operate by utilizing the Seebeck effect: a temperature difference across two jointed, but different, conducting materials will create a voltage. In order to further increase the voltage and power output, the temperature difference may be increased by increasing the hot-side temperature or decreasing the cool-side temperature across the device. Therefore, for a burner utilizing thermoelectric devices, the power generated can be maximized by increasing the combustion temperature, or by cooling the cool-side of the device through either passive means, like a heat-sink, or active means, like a fan or impinging air jet. It is standard to connect multiple thermoelectric devices together in series to increase the voltage and power outputs. Coupling of an efficient combustion system and a thermoelectric generator is an attractive alternative to bring power to areas where, due to its nature, no electrical connection to a power grid can be realized. Among the systems devised can be cited: the combustion-thermoelectric tube [21], the catalytic micro-combustor with integrated thermoelectric elements [22], the reciprocal flow thermoelectric porous burner. The latter has been studied both numerically [23], [24] and experimentally [25]. The present work focuses on thermoelectric generation using a porous media burner with flame stabilization at the interface of two porous bodies. II. SYSTEM DESCRIPTION Experimental Thermoelectric Generation in a Porous Media Burner Valeri I. Bubnovich, Nina Orlovskaya, Luis A. Henríquez-Vargas, and Francisco E. Ibacache 301 International Journal of Chemical Engineering and Applications, Vol. 4, No. 5, October 2013 The prototype reactor is composed of a rectangular steel casing (A36) to house there the porous sections with dimensions, 7×7 cm 2 outer square section, 25.4 cm length, 5.08 cm internal diameter, see Fig. 1. Two highly porous pure alumina (99.5 wt% Al 2 O 3 ) DOI: 10.7763/IJCEA.2013.V4.314