Volume 6 Issue 1
A Theoretical-Experimental Comparison of an Improved Ammonia-Water Bubble Absorber by Means of a Helical Static Mixer
Jesús Cerezo, Roberto Best, Jorge Jesús Chan, Rosenberg J. Romero, Jorge I. Hernandez and Fernando Lara
1Centro de Investigación en Ingeniería y Ciencias Aplicadas, Universidad Autónoma del Estado de Morelos, Av. Universidad 1001, Cuernavaca 62209, Morelos, Mexico
2Instituto de Energías Renovables, Universidad Nacional Autónoma de México, Temixco 62580, Morelos, Mexico
3Universidad Autónoma de Campeche, Av. Agustín Melgar s/n, Buenavista 24030, Campeche, Mexico
4Facultad de Ingeniería, Universidad Autónoma de Baja California, Blvd. Benito Juárez y Calle de la Normal s/n, Insurgentes Este, Mexicali 21280, Baja California, Mexico
*Author to whom correspondence should be addressed
Abstract
The heat transfer in double pipe heat exchangers is very poor. This complicates its application in absorption cooling systems, however, the implementation of simple passive techniques should help to increase the heat and mass transfer mainly in the absorber. This paper carried out a simulation and its experimental comparison of a NH3-H2O bubble absorption process using a double tube heat exchanger with a helical screw static mixer in both central and annular sides. The experimental results showed that the absorption heat load per area is 31.61% higher with the helical screw mixer than the smooth tube. The theoretical and experimental comparison showed that the absorption heat load difference values were 28.0 and 21.9% for smooth tube and the helical mixer, respectively. These difference values were caused by the calculation of the log mean temperature difference in equilibrium conditions to avoid the overlap of solution temperatures. Therefore, the theoretical and experimental results should be improved when the absorption heat is included in the heat transfer equation or avoiding the operation condition when output is lower than input solution temperature.
Keywords:absorber; ammonia-water; helical screw static mixer; double pipe