Theoretical–experimental analysis of the heat transfer in a helical condenser for a heat transformer integrated to a water purification system. Issue 48 (20th October 2016)

• Record Type: Journal Article
• Authors: Hernández, A.H.; Flores, O.; Huicochea, A.; Álvarez, A.; Sierra, F.Z.; Silva, S.; Hernández, J.A.
• Is Part Of: Desalination and water treatment. Volume 57:Issue 48/49(2016)
• Page Start: 23132
• Page End: 23146
• Publication Date: 2016-10-20
• Subjects: Mathematical model of simple cell -- Nusselt number -- Carrol-water; Saline water conversion -- Periodicals; Saline water conversion; Water -- Purification; Periodicals; 628.167
• DOI: 10.1080/19443994.2015.1118886
• Languages: English
• ISSNs: 1944-3994

Abstract

Abstract: A theoretical–experimental analysis was carried out to acquire the coefficient of condensation heat transfer in a double-helical tube coupled to an absorption heat transformer, the last one operating with two working solutions (water and Carrol-water). In the condenser, the steam flows through the inner tube and the cooling water flows in countercurrent in the annular section. The condenser pressure is located within the ranges from 3.7 to 9.2 kPa with a Reynolds number of steam ranging from 6, 400 to 23, 500 for water and 6.1 to 9.2 kPa with a Reynolds number of steam ranging from 5, 550 and 22, 000 for the Carrol-water. The mass flux of the cooling water ranges from 450 to 850 kg/m 2 s and 750 to 1, 050 kg/m 2 s, respectively. Two methods are used for calculating the condensation heat transfer coefficient: the first considers the energy balance and heat transfer equations; and the second is by Wilson plot technique. The heat transfer coefficient results show similarity between both methods and ranges from 2, 400 W/m 2 °C ≤ α con ≤ 6, 100 W/m 2 °C and 810 W/m 2 °C ≤ α con ≤ 5, 650 W/m 2 °C, respectively. In addition, a mathematical model is applied using condensation coefficients obtained in the theoretical and experimental analysis. This model is given by algebraic and differential equations, obtaining satisfactory results in the energy flows. The equations were selected according to the phases and regime of the fluid to be condensed. Also a correlation for the condensation heat transfer coefficient based on the Nusselt, Reynolds, and Prandtl numbers for each of the two solutions is proposed. Finally, in the absorption heat transformer considering Carrol-water as a working fluid, it was possible to generate pure water in the water purification system.