The Open Renewable Energy Journal

2009, 2 : 116-123
Published online 2009 November 23. DOI: 10.2174/1876387100902010116
Publisher ID: TOREJ-2-116

Instantaneous Determination of Heat Transfer Coefficients in a Steam Generator for an Alternative Energy Upgrade System

Sotsil Silva Soteloa , Rosenberg J. Romero and Roberto Best
Centro de Investigación en Ingeniería y Ciencias Aplicadas, Universidad Autónoma del Estado de Morelos, Av. Universidad 1001, Col. Chamilpa, C.P. 62209, Cuernavaca Morelos, México.

ABSTRACT

The present work shows a mathematical model to determine the thermal behavior of a steam generator in an alternative energy upgrade system. In this system, alternative energy (solar, geothermal or waste heat from an industrial process) is upgraded to a higher temperature, through a thermodynamic cycle. A plate heat exchanger is used as the steam generator, and is a key component in the system. A mixture of water-lithium bromide + ethylene glycol was used as working solution. The steam generator works with alternative energy, this is used to evaporate a part of the working solution inside the steam generator. The temperature profile and the heat transfer coefficients were obtained with type T thermocouples placed along the plate heat exchanger. The conditions that produce the highest heat transfer coefficients for the alternative energy system and the calculated heat transfer coefficients for the working solution are shown. This is the first work where a plate heat exchanger is used as a steam generator in an energy upgrade system and the first time that has been calculated the heat transfer coefficients for the working solution. There are no previous data of the use of the working solution on steam generators.

Keywords:

Alternative energy, heat transfer coefficients, temperature profile.