Thermodynamic study of ORC at different working and peripheral conditions
Session: Poster session & Welcome drinks
Session starts: Wednesday 13 September, 17:30
Talieh Rajabloo ()
Organic Rankine cycles (ORC) are suitable for conversion of low temperature heat to electric power. Operation of ORC is based on the same principles as that of a steam Rankine cycle, but, differs from the latter in the usage of low-boiling-point organic fluids as a working fluid .
Furthermore, different environmental conditions beside hot source changes affect ORC performance. Thus, off-design analysis is necessary to find performance of the cycle at various peripheral conditions.
This project is conducted based on a previous study  in which the on-design results of ORC were obtained for pure and mixture working fluids. Besides, pool boiler was, suggested as a new approach to evaporator for the binary mixture, however, it is not the subject of this study at off-design conditions. Therefore, referring to the on-design results of low temperature ORC from previous model , off-design analysis of the cycle with shell and tube evaporator is conducted in ASPEN PLUS environment.
The goal of this study was to provide a system design that meets the process requirements at various peripheral conditions while providing reliable operation. Results showed that higher hot source duty and heat rejection lead to better cycle performance. Moreover, a primary study on the effect of thermal decomposition of working fluid is considered in this study.
To sum up, although a proper selection of mixtures of working fluid can help performance of the cycle, the heat exchanger type, peripheral conditions and properties of working fluid can, strongly, affect the performance of the ORC.
The author gratefully acknowledge the guidelines of professors Costante M. Invernizzi and Paolo Iora from University of Brescia, beside prof. Davide Bonalumi from polytechnic university of Milan.
1. P. Bombarda, et al., Applied Thermal Engineering, 2009. 30: 212-219.
2. T. Rajabloo, et al., Applied Thermal Engineering, 2016. 98: 1-9.