Parametric optimisation of the organic Rankine cycle for power generation from low-grade waste heat

This research work deals with the optimisation of controllable parameters of the organic Rankine cycle (ORC) run by waste heat. Performance measures have been evaluated for different waste heat temperatures, condenser temperatures, refrigerants and mass flow rate. The design of experiment was performed on the L9 orthogonal array of Taguchi's method. Three performance measures such as thermal efficiency, exergy destruction rate and the work output were used for the assessment and optimisation of the cycle. An optimum combination of parameters obtained by Taguchi's method is compared with analytical results. The comparison suggests that the variance of results is within the desired level of confidence. Individual effect of parameters on the performance of ORC is also estimated using analysis of variance. Turbine inlet temperature has large effects on efficiency and work output. Mass flow rate of the refrigerant has the largest effect on the exergy destruction rate.