pocketORC: a browser-based calculator for teaching organic Rankine cycle power systems

This paper presents a steady-state design model for an organic Rankine cycle (ORC) power plant that is completely web-browser based and does not rely on any external libraries (e.g., for the computation of thermodynamic properties). This means the tool can be easily accessed by students via any electronic device with a web browser and used as a teaching aid to teach basic principles relating to ORC power systems. Therefore, ORC power cycles can be introduced interactively without requiring any programming knowledge or the distribution and installation of source files. This allows ORC power systems to be introduced earlier in the curriculum, and to a wider variety of students, than might otherwise be possible. The current version of the model combines the Peng-Robinson equation of state with a thermodynamic model of a recuperated ORC system and discretised heat exchanger sizing models. The model is written in the Python programming language and the PyScript framework is used to call Python code directly from HTML. The user can vary cycle variables such as the condensation temperature, pressure ratio, degree of superheat, recuperator effectiveness and heat-source temperature drop via the graphical-user interface which returns key indicators of cycle performance such as thermal efficiency and power output amongst others. The tool enables single-point calculation and parametric studies of a single variable and includes introductory self-paced lessons. This allows students to develop an understanding of the influence of different cycle variables on cycle performance. This paper provides an overview of the tool and its capabilities, alongside discussing its potential role as a teaching aid to support the introduction of ORC power systems into the curriculum.<p></p>