# Energy system modelling with ASCEND

From ASCEND

This page will summarise the models that exist for energy system modelling using ASCEND.

- Combined-cycle gas turbine with a range of bottoming cycle working fluids.
- Rankine cycle: model of simple, reheat, regenerative and reheat-regenerative
**Rankine cycles**, including simple first-order component models of pumps, turbines, feedwater heaters, condensers and boilers. - Brayton cycle: models of simple, regenerative and regenerative intercooled
*Brayton cycles'*, using simple first-order components. - Data reader: system for reading weather data for use in dynamic simulations eg of solar energy systems.
- models/johnpye/thermalequilibrium2.a4c: dynamic model of heat transfer from superheated steam to subcooled water (needs updating to use current version of freesteam).
- models/heatex.a4c: detailed model of a condensing heat exchanger (uses CMSlv)
- models/pipeline.a4c: model of a pipe flow network including one-way check valves (uses CMSlv)
- Calculation of sun position
- Advection equation model, models/johnpye/advection.a4c
- Solar-thermal system modelling
- models/johnpye/moody.a4c: plotting a Moody (pipe friction) diagram using ASCEND (needs some external components, yet to be packaged)
- models/johnpye/radialheatloss.a4c: modelling of radial heat loss though pipe and insulation.
- models/johnpye/cavity.a4c: modelling of radiation balance in a cavity (by Radiosity method)
- FPROPS: calculation of properties of ammonia, water, hydrogen, nitrogen directly from Helmholtz functions.
- models/johnpye/simple_pv.a4c: model of a simple photovoltaic cell (thanks to Ioan-Alexandru Lazar)
- models/johnpye/exergy.a4c: simple demonstration of exergy destruction in mixing of two fluids.
- models/johnpye/datareader/testairprops.a4c: transport properties of air, read from a CSV file.