Can Ozgur Colpan

Thermal Modelling of a Plate-Type Heat Exchanger-Based Biomass-Fired Regenerative Organic Rankine Cycle

Heat generated from the combustion of biomass can be used as an energy source in an organic Rankine cycle (ORC). In this paper, a thermal model of an integrated biomass-fired regenerative ORC system is formed. To model the heat exchangers, a discretization scheme is used that includes the phase change within a segment. Energy balances are applied to the turbine and the pump. The ORC model developed for is validated with experimental data of an existing ORC system. Then, the effect of biomass type on the performance of the system (i.e. the net power output and the thermal efficiency) is investigated.

Thermodynamic optimisation of a hybrid solar-geothermal power plant using Taguchi method

In this paper, an exergetic optimisation of a hybrid solar-geothermal power plant based on Taguchi method is presented. The effects of ambient temperature and solar irradiance on the output parameters of the system were first studied using a thermal model. Then, an optimisation study based on Taguchi method was performed to find the values of the key design and operating parameters that maximises the net power output and the electrical and exergetic efficiencies of the system. The results of this study showed that when the solar irradiance increases, the net power output and the exergetic and electrical efficiencies increase. It was also shown that the turbine inlet and exit pressures are the most dominant factors affecting the performance of the system. In addition, the net power output and the electrical and exergetic efficiencies can be increased up to 16,773 kW, 21.63%, and 70.06%, respectively, for the case study conducted.

Investigating the Effect of Different Refrigerants on the Performance of a Supercritical Organic Rankine Cycle

In this study, effect of different working fluid on the performance of an existing geothermal power plant located in Aydin, Turkey is investigated. The geothermal fluid is produced at a temperature of 178 °C and a pressure of 7.1 bar. This fluid is utilized in the power plant based on a supercritical organic Rankine cycle to generate a net electrical power of 5.5 MW. The main components of the power plant are as follows: steam turbines, heat exchangers, a desuperheater, an air-cooled condenser, a generator, and pumps. In the thermodynamic analysis of the power plant, effect of different working fluids on performances is investigated. Thermodynamic properties of each state of the plant are found applying energy balances for each component using the actual operating data taken from the power plant. The equations based on these balances developed by were programmed using Engineering Equations Solver (EES). Using this code, the power output of the turbines, the power demand of the pumps, the heat input to the heat exchanger, and the net power output and the electrical efficiency of the cycle are determined.