André Chun - Academia.edu (original) (raw)
Papers by André Chun
Engenharia térmica, Apr 12, 2021
The present work aims to carry out an off-design turbocharger modelling powered by exhaust gases ... more The present work aims to carry out an off-design turbocharger modelling powered by exhaust gases from a Wärtsilä 20V34SG engine. First of all, 1-D engine model was already developed in GT-Power software while considering a thermodynamic turbocharger modelling with constant isentropic efficiencies. Secondly, by using the results from 1-D engine model, the off-design turbocharger modelling is calibrated separately in EES software, taking into account compressible assumption, triangle velocities and geometric dimensions. The case study is derived from a R&D project (ANEEL PD-06483-0318/2018) that targets to cool and dehumidify the intake air at compressor's upstream through a cooling coil, thereby allowing engine's operation at reduced knocking conditions. The brake mean effective pressure (BMEP) is varied in the range of 20 to 23.45 bar, corresponding to brake power from 8.7 to 10.2 MW, respectively. With the off-design turbocharger modelling it is possible to analyze its operational behavior under higher BMEP, hence, allowing to predict some important parameters. The results showed that the turbocharger is operating within the manufacturer's limit for BMEP of 23.45 bar, presenting total-to-static isentropic efficiencies of 0.81 and 0.784 for compressor and turbine, respectively, rotational speed around 28135 RPM, pressure ratio at compressor of 4.567 and maintaining control on waste-gate valve.
International journal of energy and water resources, Nov 16, 2019
In this work, a multi-effect distillation with thermal vapor compression desalination unit is pro... more In this work, a multi-effect distillation with thermal vapor compression desalination unit is proposed to satisfy the freshwater demand of São Mateus, Espírito Santo, Brazil. The desalination unit is driven by saturated vapor produced by boiler or heat recovery steam generator. The goal and main contribution of this work are, respectively, to compare and evaluate the most feasible configuration among a steam power cycle, gas turbine and combined cycle power plant. To accomplish this objective, the first and second laws of thermodynamics are used, and economic analyses are carried out for each option. In consequence, an optimization using a genetic algorithm shows the optimal results. The usage of an exergy-based approach for cost allocation assists in the best judgment. For instance, the combined cycle power plant driving a desalination unit presents the highest net power generation of 51.7 MW and a total cost rate of 24,811 US$ h −1 , which means a Leveled Cost of Energy of around 0.132 US$ kWh −1. In addition, it has the lowest exergetic and monetary costs of net power (2.316 kJ kJ −1 and 0.132 US$ kWh −1) and freshwater (17.9 kJ kJ −1 and 2.684 US$ kWh −1). However, it also has the highest environmental cost for net power (22.451 kgCO 2 kWh −1) and the second highest one for freshwater (196.120 × 10 −3 kgCO 2 m −3). Keywords Combined cycle • Exergoeconomics • Gas turbine • Genetic algorithm • Multi-effect distillation • Steam cycle List of symbols c Monetary unit cost [US$ kWh −1 ] CRF Annual capital recovery factor DTML Logarithmic mean temperature difference [°C] E Exergy [kW] h Specific enthalpy [kJ kg −1 ] k Exergetic unit cost [kW kW −1 ] m Mass flow rate [kg s −1 ] N Hour of plant operation per year [h] OF Objective function
Proceedings of the 26th International Congress of Mechanical Engineering, 2021
Revista de Engenharia Térmica, 2021
Large internal combustion engines (ICEs) performance is limited by knocking phenomenon due to har... more Large internal combustion engines (ICEs) performance is limited by knocking phenomenon due to harsh ambient conditions such as hot temperature and excessive humidity. The performance of these engines can be enhanced by cooling and dehumidifying the inlet air on turbocharger upstream under safe operation conditions through a cooling coil heat exchanger, hence, increasing the power output as well as reducing the brake specific fuel consumption and pollutant specific emissions. Analysis have been performed in the GT-POWER software through a 1-D thermodynamic modelling of the Wärtsilä W20V34SG engine, making it possible to verify the influence of cooled and dehumidified ambient air, considering a temperature range from 9.5°C (282.7 K) to 15.5°C (288.7 K), while keeping 1 bar for pressure and relative humidity of 100%. Furthermore, the brake mean effective pressure (BMEP) has been set from 20 to 23.45 bar with a step of 1.15 bar. Such simulations are aimed to find the maximum air tempera...
Procceedings of the 18th Brazilian Congress of Thermal Sciences and Engineering, 2020
The present work aims to carry out an off-design turbocharger modelling powered by exhaust gases ... more The present work aims to carry out an off-design turbocharger modelling powered by exhaust gases from a Wärtsilä 20V34SG engine. First of all, 1-D engine model was already developed in GT-Power software while considering a thermodynamic turbocharger modelling with constant isentropic efficiencies. Secondly, by using the results from 1-D engine model, the off-design turbocharger modelling is calibrated separately in EES software, taking into account compressible assumption, triangle velocities and geometric dimensions. The case study is derived from a R&D project (ANEEL PD-06483-0318/2018) that targets to cool and dehumidify the intake air at compressor's upstream through a cooling coil, thereby allowing engine's operation at reduced knocking conditions. The brake mean effective pressure (BMEP) is varied in the range of 20 to 23.45 bar, corresponding to brake power from 8.7 to 10.2 MW, respectively. With the off-design turbocharger modelling it is possible to analyze its operational behavior under higher BMEP, hence, allowing to predict some important parameters. The results showed that the turbocharger is operating within the manufacturer's limit for BMEP of 23.45 bar, presenting total-to-static isentropic efficiencies of 0.81 and 0.784 for compressor and turbine, respectively, rotational speed around 28135 RPM, pressure ratio at compressor of 4.567 and maintaining control on waste-gate valve.
Procceedings of the 18th Brazilian Congress of Thermal Sciences and Engineering, 2020
Revista de Engenharia Térmica, 2020
This work presents an alternative design for an experimental waste heat recovery thermal system t... more This work presents an alternative design for an experimental waste heat recovery thermal system to be coupled to a large turbocharged internal combustion engine for combustion air conditioning. The goal is to carry out a design of a new thermal system under restricted economic requirements for one of the generators set of Luiz Oscar Rodrigues de Melo Thermoelectric Power Plant. Thereby, a comparison with the original proposal from previous works is also developed in order to demonstrate the differences in terms of thermo-economic design parameters. The waste recovery thermal system produces sufficient chilled water through a single-effect absorption chiller, powered by hot water which is produced by recovering the exhaust gases residual heat to supply cooling applications on the combustion air. The results showed a significant reduction for the chiller capacity demand, from 550 to 185 RT, that would be enough to provide chilled water for 98.72% of the analyzed operation historical p...
17th Brazilian Congress of Thermal Sciences and Engineering, 2018
17th Brazilian Congress of Thermal Sciences and Engineering, 2018
Procceedings of the 24th ABCM International Congress of Mechanical Engineering, 2017
Proceedings of the 26th International Congress of Mechanical Engineering, 2021
Journal of The Brazilian Society of Mechanical Sciences and Engineering, 2021
Energy Conversion and Management
Energy Conversion and Management
Engenharia térmica, Apr 12, 2021
The present work aims to carry out an off-design turbocharger modelling powered by exhaust gases ... more The present work aims to carry out an off-design turbocharger modelling powered by exhaust gases from a Wärtsilä 20V34SG engine. First of all, 1-D engine model was already developed in GT-Power software while considering a thermodynamic turbocharger modelling with constant isentropic efficiencies. Secondly, by using the results from 1-D engine model, the off-design turbocharger modelling is calibrated separately in EES software, taking into account compressible assumption, triangle velocities and geometric dimensions. The case study is derived from a R&D project (ANEEL PD-06483-0318/2018) that targets to cool and dehumidify the intake air at compressor's upstream through a cooling coil, thereby allowing engine's operation at reduced knocking conditions. The brake mean effective pressure (BMEP) is varied in the range of 20 to 23.45 bar, corresponding to brake power from 8.7 to 10.2 MW, respectively. With the off-design turbocharger modelling it is possible to analyze its operational behavior under higher BMEP, hence, allowing to predict some important parameters. The results showed that the turbocharger is operating within the manufacturer's limit for BMEP of 23.45 bar, presenting total-to-static isentropic efficiencies of 0.81 and 0.784 for compressor and turbine, respectively, rotational speed around 28135 RPM, pressure ratio at compressor of 4.567 and maintaining control on waste-gate valve.
International journal of energy and water resources, Nov 16, 2019
In this work, a multi-effect distillation with thermal vapor compression desalination unit is pro... more In this work, a multi-effect distillation with thermal vapor compression desalination unit is proposed to satisfy the freshwater demand of São Mateus, Espírito Santo, Brazil. The desalination unit is driven by saturated vapor produced by boiler or heat recovery steam generator. The goal and main contribution of this work are, respectively, to compare and evaluate the most feasible configuration among a steam power cycle, gas turbine and combined cycle power plant. To accomplish this objective, the first and second laws of thermodynamics are used, and economic analyses are carried out for each option. In consequence, an optimization using a genetic algorithm shows the optimal results. The usage of an exergy-based approach for cost allocation assists in the best judgment. For instance, the combined cycle power plant driving a desalination unit presents the highest net power generation of 51.7 MW and a total cost rate of 24,811 US$ h −1 , which means a Leveled Cost of Energy of around 0.132 US$ kWh −1. In addition, it has the lowest exergetic and monetary costs of net power (2.316 kJ kJ −1 and 0.132 US$ kWh −1) and freshwater (17.9 kJ kJ −1 and 2.684 US$ kWh −1). However, it also has the highest environmental cost for net power (22.451 kgCO 2 kWh −1) and the second highest one for freshwater (196.120 × 10 −3 kgCO 2 m −3). Keywords Combined cycle • Exergoeconomics • Gas turbine • Genetic algorithm • Multi-effect distillation • Steam cycle List of symbols c Monetary unit cost [US$ kWh −1 ] CRF Annual capital recovery factor DTML Logarithmic mean temperature difference [°C] E Exergy [kW] h Specific enthalpy [kJ kg −1 ] k Exergetic unit cost [kW kW −1 ] m Mass flow rate [kg s −1 ] N Hour of plant operation per year [h] OF Objective function
Proceedings of the 26th International Congress of Mechanical Engineering, 2021
Revista de Engenharia Térmica, 2021
Large internal combustion engines (ICEs) performance is limited by knocking phenomenon due to har... more Large internal combustion engines (ICEs) performance is limited by knocking phenomenon due to harsh ambient conditions such as hot temperature and excessive humidity. The performance of these engines can be enhanced by cooling and dehumidifying the inlet air on turbocharger upstream under safe operation conditions through a cooling coil heat exchanger, hence, increasing the power output as well as reducing the brake specific fuel consumption and pollutant specific emissions. Analysis have been performed in the GT-POWER software through a 1-D thermodynamic modelling of the Wärtsilä W20V34SG engine, making it possible to verify the influence of cooled and dehumidified ambient air, considering a temperature range from 9.5°C (282.7 K) to 15.5°C (288.7 K), while keeping 1 bar for pressure and relative humidity of 100%. Furthermore, the brake mean effective pressure (BMEP) has been set from 20 to 23.45 bar with a step of 1.15 bar. Such simulations are aimed to find the maximum air tempera...
Procceedings of the 18th Brazilian Congress of Thermal Sciences and Engineering, 2020
The present work aims to carry out an off-design turbocharger modelling powered by exhaust gases ... more The present work aims to carry out an off-design turbocharger modelling powered by exhaust gases from a Wärtsilä 20V34SG engine. First of all, 1-D engine model was already developed in GT-Power software while considering a thermodynamic turbocharger modelling with constant isentropic efficiencies. Secondly, by using the results from 1-D engine model, the off-design turbocharger modelling is calibrated separately in EES software, taking into account compressible assumption, triangle velocities and geometric dimensions. The case study is derived from a R&D project (ANEEL PD-06483-0318/2018) that targets to cool and dehumidify the intake air at compressor's upstream through a cooling coil, thereby allowing engine's operation at reduced knocking conditions. The brake mean effective pressure (BMEP) is varied in the range of 20 to 23.45 bar, corresponding to brake power from 8.7 to 10.2 MW, respectively. With the off-design turbocharger modelling it is possible to analyze its operational behavior under higher BMEP, hence, allowing to predict some important parameters. The results showed that the turbocharger is operating within the manufacturer's limit for BMEP of 23.45 bar, presenting total-to-static isentropic efficiencies of 0.81 and 0.784 for compressor and turbine, respectively, rotational speed around 28135 RPM, pressure ratio at compressor of 4.567 and maintaining control on waste-gate valve.
Procceedings of the 18th Brazilian Congress of Thermal Sciences and Engineering, 2020
Revista de Engenharia Térmica, 2020
This work presents an alternative design for an experimental waste heat recovery thermal system t... more This work presents an alternative design for an experimental waste heat recovery thermal system to be coupled to a large turbocharged internal combustion engine for combustion air conditioning. The goal is to carry out a design of a new thermal system under restricted economic requirements for one of the generators set of Luiz Oscar Rodrigues de Melo Thermoelectric Power Plant. Thereby, a comparison with the original proposal from previous works is also developed in order to demonstrate the differences in terms of thermo-economic design parameters. The waste recovery thermal system produces sufficient chilled water through a single-effect absorption chiller, powered by hot water which is produced by recovering the exhaust gases residual heat to supply cooling applications on the combustion air. The results showed a significant reduction for the chiller capacity demand, from 550 to 185 RT, that would be enough to provide chilled water for 98.72% of the analyzed operation historical p...
17th Brazilian Congress of Thermal Sciences and Engineering, 2018
17th Brazilian Congress of Thermal Sciences and Engineering, 2018
Procceedings of the 24th ABCM International Congress of Mechanical Engineering, 2017
Proceedings of the 26th International Congress of Mechanical Engineering, 2021
Journal of The Brazilian Society of Mechanical Sciences and Engineering, 2021
Energy Conversion and Management
Energy Conversion and Management