Georgios Spyropoulos | University of West Attica / Πανεπιστήμιο Δυτικής Αττικής (original) (raw)
Papers by Georgios Spyropoulos
Procedia structural integrity, 2018
During their operation, modern aircraft engine components are subjected to increasingly demanding... more During their operation, modern aircraft engine components are subjected to increasingly demanding operating conditions, especially the high pressure turbine (HPT) blades. Such conditions cause these parts to undergo different types of time-dependent degradation, one of which is creep. A model using the finite element method (FEM) was developed, in order to be able to predict the creep behaviour of HPT blades. Flight data records (FDR) for a specific aircraft, provided by a commercial aviation company, were used to obtain thermal and mechanical data for three different flight cycles. In order to create the 3D model needed for the FEM analysis, a HPT blade scrap was scanned, and its chemical composition and material properties were obtained. The data that was gathered was fed into the FEM model and different simulations were run, first with a simplified 3D rectangular block shape, in order to better establish the model, and then with the real 3D mesh obtained from the blade scrap. The overall expected behaviour in terms of displacement was observed, in particular at the trailing edge of the blade. Therefore such a model can be useful in the goal of predicting turbine blade life, given a set of FDR data.
Atmosphere, Feb 16, 2023
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
The Soft Energy Applications & Environmental Protection Laboratory of UNIWA has recently installe... more The Soft Energy Applications & Environmental Protection Laboratory of UNIWA has recently installed a small PV power station in order to offer zero-cost clean energy to the Tilos island community. The scope of this new PV station is twofold, i.e., first to cover the electricity consumption of the municipality building and secondly to meet the lighting (electricity) demand of the coastal street at the island harbor. On the other hand, the PV station is also supporting an electrical vehicle (EV) charging station, installed also in the same building in order to charge two EVs of the local municipality. According to the data gathered, it is obvious that the installed PV station contributes considerably on covering the electrical needs of the local municipal loads and EVs, while the developed solution may equally well apply in several other similar cases all around the Mediterranean Sea.
16th International Conference on Meteorology, Climatology and Atmospheric Physics—COMECAP 2023
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
16th International Conference on Meteorology, Climatology and Atmospheric Physics—COMECAP 2023
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
16th International Conference on Meteorology, Climatology and Atmospheric Physics—COMECAP 2023
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
This study provides a thorough review and analysis of the evolution of the Greek vehicle fleet ov... more This study provides a thorough review and analysis of the evolution of the Greek vehicle fleet over the last ~30 years, which is next used for the generation of high granularity fleet projections and for the estimation of relevant environmental benefits by 2030. The integrated methodology developed takes also into account vehicle clustering and the Brown’s Double Simple Exponential Smoothing technique that together with the adoption of COPERT based emission factors allow for the estimation of the anticipated emissions in 2030. Expected 2030 emissions levels suggest a reduction across all pollutants in comparison to 2018, ranging from 3.7% for PM10 to 54.5% for NMVOC (and 46% for CO, 14% for SO2, 28% for NOX and 21% for CO2). We find that Greece is on track with national goals concerning the reduction of air pollution from the transportation sector, stressing the positive contribution of EVs and new, "greener" vehicles, and setting new challenges for the further improvement...
Mediterranean Green Buildings & Renewable Energy, 2016
Improving energy efficiency in the transportation sector could significantly contribute to limiti... more Improving energy efficiency in the transportation sector could significantly contribute to limiting environmental degradation and decelerate the depletion of existing fossil-fuel reserves. Effective methods for increasing energy efficiency include the adoption of eco-driving – especially in urban areas – the utilization of more efficient vehicles, and the shift to green public transportation. In any case, to develop a sustainable and efficient transportation strategy in selected cases (e.g., smart cities), the use of so-called clean new technology vehicles should be adopted. The Laboratory of Soft Energy Applications and Environmental Protection (SEALAB) of the Piraeus University of Applied Sciences (formerly TEI of Piraeus) has recently undertaken, within the framework of its innovative activities, the development, construction, and operation of the country’s first stand-alone solar electric vehicle charging station (EVCS), CARPORT, monitoring all energy data and thereby supporting and strengthening the country’s efforts in infrastructure development in the field of electromobility. More specifically, this innovative effort, described in this chapter, aims to accelerate the implementation of a European national electrification action plan through the construction of EVCSs based on photovoltaic generators. The proposed solar EVCS is considered to be one of the most environmentally friendly solutions, capable of supporting the decarbonization of the European transport sector.
Most people living in Europe's cities are still exposed to levels of air pollution deemed har... more Most people living in Europe's cities are still exposed to levels of air pollution deemed harmful by the World Health Organization. In the modern world, air pollution is the foremost concern because of its impact in human health and economy. This strong connection appears gaining a lot of concern, driven by new installed low-cost electrochemical sensors monitoring systems. Highly accuracy, real-time monitoring, daily and yearly statistics, data access from experts or simple users, low-cost equipment and forecasting needs, enforce the market to develop new air quality monitoring systems using advanced technologies and protocols. In this study, a comparison via low-cost electrochemical sensors and of static, fixed site measurement monitoring station, is taking place in Athens, Greece, along with the data quality and Air Quality Index (AQI) including data accuracy and quality of data concerning adverse health effects due to air pollution. The findings presented in this work, relate...
Energy Reports
Abstract Electric Vehicles (EVs), accompanied with the use of Renewable Energy Sources (RES), are... more Abstract Electric Vehicles (EVs), accompanied with the use of Renewable Energy Sources (RES), are the solution for the decarbonization of the transport sector and are undoubtedly on the rise. Although EVs have been in the limelight over the last decade, little effort has been made towards the proper use of the vehicle’s battery. Therefore, a better understanding of Lithium-ion (Li-ion) batteries, since they represent the heart of the majority of electric cars, during the discharging and charging procedure is crucial. The present study, that was experimentally conducted under real-world driving conditions, quantitatively analyzes the energy losses that take place during the charging of a Battery Electric Vehicle (BEV), focusing especially in the previously unexplored 80%–100% State of Charge (SoC) area. The results show that losses, during charging within the abovementioned area, are almost double compared to the 20%–80% SoC area and vehicle’s average specific real energy consumption is almost 2 kWh/100 km more, compared to what the driver sees on the EV’s dashboard. Furthermore, it is not for the driver’s benefit to exceed 80% of SoC during charging, considering the required charging time, the distance that each SoC area provides and the life expectancy of the battery itself. Based on these results and after a thorough literature review, the authors suggest the optimum SoC range within which drivers should operate the EV’s battery.
ABSTRACT Electricity is characterized as the most end-user friendly form of energy. However, the ... more ABSTRACT Electricity is characterized as the most end-user friendly form of energy. However, the electricity generation - based so far on fossil fuels - is found guilty of significant air pollu-tion, including the annual emission of more than 350 ktnons of sulphur dioxide, representing 80% of the national re-leases. In this context, the existing large combustion power plants are classified according to their SO2 emission factor. In the present study we calculate the SO2 emissions, re-sulting by using, in priority, the most environmental friendly power stations, to face the electricity load requirements of the Greek mainland. In the methodology adopted one dis-regards, during the selection procedure among the available Greek power plants, any operational, grid-stability, system-efficiency and cost-effectiveness criteria. Using this purely theoretical methodology, one has the ability to estimate the minimum expected SO2 annual emission from the existing power plants, used to fulfil the corresponding national electricity demand. The discrepancy encountered is due to the established classification of the existing power plants, which practically neglects the im-pact of the sulphur dioxide emissions.
Procedia structural integrity, 2018
During their operation, modern aircraft engine components are subjected to increasingly demanding... more During their operation, modern aircraft engine components are subjected to increasingly demanding operating conditions, especially the high pressure turbine (HPT) blades. Such conditions cause these parts to undergo different types of time-dependent degradation, one of which is creep. A model using the finite element method (FEM) was developed, in order to be able to predict the creep behaviour of HPT blades. Flight data records (FDR) for a specific aircraft, provided by a commercial aviation company, were used to obtain thermal and mechanical data for three different flight cycles. In order to create the 3D model needed for the FEM analysis, a HPT blade scrap was scanned, and its chemical composition and material properties were obtained. The data that was gathered was fed into the FEM model and different simulations were run, first with a simplified 3D rectangular block shape, in order to better establish the model, and then with the real 3D mesh obtained from the blade scrap. The overall expected behaviour in terms of displacement was observed, in particular at the trailing edge of the blade. Therefore such a model can be useful in the goal of predicting turbine blade life, given a set of FDR data.
Atmosphere, Feb 16, 2023
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
The Soft Energy Applications & Environmental Protection Laboratory of UNIWA has recently installe... more The Soft Energy Applications & Environmental Protection Laboratory of UNIWA has recently installed a small PV power station in order to offer zero-cost clean energy to the Tilos island community. The scope of this new PV station is twofold, i.e., first to cover the electricity consumption of the municipality building and secondly to meet the lighting (electricity) demand of the coastal street at the island harbor. On the other hand, the PV station is also supporting an electrical vehicle (EV) charging station, installed also in the same building in order to charge two EVs of the local municipality. According to the data gathered, it is obvious that the installed PV station contributes considerably on covering the electrical needs of the local municipal loads and EVs, while the developed solution may equally well apply in several other similar cases all around the Mediterranean Sea.
16th International Conference on Meteorology, Climatology and Atmospheric Physics—COMECAP 2023
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
16th International Conference on Meteorology, Climatology and Atmospheric Physics—COMECAP 2023
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
16th International Conference on Meteorology, Climatology and Atmospheric Physics—COMECAP 2023
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
This study provides a thorough review and analysis of the evolution of the Greek vehicle fleet ov... more This study provides a thorough review and analysis of the evolution of the Greek vehicle fleet over the last ~30 years, which is next used for the generation of high granularity fleet projections and for the estimation of relevant environmental benefits by 2030. The integrated methodology developed takes also into account vehicle clustering and the Brown’s Double Simple Exponential Smoothing technique that together with the adoption of COPERT based emission factors allow for the estimation of the anticipated emissions in 2030. Expected 2030 emissions levels suggest a reduction across all pollutants in comparison to 2018, ranging from 3.7% for PM10 to 54.5% for NMVOC (and 46% for CO, 14% for SO2, 28% for NOX and 21% for CO2). We find that Greece is on track with national goals concerning the reduction of air pollution from the transportation sector, stressing the positive contribution of EVs and new, "greener" vehicles, and setting new challenges for the further improvement...
Mediterranean Green Buildings & Renewable Energy, 2016
Improving energy efficiency in the transportation sector could significantly contribute to limiti... more Improving energy efficiency in the transportation sector could significantly contribute to limiting environmental degradation and decelerate the depletion of existing fossil-fuel reserves. Effective methods for increasing energy efficiency include the adoption of eco-driving – especially in urban areas – the utilization of more efficient vehicles, and the shift to green public transportation. In any case, to develop a sustainable and efficient transportation strategy in selected cases (e.g., smart cities), the use of so-called clean new technology vehicles should be adopted. The Laboratory of Soft Energy Applications and Environmental Protection (SEALAB) of the Piraeus University of Applied Sciences (formerly TEI of Piraeus) has recently undertaken, within the framework of its innovative activities, the development, construction, and operation of the country’s first stand-alone solar electric vehicle charging station (EVCS), CARPORT, monitoring all energy data and thereby supporting and strengthening the country’s efforts in infrastructure development in the field of electromobility. More specifically, this innovative effort, described in this chapter, aims to accelerate the implementation of a European national electrification action plan through the construction of EVCSs based on photovoltaic generators. The proposed solar EVCS is considered to be one of the most environmentally friendly solutions, capable of supporting the decarbonization of the European transport sector.
Most people living in Europe's cities are still exposed to levels of air pollution deemed har... more Most people living in Europe's cities are still exposed to levels of air pollution deemed harmful by the World Health Organization. In the modern world, air pollution is the foremost concern because of its impact in human health and economy. This strong connection appears gaining a lot of concern, driven by new installed low-cost electrochemical sensors monitoring systems. Highly accuracy, real-time monitoring, daily and yearly statistics, data access from experts or simple users, low-cost equipment and forecasting needs, enforce the market to develop new air quality monitoring systems using advanced technologies and protocols. In this study, a comparison via low-cost electrochemical sensors and of static, fixed site measurement monitoring station, is taking place in Athens, Greece, along with the data quality and Air Quality Index (AQI) including data accuracy and quality of data concerning adverse health effects due to air pollution. The findings presented in this work, relate...
Energy Reports
Abstract Electric Vehicles (EVs), accompanied with the use of Renewable Energy Sources (RES), are... more Abstract Electric Vehicles (EVs), accompanied with the use of Renewable Energy Sources (RES), are the solution for the decarbonization of the transport sector and are undoubtedly on the rise. Although EVs have been in the limelight over the last decade, little effort has been made towards the proper use of the vehicle’s battery. Therefore, a better understanding of Lithium-ion (Li-ion) batteries, since they represent the heart of the majority of electric cars, during the discharging and charging procedure is crucial. The present study, that was experimentally conducted under real-world driving conditions, quantitatively analyzes the energy losses that take place during the charging of a Battery Electric Vehicle (BEV), focusing especially in the previously unexplored 80%–100% State of Charge (SoC) area. The results show that losses, during charging within the abovementioned area, are almost double compared to the 20%–80% SoC area and vehicle’s average specific real energy consumption is almost 2 kWh/100 km more, compared to what the driver sees on the EV’s dashboard. Furthermore, it is not for the driver’s benefit to exceed 80% of SoC during charging, considering the required charging time, the distance that each SoC area provides and the life expectancy of the battery itself. Based on these results and after a thorough literature review, the authors suggest the optimum SoC range within which drivers should operate the EV’s battery.
ABSTRACT Electricity is characterized as the most end-user friendly form of energy. However, the ... more ABSTRACT Electricity is characterized as the most end-user friendly form of energy. However, the electricity generation - based so far on fossil fuels - is found guilty of significant air pollu-tion, including the annual emission of more than 350 ktnons of sulphur dioxide, representing 80% of the national re-leases. In this context, the existing large combustion power plants are classified according to their SO2 emission factor. In the present study we calculate the SO2 emissions, re-sulting by using, in priority, the most environmental friendly power stations, to face the electricity load requirements of the Greek mainland. In the methodology adopted one dis-regards, during the selection procedure among the available Greek power plants, any operational, grid-stability, system-efficiency and cost-effectiveness criteria. Using this purely theoretical methodology, one has the ability to estimate the minimum expected SO2 annual emission from the existing power plants, used to fulfil the corresponding national electricity demand. The discrepancy encountered is due to the established classification of the existing power plants, which practically neglects the im-pact of the sulphur dioxide emissions.