Influence of Variable Speed Limit Control on Fuel and Electric Energy Consumption, and Exhaust Gas Emissions in Mixed Traffic Flows

Modern urban mobility needs new solutions to resolve high-complexity demands on urban traffic-control systems, including reducing congestion, fuel and energy consumption, and exhaust gas emissions. One example is urban motorways as key segments of the urban traffic network that do not achieve a satisfactory level of service to serve the increasing traffic demand. Another complex need arises by introducing the connected and autonomous vehicles (CAVs) and accompanying additional challenges that modern control systems must cope with. This study addresses the problem of decreasing the negative environmental aspects of traffic, which includes reducing congestion, fuel and energy consumption, and exhaust gas emissions. We applied a variable speed limit (VSL) based on Q-Learning that utilizes electric CAVs as speed-limit actuators in the control loop. The Q-Learning algorithm was combined with the two-step temporal difference target to increase the algorithm’s effectiveness for learning the VSL control policy for mixed traffic flows. We analyzed two different optimization criteria: total time spent on all vehicles in the traffic network and total energy consumption. Various mixed traffic flow scenarios were addressed with varying CAV penetration rates, and the obtained results were compared with a baseline no-control scenario and a rule-based VSL. The data about vehicle-emission class and the share of gasoline and diesel human-driven vehicles were taken from the actual data from the Croatian Bureau of Statistics. The obtained results show that Q-Learning-based VSL can learn the control policy and improve the macroscopic traffic parameters and total energy consumption and can reduce exhaust gas emissions for different electric CAV penetration rates. The results are most apparent in cases with low CAV penetration rates. Additionally, the results indicate that for the analyzed traffic demand, the increase in the CAV penetration rate alleviates the need to impose VSL control on an urban motorway.

Comparative Analysis of Real Fires for Electric Vehicles and Gasoline Vehicles

Recently, the demand for electric vehicles has increased rapidly as eco-friendly vehicles to regulate exhaust gas emissions. However, fire accidents related to electric vehicles are also occurring frequently. In the present work, to design a fire suppression plan for electric vehicles, a comparison of electric and gasoline vehicles has been demonstrated through real fire experiments. Temperature measurements have been performed using a heat flux sensor to understand the characteristics of each fire. At the peak of fire, the maximum temperature was measured to be about 1,390 ℃ or higher. Further, it was confirmed that gasoline vehicles exhibit higher temperature gains than electric vehicles.

THE CHANCES FOR REDUCTION OF VIBRATIONS IN MECHANICAL SYSTEM WITH LOW-EMISSION SHIPS COMBUSTION ENGINES

Development of diesel engines is focused on reduction of exhaust gas emissions, increase of efficiency of the fuel mixture combustion and decrease of fuel consumption. Such engines are referred to as low-emission engines. Low- engines trends bring higher engine power outputs, torques and also increase of vibrations and noisiness level. In order to reduce these vibrations of diesel engines, it is necessary to apply different dynamical elements, which are able to increase an adverse impact of exciting amplitudes. One of the results is application of a pneumatic dual-mass flywheel. The pneumatic dual-mass flywheel is a dynamical element that consists of two masses (the primary and the secondary mass), which are jointed together by means of a flexible interconnection. This kind of the flywheel solution enables to change resonance areas of the mechanical system which consequently leads to reduction of vibrations.

DECISION SUPPORT SYSTEM FOR POWER GENERATION MANAGEMENT FOR AN 110000+ GRT CRUISE SHIP

The aim of this work is to provide a methodology for the power generation optimization on large cruise ships in order to improve their operating efficiency, fuel saving and, consequently, to reduce exhaust gas emissions. The electrical load analysis is compared to the machinery reports of actual data in order to investigate if the estimated required power is appropriately close to the real power demand. Relevance is given to the average load of the diesel-generators, which expresses an indication of how the generators work. The model of the ship electric distribution system represents one of the main objectives of this work along with the power system simulations. These were developed through the definition of load profiles, both by the onboard recordings and by machinery reports data. Therefore, the same cruise profile is analyzed under different scenarios, the real and the optimized one, in order to highlight the critical state of the system and any possible margin for improvement.

Numerical Study on the Performance and NOx Emission Characteristics of an 800cc MPI Turbocharged SI Engine

The main purpose of this study is to optimize engine performance and emission characteristics of off-road engines with retarded spark timing compared to MBT by repurposing the existing passenger engine. This study uses a one-dimensional (1D)-simulation to develop a non-road gasoline MPI turbo engine. The SI turbulent flame model of the GT-suite, an operational performance predictable program, presents turbocharger matching and optimal operation design points. To optimize the engine performance, the SI turbulent model uses three operation parameters: spark timing, intake valve overlap, and boost pressure. Spark timing determines the initial state of combustion and thermal efficiency, and is the main variable of the engine. The maximum brake torque (MBT) point can be identified for spark timing, and abnormal combustion phenomena, such as knocking, can be identified. Spark timing is related to engine performance, and emissions of exhaust pollutants are predictable. If the spark timing is set to variables, the engine performance and emissions can be confirmed and predicted. The intake valve overlap can predict the performance and exhaust gas by controlling the airflow and combustion chamber flow, and can control the performance of the engine by controlling the flow in the cylinder. In addition, a criterion can be set to consider the optimum operating point of the non-road vehicle while investigating the performance and exhaust gas emissions accompanying changes in boost pressure With these parameters, the design of experiment (DoE) of the 1D-simulation is performed, and the driving performance and knocking phenomenon for each RPM are predicted during the wide open throttle (WOT) of the gasoline MPI Turbo SI engine. The multi-objective Pareto technique is also used to optimize engine performance and exhaust gas emissions, and to present optimized design points for the target engine, the downsized gasoline MPI Turbo SI engine. The results of the Pareto optimal solution showed a maximum torque increase of 12.78% and a NOx decrease of 54.31%.

Optimization of the Belinyu solar power plant to reduce emissions of waste gas in diesel power plant

The operation of a diesel power plant not only improves reliability but also has an impact on the environment in the Belinyu sub-district. The purpose of this PLTD development is to meet the increasing electricity demand. Environmental aspects in the construction of this PLTD include exhaust gas emission factors which are pivotal to notice. Meanwhile, this low emission power plant located next to the diesel power plant has not yet had an optimal operating pattern because there is no energy storage system. By optimizing the design of the solar power plant and optimization the operating pattern of the diesel power plant, it has the potential to reduce the operating hours of the diesel power plant engine as well as the potential to reduce exhaust gas emissions in the amount of 0.0060264 mn tons CO2/year.

Evaluating the effect of DEE blending ratio in biogas-biodiesel fuelled dual-fuel engine

Fossil fuels are depleting faster than being consumed. Fuels with higher efficiency, less consumability, and ecocity are very much desired for the present scenario. In this investigation, a conventional single-cylinder CI engine is utilized in dual-fuel mode, in which biogas is the primary fuel while biodiesel (palm oil) with different DEE blending ratios is used (5%, 10%, and 15%) as a secondary fuel. For each DEE blend, biogas flow rate and loads are varied and their effect on brake thermal efficiency, pilot fuel energy ratio, CO, NOx, and HC emissions are estimated. Exhaust gas emissions were calculated using an AVL 5-gas emission analyser. The calorific value and density of each sample are calculated. It is witnessed from the experiments that 5% DEE used with lower biogas flow rate resulted in high brake thermal efficiency of 31.83%. Also, an increase in DEE is found to increase NOx emission while an increase in biogas flow rate resulted in a reduction in NOx emission. The addition of biogas is experimentally observed to have the potential in reducing pilot fuel consumption.

Potential Benefits Of Electricaly Driven Ferry, Case Study

There have been several news articles in the newspapers lately about the introduction of electrically powered ferry boats in Croatia, especially on several shorter routes. This introduction will require serious investigation into potential benefits and also into potential drawbacks to determine if a solution is viable or not. One of those shorter ferry routes in Croatia is a route from peninsula Pelješac to the island of Korčula. The route at the moment is operated by one ferry, driven by four independent propellers, each driven by one diesel engine. This paper is addressing one small aspect of problems, assessing potential benefits of the conversion of a ferry (or replacement with electrically driven ferry) on the mentioned route to electrical power and the impact on the local area due to the reduction of all exhaust gas emissions.

The Measurement Of Exhaust Gas Emissions By Testo 350 Maritime – Exhaust Gas Analyzer

This paper presents the measurement process of the emissions from marine diesel engines. The emission measurement was carried out by the certified TESTO 350 Maritime exhaust gas analyzer on the Juraj Dalmatinac ferry Caterpillar C32 engines. The gas analyzer records the concentrations of nitrogen oxides (NOx), carbon monoxide (CO), carbon dioxide (CO2), oxygen (O2) and sulfur dioxide (SO2). TESTO 350 emission sampling probe was set at the end of the exhaust pipe. A combustion emission measurement was performed during a Split – Supetar (Brač) trip and backwards with the total duration of 110 min. The emissions are estimated for two trip phases: “maneuvering” and “at sea”.

A Review of Low-CO2 Emission Fuels for a Dual-Fuel RCCI Engine

This article discusses the problems of exhaust gas emissions in the context of the possibility of their reduction through the use of fuels with hydrogen as an additive or hydrotreatment. These fuels, thanks to their properties, may be a suitable response to more and more demanding restrictions on exhaust emissions. The use of such fuels in reactivity controlled dual fuel engines (RCCI) is currently the most effective way of using them in internal combustion (IC) engines. Low-temperature combustion in this type of engine allows the use of all modern fuels intended for combustion engines with high thermal efficiency. Thermal efficiency higher than in classic engines allows for additional reduction of CO2 emissions. In this work, the research on this subject was compiled, and conclusions were drawn as to further possibilities of popularizing the use of these fuels in a wide spectrum of applications and the prospect of using them on a mass scale.