scholarly journals Emission of selected exhaust compounds in jet engines of a jet aircraft in cruise phase

2018 ◽  
Vol 173 (2) ◽  
pp. 67-72
Author(s):  
Małgorzata PAWLAK ◽  
Andrzej MAJKA ◽  
Michał KUŹNIAR ◽  
Jowita PAWLUCZY
Keyword(s):  
Fuel Consumption ◽  
Environmentally Friendly ◽  
Specific Fuel Consumption ◽  
Air Transport ◽  
Development Phase ◽  
Jet Engines ◽  
Fuel Consumption And Emissions

Nowadays, air transport is in an intense development phase. In order to optimize air communication and make it even more economical and environmentally friendly, attempts are made to undertake such activities as, e.g., SESAR project, which aims to develop and implement a modern ATM system. One of the parts of this project is the research on minimizing fuel consumption and emissions of pollu-tants in the engine exhausts. In the paper there is therefore presented the methodology for determining emission of those pollutants for the longest stage of the flight – the cruise phase. First, the value of the thrust required for the flight of an exemplary aircraft was deter-mined, and then the values of the engines trust and specific fuel consumption were computed. Additionally, it was necessary to determine the Emission Indexes (EI) of CO, NOx, HC and CO2 for the cruise phase, based on known such indexes for the LTO. Total emissions of these pollutants for the mission adopted to conduct research – a 1000 km long cruise – were determined. These emissions were computed for the exemplary aircraft per one kilometre, as well as per one hour of flight for various cruising altitudes and flight speeds.

scholarly journals Analysis of wind impact on emission of selected exhaust compounds in jet engines of a business jet aircraft in cruise phase

2018 ◽  
Vol 173 (2) ◽  
pp. 55-60
Author(s):  
Małgorzata PAWLAK ◽  
Andrzej MAJKA ◽  
Michał KUŹNIAR ◽  
Jowita PAWLUCZY
Keyword(s):  
Wind Speed ◽  
Fuel Consumption ◽  
Wind Direction ◽  
Adverse Impact ◽  
Air Transport ◽  
Jet Engines ◽  
Business Jet ◽  
Condi Tions ◽  
Harmful Substances ◽  
The Impact

Among the most important problems currently faced by air transport, we can distinguish the adverse impact of aircrafts on the natu-ral environment, as well as the rising costs of transport. One of the possibilities to improve this situation is better adjustment of aircraft characteristics to the performed transport tasks, taking into account all the requirements and limitations that exist in air traffic and the adverse impact of air transport on the natural environment. It is reflected in the research tasks conducted under the SESAR program. The aspiration to minimize the adverse impact of aircrafts on the environment is executed, among others, through determining such trajectories that are characterized by minimal fuel consumption or minimal emission of harmful substances in the engines exhausts. These goals are corresponding with the research conducted and described in the paper. The main aim of the work was to analyse the impact of wind speed and direction on the emission of harmful substances of a jet aircraft performing a flight on a given route. For research purposes, the route between two Polish cities Gdansk and Rzeszow was considered. The distance between the two airports was divided into sections for which wind direction and strength were determined (read from the windy.com website). Next, the aircraft per-formance was determined and the fuel consumption and the amount of harmful compounds (CO2, NOx, CO and HC), emitted in the en-gines exhausts were determined for the route from Gdansk to Rzeszow (under favourable wind conditions) and on the return route – from Rzeszow to Gdansk (under unfavourable wind conditions). For comparative purposes, emission of these substances for windless condi-tions was also determined. The results are presented in tables and depicted in the graph, as well as discussed in the conclusions of the paper.

scholarly journals The Potential of Sequential Combustion for High Bypass Jet Engines

1998 ◽  
Author(s):  
Konrad Vogeler
Keyword(s):  
Fuel Consumption ◽  
Specific Fuel Consumption ◽  
Maximum Pressure ◽  
Jet Engines ◽  
Gas Temperature ◽  
Core Mass ◽  
New Family ◽  
Fuel Flow ◽  
Lp Turbine ◽  
Bypass Ratio

ABB has designed a new family of industrial gasturbines for power generation using a Sequential Combustion Cycle (SCC) on a large single shaft engine. This concept allows considerable increase in power density and efficiency by only increasing pressure without raising the maximum hot gas temperature of the cycle. Instead a second combustion after an HP-turbine is used to reheat the gas before the final expansion in an LP-turbine. This concept is applied to the analysis of a high bypass ratio jet engine. In an engine with a single combustor, thrust is a function of bypass ratio and the combination of maximum pressure and temperature in the cycle. The proposed SCC allows increased thrust without pushing technology on materials and cooling. A modern twin spool engine is taken as reference. When total inlet massflow is kept constant, increasing bypass ratio decreases core mass flow. This limits the fuel flow for the HP-spool and hence total energy input to the engine. Introduction of the SCC gives another parameter of freedom to the cycle design. However the twin spool concept is now a disadvantage. The low fuel flow for the HP-spool due to high bypass ratio means there is not enough energy available to build up the necessary pressure for an economical expansion in the LP-turbine after the second combustion. Specific fuel consumption will be unacceptable. It is proposed to apply the SCC concept in a single spool engine with a geared fan. Both turbines can now support the compression. The fan is operated as a constant speed propeller with variable blade pitch. This engine concept allows for a given inlet massflow a substantially higher bypass ratio and hence decreases specific fuel consumption while specific thrust can be kept on a level which will be considerably higher than it would be in todays engines with comparable bypass ratio.

scholarly journals MODEL OF EMISSION OF EXHAUST COMPOUNDS OF JET AIRCRAFT IN CRUISE PHASE ENABLING TRAJECTORY OPTIMIZATION

Transport ◽  
2020 ◽  
Vol 35 (1) ◽  
pp. 87-97
Author(s):  
Małgorzata Pawlak ◽  
Andrzej Majka ◽  
Michal Kuzniar ◽  
Jowita Pawluczy
Keyword(s):  
Trajectory Optimization ◽  
Global Climate ◽  
Air Transport ◽  
Jet Engines ◽  
Grid Graph ◽  
Continuous Increase ◽  
Jet Engine ◽  
Passenger Aircraft ◽  
Fuel Consumption And Emissions ◽  
Intensive Development

Nowadays, air transport is the most modern and the most dynamically developing branch of transport. This intensive development of air transport causes the continuous increase in emissions of pollutants, mainly greenhouse gases, leading to the deepening of the greenhouse effect, which in turn leads to irreversible global climate change. In order to optimize air communication and make it even more economical and environmentally friendly, such activities as e.g. SESAR project are undertaken. One of the parts of this project is the research on minimizing fuel consumption and emissions of pollutants in jet engine exhausts. The paper presents a developed model of emission and main pollutants (NOx, CO, HC and CO2) in the exhausts of jet engines of a passenger aircraft during a cruise phase. Applying simple optimization tools, such as e.g. the Dijkstra’s algorithm, this model was verified by the optimization of a trajectory of a jet aircraft in a cruise phase on an exemplary route in terms of minimizing emission of selected harmful compounds in jet engines exhausts. To meet the aim of the research, it was necessary to develop a computer program that determines a two-dimensional grid graph, assigns its appropriate weights to its edges and passing along these edges, determines the optimal trajectory of a given flight between two indicated start and end vertices. The developed research methodology is universal and can be applied for any jet passenger aircraft.

Exergy analysis of a turboprop engine at different flight altitude and speeds using novel consideration

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Ali Dinc ◽  
Yousef Gharbia
Keyword(s):  
Fuel Consumption ◽  
Thermal Efficiency ◽  
Exergy Efficiency ◽  
Specific Fuel Consumption ◽  
Flight Altitude ◽  
Fuel Flow ◽  
Turboprop Engine ◽  
Shaft Power ◽  
Two Parameters ◽  
The Relationship

Abstract In this study, exergy efficiency calculations of a turboprop engine were performed together with main performance parameters such as shaft power, specific fuel consumption, fuel flow, thermal efficiency etc., for a range of flight altitude (0–14 km) and flight speeds (0–0.6 Mach). A novel exergy efficiency formula was derived in terms of specific fuel consumption and it is shown that these two parameters are inversely proportional to each other. Moreover, a novel exergy efficiency and thermal efficiency relation was also derived. The relationship showed that these two parameters are linearly proportional to each other. Exergy efficiency of the turboprop engine was found to be in the range of 23–33%. Thermal efficiency of the turboprop engine was found to be around 25–35%. Exergy efficiency is higher at higher speeds and altitude where the specific fuel consumption is lower. Conversely, exergy efficiency of the engine is lower for lower speeds and altitude where the specific fuel consumption is higher.

Determination of the flight trajectory in terms of emission and fuel consumption minimization

2021 ◽  
pp. 095441002110122
Author(s):  
Małgorzata Pawlak ◽  
Michał Kuźniar ◽  
Andrzej R. Majka
Keyword(s):  
Fuel Consumption ◽  
Negative Impact ◽  
Weather Conditions ◽  
Air Transport ◽  
Cycle Phase ◽  
Horizontal Flight ◽  
Pollutants Emission ◽  
Aircraft Trajectory ◽  
Air Speed ◽  
Constant Altitude

The present-day world is characterized by the intense development of air transport. However, along with it, significant problems appear. Among these problems, the most important are those relating to safety and negative impact of air transport on the environment. Air transport efficiency and profitability issues, although not critical, must also be taken into account because they decide about the intensity of development of this branch of transport. There are currently two large programs in Europe oriented at improving safety, environmental, and efficiency indicators. These are SESAR 2020 and Clean Sky 2, being a continuation of previous ones. One of the ways to reduce negative impact of air transport on the environment and improve its efficiency is to reduce fuel consumption and pollutants emissions resulting from fuel combustion. To find solutions with the abovementioned features, it is necessary to have sufficiently accurate models to estimate the amount of fuel consumed and the amount of pollutants emitted. Developing a sufficiently accurate model to determine fuel consumption and pollutants emission was performed. Due to the specificity of the missions carried out by passenger aircraft, the focus was on the cruise stage when aircraft flies at a constant altitude with a constant air speed. The result of the analysis was the development of methodology for fuel consumption and emission of main pollutants in cruise conditions. Specific fuel consumption is calculated for the thrust required for horizontal flight at cruising altitude. Emission indexes for CO, NOx, HC, and CO2 for the cruise have been determined based on known indexes for the landing and take-off cycle phase, after applying appropriate corrections. An illustration of the application of the developed methodology was the optimization of a medium-sized transport aircraft trajectory on a selected connection to determine a trajectory characterized by a minimum emission value taking into account weather conditions.

Two-Stroke Marine Diesel Engine Variable Injection Timing System Performance Evaluation and Optimum Setting for Minimum Fuel Consumption at Acceptable NOx Levels

2014 ◽  
Author(s):  
Dimitrios T. Hountalas ◽  
Spiridon Raptotasios ◽  
Antonis Antonopoulos ◽  
Stavros Daniolos ◽  
Iosif Dolaptzis ◽  
...  
Keyword(s):  
Diesel Engine ◽  
Fuel Consumption ◽  
Engine Performance ◽  
Operating Conditions ◽  
Specific Fuel Consumption ◽  
Injection Timing ◽  
Nox Emissions ◽  
Pressure Measurements ◽  
Cylinder Pressure ◽  
Start Of Injection

Currently the most promising solution for marine propulsion is the two-stroke low-speed diesel engine. Start of Injection (SOI) is of significant importance for these engines due to its effect on firing pressure and specific fuel consumption. Therefore these engines are usually equipped with Variable Injection Timing (VIT) systems for variation of SOI with load. Proper operation of these systems is essential for both safe engine operation and performance since they are also used to control peak firing pressure. However, it is rather difficult to evaluate the operation of VIT system and determine the required rack settings for a specific SOI angle without using experimental techniques, which are extremely expensive and time consuming. For this reason in the present work it is examined the use of on-board monitoring and diagnosis techniques to overcome this difficulty. The application is conducted on a commercial vessel equipped with a two-stroke engine from which cylinder pressure measurements were acquired. From the processing of measurements acquired at various operating conditions it is determined the relation between VIT rack position and start of injection angle. This is used to evaluate the VIT system condition and determine the required settings to achieve the desired SOI angle. After VIT system tuning, new measurements were acquired from the processing of which results were derived for various operating parameters, i.e. brake power, specific fuel consumption, heat release rate, start of combustion etc. From the comparative evaluation of results before and after VIT adjustment it is revealed an improvement of specific fuel consumption while firing pressure remains within limits. It is thus revealed that the proposed method has the potential to overcome the disadvantages of purely experimental trial and error methods and that its use can result to fuel saving with minimum effort and time. To evaluate the corresponding effect on NOx emissions, as required by Marpol Annex-VI regulation a theoretical investigation is conducted using a multi-zone combustion model. Shop-test and NOx-file data are used to evaluate its ability to predict engine performance and NOx emissions before conducting the investigation. Moreover, the results derived from the on-board cylinder pressure measurements, after VIT system tuning, are used to evaluate the model’s ability to predict the effect of SOI variation on engine performance. Then the simulation model is applied to estimate the impact of SOI advance on NOx emissions. As revealed NOx emissions remain within limits despite the SOI variation (increase).

Characteristics of Water-in-Diesel Emulsions in a Single Cylinder Compression Ignition Engine

2014 ◽  
Author(s):  
Teja Gonguntla ◽  
Robert Raine ◽  
Leigh Ramsey ◽  
Thomas Houlihan
Keyword(s):  
Fuel Consumption ◽  
Direct Injection ◽  
Engine Performance ◽  
Operating Conditions ◽  
Specific Fuel Consumption ◽  
Brake Specific Fuel Consumption ◽  
Compression Ignition Engine ◽  
Oil Emulsion ◽  
Single Cylinder ◽  
Performance And Emission

The objective of this project was to develop both engine performance and emission profiles for two test fuels — a 6% water-in-diesel oil emulsion (DOE-6) fuel and a neat diesel (D100) fuel. The testing was performed on a single cylinder, direct-injection, water-cooled diesel engine coupled to an eddy current dynamometer. Output parameters of the engine were used to calculate Brake Specific Fuel Consumption (BSFC) and Engine Efficiency (η) for each test fuel. DOE-6 fuels generated a 24% reduction in NOX and a 42% reduction in Carbon Monoxide emissions over the tested operating conditions. DOE-6 fuels presented higher ignition delays — between 1°-4°, yielded 1%–12% lower peak cylinder pressures and produced up to 5.5% lower exhaust temperatures. Brake Specific Fuel consumption increased by 6.6% for the DOE-6 fuels as compared to the D100 fuels. This project is the first research done by a New Zealand academic institution on water-in-diesel emulsion fuels.

An Improvement of Part Load Performance of Diesel Engines Operating at Constant Speed Conditions

1994 ◽  
Vol 208 (1) ◽  
pp. 21-25 ◽  
Author(s):  
A A Abdel-Rahman ◽  
M K Ibrahim ◽  
A A Said
Keyword(s):  
Fuel Consumption ◽  
Diesel Engines ◽  
Petroleum Refining ◽  
Specific Fuel Consumption ◽  
Constant Speed ◽  
Maximum Pressure ◽  
Brake Specific Fuel Consumption ◽  
Part Load ◽  
Generating Sets ◽  
In Series

This paper discusses the possibility of improving the part load performance of diesel electric turbocharged engines operating at constant speed conditions. A sequential turbocharged system is proposed, where the compressors are connected In series. The study focused on two turbocharged diesel–electric generating sets existing at Ameria Petroleum Refining Company in Alexandria, Egypt. The results of the prediction showed that, at part load, both the maximum pressure and temperature were increased, and the brake specific fuel consumption was reduced considerably (by about 10 per cent).

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