scholarly journals Assessment of the Effect of Environmental Conditions on Rotorcraft Pollutant Emissions at Mission Level

2017 ◽  
Author(s):  
Jesus Ortiz-Carretero ◽  
Alejandro Castillo Pardo ◽  
Vassilios Pachidis ◽  
Ioannis Goulos
Keyword(s):  
Environmental Conditions ◽  
Engine Performance ◽  
Pollutant Emissions ◽  
Civil Aviation ◽  
Ambient Conditions ◽  
Engine Operation ◽  
Helicopter Rotors ◽  
Helicopter Flight ◽  
Fuel Burn

It is anticipated that the contribution of rotorcraft activities to the environmental impact of civil aviation will increase in the forthcoming future. Due to their versatility and robustness, helicopters are often operated in harsh environments with extreme ambient conditions and dusty air. These severe conditions affect not only the engine operation but also the performance of helicopter rotors. This impact is reflected in the fuel burn and pollutants emitted by the helicopter during a mission. The aim of this paper is to introduce an exhaustive methodology to quantify the influence of the environment in the mission fuel consumption and the associated emissions of nitrogen oxides (NOx). An Emergency Medical Service (EMS) and a Search and Rescue (SAR) mission were used as a case study to simulate the effects of extreme temperatures, high altitude and compressor degradation on a representative Twin-Engine Medium (TEM) weight helicopter, the Sikorsky UH-60A Black Hawk. A simulation tool for helicopter mission performance analysis developed and validated at Cranfield University was employed. This software comprises different modules that enable the analysis of helicopter flight dynamics, powerplant performance and exhaust emissions over a user defined flight path profile. The results obtained show that the environmental effects on mission fuel and emissions are mainly driven by the modification of the engine performance for the particular missions simulated. Fluctuations as high as 12% and 40% in mission fuel and NOx emissions, respectively, were observed under the environmental conditions simulated in the present study.

scholarly journals Impact of Adverse Environmental Conditions on Rotorcraft Operational Performance and Pollutant Emissions

2017 ◽  
Vol 140 (2) ◽  
Author(s):  
Jesus Ortiz-Carretero ◽  
Alejandro Castillo Pardo ◽  
Ioannis Goulos ◽  
Vassilios Pachidis
Keyword(s):  
Engine Performance ◽  
Pollutant Emissions ◽  
Operational Performance ◽  
Civil Aviation ◽  
Harsh Environments ◽  
Nox Emissions ◽  
Ambient Conditions ◽  
Helicopter Flight ◽  
Fuel Burn ◽  
Adverse Environmental Conditions

It is anticipated that the contribution of rotorcraft activities to the environmental impact of civil aviation will increase in the future. Due to their versatility and robustness, helicopters are often operated in harsh environments with extreme ambient conditions. These severe conditions not only affect the performance of the engine but also affect the aerodynamics of the rotorcraft. This impact is reflected in the fuel burn and pollutants emitted by the rotorcraft during a mission. The aim of this paper is to introduce an exhaustive methodology to quantify the influence adverse environment conditions have in the mission fuel consumption and the associated emissions of nitrogen oxides (NOx). An emergency medical service (EMS) and a search and rescue (SAR) mission are used as case studies to simulate the effects of extreme temperatures, high altitude, and compressor degradation on a representative twin-engine medium (TEM) weight helicopter, the Sikorsky UH-60A Black Hawk. A simulation tool for helicopter mission performance analysis developed and validated at Cranfield University was employed. This software comprises different modules that enable the analysis of helicopter flight dynamics, powerplant performance, and exhaust emissions over a user-defined flight path profile. For the validation of the models implemented, extensive comparisons with experimental data are presented throughout for rotorcraft and engine performance as well as NOx emissions. Reductions as high as 12% and 40% in mission fuel and NOx emissions, respectively, were observed for the “high and cold” scenario simulated at the SAR role relative to the same mission trajectory under standard conditions.

System Level Performance and Emissions Evaluation of Renewable Fuels for Jet Engines

2014 ◽  
Author(s):  
Kadambari Lokesh ◽  
Vishal Sethi ◽  
Theoklis Nikolaidis ◽  
Devaiah Karumbaiah
Keyword(s):  
Engine Performance ◽  
Operating Conditions ◽  
System Level ◽  
Civil Aviation ◽  
Jet Engines ◽  
Stirred Reactor ◽  
Fuel Burn ◽  
Performance And Emissions ◽  
Aircraft Performance ◽  
Level Performance

Incessant demand for fossil derived energy and the resulting environmental impact has urged the renewable energy sector to conceive one of the most anticipated sustainable, alternative “drop-in” fuels for jet engines, called as, Bio-Synthetic Paraffinic Kerosene (Bio-SPKs). Second (Camelina SPK & Jatropha SPK and third generation (Microalgae SPK) advanced biofuels have been chosen to analyse their influence on the behaviour of a jet engine through numerical modelling and simulation procedures. The thermodynamic influence of each of the biofuels on the gas turbine performance extended to aircraft performance over a user-defined trajectory (with chosen engine/airframe configuration) have been reported in this paper. Initially, the behaviour of twin-shaft turbofan engine operated with 100% Bio-SPKs at varying operating conditions. This evaluation is conducted from the underpinning phase of adopting the chemical composition of Bio-SPKs towards an elaborate and careful prediction of fluid thermodynamics properties (FTPs). The engine performance was primarily estimated in terms of fuel consumption which steers the fiscal and environmental scenarios in civil aviation. Alternative fuel combustion was virtually simulated through stirred-reactor approach using a validated combustor model. The system-level emissions (CO2 and NOx) have been numerically quantified and reported as follows: the modelled aircraft operating with Bio-SPKs exhibited fuel economy (mission fuel burn) by an avg. of 2.4% relative to that of baseline (Jet Kerosene). LTO-NOx for the user-defined trajectory decreased by 7–7.8% and by 15–18% considering the entire mission. Additionally, this study reasonably qualitatively explores the benefits and issues associated with Bio-SPKs.

scholarly journals Benchmarking data from the experience gained in engine performance and emissions testing on alternative fuels for aviation

2017 ◽  
Vol 1 ◽  
pp. S5WGLD ◽  
Author(s):  
Wajid A. Chishty ◽  
Tak Chan ◽  
Pervez Canteenwalla ◽  
Craig R. Davison ◽  
Jennifer Chalmers
Keyword(s):  
Energy Security ◽  
Alternative Fuels ◽  
National Research Council ◽  
Engine Performance ◽  
Performance Testing ◽  
Air Pollutant ◽  
Pollutant Emissions ◽  
Engine Operation ◽  
Commercial Aviation ◽  
Performance And Emissions

Abstract Alternative fuel for aviation has been the centre of serious focus for the last decade, owing mostly to the challenges posed by the price of conventional petroleum fuel, energy security and environmental concerns. The downslide in the oil prices in the recent months and the fact that energy security is not considered a major threat in commercial aviation, these factors have worked negatively for the promotion of alternative fuels. However, the continuous commitment to environmental stewardship by Governments and the industry have kept the momentum going towards the transparent integration of renewable alternatives in the aviation market. On the regulatory side, much progress have been made in the same timeframe with five alternative fuels being certified as synthetic blending components for aviation turbine fuels for use in civil aircraft and engines. Another seven alternative fuels are in the various stages of certification protocol. This progress has been made possible because of the extensive performance testing, both at full engine conditions and at engine components level. This article presents the results of engine performance and air pollutant emissions measurements gathered from the alternative fuels qualification testing conducted at the National Research Council Canada over the last seven years. This benchmarking data was collected on various engine platforms at full engine operation at sea level and/or altitude conditions using a variety of aviation alternative fuels and their blends. In order to provide a reference comparison basis, the results collected using the alternative fuels are compared with baseline Jet-A1 or JP-8 conventional fuels.

Modelling and Assessment of Compressor Faults on Marine Gas Turbines

2012 ◽  
Author(s):  
I. Roumeliotis ◽  
N. Aretakis ◽  
K. Mathioudakis ◽  
E. A. Yfantis
Keyword(s):  
Gas Turbines ◽  
Engine Performance ◽  
Performance Model ◽  
Operating Conditions ◽  
Pollutant Emissions ◽  
Maximum Speed ◽  
Performance Modelling ◽  
Engine Operation ◽  
Marine Propulsion ◽  
And Performance

Any prime mover exhibits the effects of wear and tear over time, especially when operating in a hostile environment. Marine gas turbines operation in the hostile marine environment results in the degradation of their performance characteristics. A method for predicting the effects of common compressor degradation mechanisms on the engine operation and performance by exploiting the “zooming” feature of current performance modelling techniques is presented. Specifically a 0D engine performance model is coupled with a higher fidelity compressor model which is based on the “stage stacking” method. In this way the compressor faults can be simulated in a physical meaningful way and the overall engine performance and off design operation of a faulty engine can be predicted. The method is applied to the case of a twin shaft engine, a configuration that is commonly used for marine propulsion. In the case of marine propulsion the operating profile includes a large portion of off-design operation, thus in order to assess the engine’s faults effects, the engine operation should be examined with respect to the marine vessel’s operation. For this reason, the engine performance model is coupled to a marine vessel’s mission model that evaluates the prime mover’s operating conditions. In this way the effect of a faulty engine on vessels’ mission parameters like overall fuel consumption, maximum speed, pollutant emissions and mission duration can be quantified.

Analysis of the Combustion Process in a EURO III Heavy-Duty Direct Injection Diesel Engine

2002 ◽  
Vol 124 (3) ◽  
pp. 636-644 ◽  
Author(s):  
J. M. Desantes ◽  
J. V. Pastor ◽  
J. Arre`gle ◽  
S. A. Molina
Keyword(s):  
High Speed ◽  
Direct Injection ◽  
Combustion Process ◽  
Engine Performance ◽  
Injection Pressure ◽  
Pollutant Emissions ◽  
Injection Timing ◽  
Engine Operation ◽  
Operation Conditions ◽  
Representative Points

To fulfill the commitments of future pollutant regulations, current development of direct injection (DI) Diesel engines requires to improve knowledge on the injection/combustion process and the effect of the injection parameters and engine operation conditions upon the spray and flame characteristics and how they affect engine performance and pollutant emissions. In order to improve comprehension of the phenomena inherent to Diesel combustion, a deep experimental study has been performed in a single-cylinder engine with the main characteristics of a six-cylinder engine passing the EURO III legislation. Some representative points of the 13-mode engine test cycle have been considered modifying the nominal values of injection pressure, injection load, intake pressure, engine speed, and injection timing. The study combines performance and emissions experimental measurements together with heat release law (HRL) analysis and high-speed visualization. Controlling parameters for BSFC, NOx, and soot emissions are identified in the last part of the paper.

scholarly journals Analysis of the Driving Altitude and Ambient Temperature Impact on the Conversion Efficiency of Oxidation Catalysts

2021 ◽  
Vol 11 (3) ◽  
pp. 1283
Author(s):  
José Ramón Serrano ◽  
Pedro Piqueras ◽  
Enrique José Sanchis ◽  
Bárbara Diesel
Keyword(s):  
Ambient Temperature ◽  
Conversion Efficiency ◽  
Mass Flow ◽  
Engine Performance ◽  
Oxidation Catalyst ◽  
Ambient Conditions ◽  
Engine Operation ◽  
Temperature Impact ◽  
Conversion Efficiencies ◽  
The Impact

Worldwide emission standards are extending their requirements to cover engine operation under extreme ambient conditions and fill the gap between the type-approval and real driving conditions. The new ambient boundaries affect the engine performance and raw emissions as well as the efficiency of the exhaust aftertreatment systems. This study evaluates the impact of high altitude and low ambient temperature on the light-off temperature and conversion efficiency of an oxidation catalyst. The results are compared in a common range of exhaust mass flow and temperature with the baseline sea-level operation at 20 °C. A reduction of CO and HC conversion efficiencies was found at 2500 m and −7 °C, with a relevant increase of the light-off temperature for both of the pollutants. The analysis of the experimental data was complemented with the use of a catalyst model to identify the causes leading to the deterioration of the CO and HC light-off. The use of the model allowed for identifying, for the same exhaust mass flow and temperature, the contributions to the variation of conversion efficiency caused by the change in engine-out emissions and tailpipe pressure, which are, in turn, manifested in the variation of the reactants partial pressure and dwell time as governing parameters.

scholarly journals Simultaneous measurements of radon, thoron and equilibrium equivalent concentrations in family house - single case study

2019 ◽  
Vol 34 (2) ◽  
pp. 181-188
Author(s):  
Robert Lakatos ◽  
Sofija Forkapic ◽  
Vanja Radolic ◽  
Igor Celikovic ◽  
Selena Samardzic ◽  
...  
Keyword(s):  
Environmental Conditions ◽  
Single Case ◽  
Detector System ◽  
Dose Assessment ◽  
Single Case Study ◽  
Ambient Conditions ◽  
Arithmetic Means ◽  
Simultaneous Measurements ◽  
Family House

Simultaneous indoor measurements of radon, thoron and equilibrium equivalent con centrations, by three different continuous radon monitors in real ambient conditions, were performed and compared during two weeks period. Radon concentrations varied from 153 Bqm?3 to 870 Bqm?3 with variations of thoron concentrations in the range (2.17-219) Bqm?3. Obtained arithmetic means of equilibrium equivalent radon and thoron concentrations were (130 ? 50) Bqm?3 and (23 ? 18) Bqm?3, respectively. The inter-comparison of active radon de vices was focused on consistency of results between them selves and the influence of environmental conditions on the behavior of each detector system. The obtained statistically significant correlation between the results of used monitors, validates them for application in radon diagnostic measurements as the first step in radon remediation and dose assessment.

scholarly journals CFD Analysis of a Large Marine Engine Scavenging Process

Processes ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 141
Author(s):  
Tomislav Senčić ◽  
Vedran Mrzljak ◽  
Vedran Medica-Viola ◽  
Igor Wolf
Keyword(s):  
Engine Performance ◽  
Passive Scalar ◽  
Trapping Efficiency ◽  
Pollutant Emissions ◽  
Delivery Ratio ◽  
Engine Operation ◽  
Marine Diesel ◽  
Operation Parameters ◽  
Scavenging Efficiency ◽  
Charging Efficiency

The scavenging process is an important part of the two-stroke engine operation. Its efficiency affects the global engine performance such as power, fuel consumption, and pollutant emissions. Slow speed marine diesel engines are uniflow scavenged, which implies inlet scavenging ports on the bottom of the liner and an exhaust valve on the top of the cylinder. A CFD model of such an engine process was developed with the OpenFOAM software tools. A 12-degree sector of the mesh was used corresponding to one of the 30 scavenging ports. A mesh sensitivity test was performed, and the cylinder pressure was compared to experimental data for the analyzed part of the process. The scavenging performances were analyzed for real operation parameters. The influence of the scavenge air pressure and inlet ports geometric orientation was analyzed. The scavenging process is analyzed by means of a passive scalar representing fresh air in the cylinder. Isosurfaces that show the concentration of fresh air were presented. The variation of oxygen and carbon dioxide with time and the axial and angular momentum in the cylinder were calculated. Finally, the scavenging performance for the various operation parameters was evaluated by means of scavenging efficiency, charging efficiency, trapping efficiency, and delivery ratio. It was found that the scavenging efficiency decreases with the engine load due to the shorter time for the process. The scavenging efficiency increases with the pressure difference between the exhaust and scavenging port, and the scavenging efficiency decreases with the increase in the angle of the scavenging ports. It was concluded that smaller angles than the industry standard of 20° could be beneficial to the scavenging efficiency. In the investigation, the charging efficiency ranged from 0.91 to over 0.99, the trapping efficiency ranged from 0.54 to 0.83, the charging efficiency ranged from 0.78 to 0.92, and the delivery ratio ranged from 1.21 to 2.03.

Influence of Fuel on a Valveless Pulsejet Engine Performance and Pollutant Emissions

2019 ◽  
Author(s):  
Andreia Melo ◽  
Francisco Brójo
Keyword(s):  
Engine Performance ◽  
Pollutant Emissions ◽  
Civil Aviation ◽  
Ansys Fluent ◽  
Fuel Mass ◽  
Pollutant Formation ◽  
Fuel Flow ◽  
Mass Flows ◽  
Construction Operation ◽  
Made In

Abstract In this work the performance of a valveless pulsejet with two different fuels and several fuel mass flows was numerically estimated. Results for pressures, velocities, traction and pollutant formation are presented. Even though this type of engine has many advantages over the conventional types, it still has many problems for application in civil aviation due to noise levels. Although having a very simple construction, operation is not completely understood, so studies continue to be made in order to have a better knowledge of the physics behind operation. For engine sizing, was performed a calculation procedure based on data of existing engines and equations reported in the literature. The pulsejet operation was then simulated using ANSYS Fluent 16.2. Simulations were 2D transient, three different fuel flows were analysed: 0.04 kg/s, 0.06 kg/s and 0.1 kg/s and two fuels used: propane and methane. For propane an additional case was defined, being the fuel mass flow of 0.12 kg/s. The results obtained are similar for the two fuels, the variables have the same behaviour with the variation of the fuel flow except for the operating frequency.

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