A Review on the Role and Impact of Typical Alcohol Additives in Controlling Emissions from Diesel Engines

Today, most of the essential energy needs of humans and production are met by fossil fuels that are expected to be exhausted in the next century. Furthermore, fossil fuels are not renewable and sensitive to the environment. In particular, there is growing concerned about the negative impact of internal combustion engine emissions on climate change and global environmental pollution. Fuel and alcohol-based additives are being considered as good candidates for sustainable alternative fuels used on compression ignition engines. In this review, the different key production pathways and properties of each of the five alcohol additive candidates were discussed. Besides, their effects on the emission characteristics of diesel engines when alcohol additives are added to diesel fuel are also carefully considered. Five candidates including methanol, ethanol, propanol, butanol, and pentanol have been shown to control pollutants from combustion engines while using alcohol-based additives. This is of great significance in the strategy of coping with the threats of pollution and climate change caused by the operation of transport vehicles

High-Speed Infrared Measurement of Injector Tip Temperature during Diesel Engine Operation

Pre-catalyst engine emissions and detrimental injector deposits have been widely associated with the near-nozzle fluid dynamics during and after the injection events. Although the heating and evaporation of fuel films on the nozzle surface directly affects some of these processes, there are no experimental data for the transient evolution of nozzle surface temperature during typical engine conditions. In order to address this gap in knowledge, we present a non-intrusive approach for the full-cycle time resolved measurement of the surface temperature of production nozzles in an optical engine. A mid-wave infrared high-speed camera was calibrated against controlled conditions, both out of engine and in-engine to account for non-ideal in surface emissivity and optical transmissivity. A custom-modified injector with a thermocouple embedded below the nozzle surface was used to validate the approach under running engine conditions. Calibrated infrared thermography was then applied to characterise the nozzle temperature at 1200 frames per second, during motored and fired engine operation, thus revealing for the first time the effect of transient operating conditions on the temperature of the injector nozzle’s surface.

A Study on the Effect of Ignition Timing on Residual Gas, Effective Release Energy, and Engine Emissions of a V-Twin Engine

The ignition timing of an SI engine is a critical parameter. The influence on residual gas, effective release energy, and emissions characteristics of ignition timing for the V-twin engine is investigated in this research. For this purpose, an experiment system was built with a dynamometer, and a model of the simulation was created. In this research, the ignition timing was varied from 10 to 45 degrees BTDC under full load operating conditions, with engine speeds ranging from 3000 to 10,000 rpm. Based on the output data, ignition timing has a major impact on the proportion of residual gas, efficient release energy, performance of the engine, and the emission characteristics. The smallest proportion of residual gas was 0.07% at 8000 rpm and ignition timing of 10 °CA. At 15 °CA of ignition timing, the highest efficient release energy was 0.817 kJ at 4000 rpm, while at 8000 rpm and 25 °CA of ignition timing, it was 0.8305 kJ. At 6000 rpm, the greatest braking torque of the engine was 21.57 Nm, while the minimal BSFC was 343.821 g/kWh. The nitrogen oxide emission and HC emission increase with the advanced ignition timing, but CO emission decreases.

Air Quality Studies at Ukrainian Airports

Sustainability of aviation must be provided to limit the harmful influence and protect public health and the environment. As a rule, national and international regulations aim to reduce ambient air pollution from the aviation sector. Ukraine and other countries have historically adopted international regulations concerning air quality to protect public health and the natural environment. Local regulations also regulate it. However, these documents cover mainly stationary emission sources. In contrast, mobile sources, especially aircraft, are not considered, although, unlike most transportation modes, aircraft travel great distances at various altitudes, generating emissions that potentially impact air quality. This paper was aimed to study the principles and methods to monitor air pollution from aircraft engines at main airports of Europe, north America, and Asia. Based on measurement campaign analysis at some airports of the world and modelling results by complex model PolEmiCa (Pollution and Emission Calculation), the method and technical characteristics for measurement system detect the aircraft engine emissions. The developed practical recommendations were realised at Ukrainian airports and used for validation of model PolEmiCa. Thus, the modelling results for each engine are in good agreement with the results of measurements by the AC32M Nitrogen Oxides (NOX) analyser system due to considering the jet and plume-regime during an experimental investigation at Boryspol airport. Analysis of measured instantaneous concentration demonstrates a high correlation with the runway movements and take-off at Zhulyany airport.