Mark Veinblat

Performance Analysis of SI Engine Fueled by Ethanol Steam Reforming Products

The goal of the present work was to analyze the performance of a spark ignition engine fueled by ethanol steam reforming products. The highest reformer-ICE system efficiency and the lowest CO emissions were achieved with the ethanol steam reforming products obtained at reaction temperature of 1000K and water/ethanol ratio of 1.8. Fueling the SI engine with reformate gas made it possible to achieve the reformer-ICE system efficiency of 40% for the engine fed by SRE products compared with 34% for gasoline and 36% for ethanol. CO emissions were reduced by 3.5 and 10 times compared with ethanol and gasoline, respectively. NOx emissions were decreased by about 4 times compared with the gasoline fed engine.

Simulation of Wankel Engine Performance Using Commercial Software for Piston Engines

At present the market of Wankel engines is limited to some special applications. This fact explains absence of commercial software products specially developed for this engine simulation and prediction of its performance. Conversely, there are available and widely used software products for simulation of reciprocating-piston engines performance. Some attempts are known in using this software for prediction of Wankel engine performance. This paper details an approach used in these attempts. Main differences between both types of engines are summarized and principles of a virtual reciprocating-piston engine compilation are developed. A method of virtual blowing was developed for assessment of discharge coefficients for intake and exhaust ports. Comparison of simulation results with the measured performance of two UAV Wankel engines showed sufficient accuracy of the suggested approach.

Fuel Effects on Emissions from Heavy-Duty Diesel Engines – Results of Recent Research Programs

The main goal of the work presented here was to compile a review of the available literature on the effects of diesel fuel properties on emissions from heavy-duty diesel engines (HDDEs). Because of the large number of various studies that have been performed in this area, the present review is mainly based on the most comprehensive recent research programs: the European Programme on Emissions, Fuels and Engine Technologies (EPEFE), and the USA Programs EPA Heavy-Duty Engine Working Group (EPA-HDEWG) and Diesel Emission Control – Sulfur Effect (DECSE). Fuel properties that have been identified over the years as influencing emissions from HDDEs, and were considered in this work, are cetane number, density, aromatics (total and poly-), sulfur and oxygen contents and back-end distillation. The impact of fuel sulfur content on emission control systems was reviewed, based mainly on the findings of the latest DECSE Program, which was concluded in 2000. These systems include diesel oxidation catalysts, lean-NOx catalysts, NOx adsorbers and diesel particulate filters (traps). A comparison is presented between the regression models, developed in the framework of the EPEFE and EPA-HDEWG programs. Only limited data are available addressing oxygen effects on HDDE emissions. It is noted that there is still lack of data regarding the fuel effects on emissions of engines tested over the new European Transient Cycle.

Thermo-Chemical Recuperation as an Efficient Way of Engine's Waste Heat Recovery

It is known that about 30% of fuel energy introduced to an internal combustion engine (ICE) is wasted with engine exhaust gases. One of the promising ways of waste heat recovery is thermo-chemical recuperation (TCR). For the purpose of TCR realization, in principle any fuel may be used. However, utilization of renewable bio-alcohols, especially ethanol or methanol is the most favorable. The advantages of TCR over turbocharging are in the fact that its energy transfer is not limited by isentropic expansion and that the reforming process improves the fuel properties. A comprehensive theoretical analysis of the ICE with TCR was carried out using the developed model for simulation of the joint operation of ICE with alcohol reformer, when the ICE is fed by the alcohol reforming products and the energy of the exhaust gases is utilized to sustain endothermic reforming reactions. Simulation results show that it is possible to sustain endothermic reforming reactions with a reasonable reactor size. Modeling results point out a possibility of engines efficiency improvement by up to 13% in comparison with ICE feeding by gasoline together with achievement of zero-impact pollutant emissions.