Industrial Diesel Engines Research Articles

A study on knocking monitoring system for efficient energy management of industrial CRDI engine

In order to meet the enhancing exhaust gas regulations, we need to solve the industrial CRDI diesel engine's knocking problem which causes environmental pollutions. Knocking is one of the causes that produce exhaust gas as well as serious damage to engines. In case of an industrial vehicle, the existing knocking sensor cannot guarantee the accuracy due to the problem in the working environment. Therefore, this study aims to develop a knocking discrimination emulator for the industrial CRDI engine in order to discriminate knocking and defective cylinder by using crankshaft's angular speed. We have implemented the knocking diagnostic algorithm that enables knocking discrimination and engine balance correction applicable to the ECU exclusively to the common rail engine on the emulator. The development of the emulator has enabled to adjust fuel injection timing and amount of fuel. Thus, this study aims to improve engine efficiency and to reduce emissions.

産業用ディーゼルの最新技術動向(<メカライフ特集>合のものづくり)

産業用ディーゼルの最新技術動向(<メカライフ特集>合のものづくり)

Combustion Characteristics and Emissions Reduction of Small Industrial Diesel Engine

Combustion Characteristics and Emissions Reduction of Small Industrial Diesel Engine

Development Methodology for Industrial Diesel Engines

Development Methodology for Industrial Diesel Engines

645 クランク軸曲げ振りダンパーによるエンジン騒音低減

As the industrial diesel engine has the gear train to drive injection pump and valve system, engine noise is induced by the gear impact at the idling condition. Furthermore, gear impact noise is increased by the torsional vibration of the crankshaft. In this paper, numerical model of the torsional and bending damper for crankshaft is added to the total analytical system to predict the vibratory response and radiated noise of the engine block coupled with the rotating crankshaft and gear trains. The effects of the torsional and bending damper with scarce and sufficient damping to reduce the gear impact force, main bearing forces and engine block vibration are discussed.

Dissociative Adsorption of O2 on Clean and CO-Precovered Pt Surfaces

ABSTRACTIt is generally accepted that CO oxidation on transition metals follows a Langmuir-Hinshelwood mechanism. The oxidation reaction takes place in two sequential steps where the oxygen molecule first dissociates into atomic oxygen and then reacts with an adsorbed CO to form CO2. One critical question concerning the reaction kinetics under high pressure is the probability of oxygen dissociation on a highly CO covered surface. On bare transition metal surfaces, molecularly adsorbed oxygen readily dissociates with little or no apparent activation barrier. In industrial diesel engine catalysis, the metal surface is initially packed with CO. Subsequent reactions such as oxygen dissociation must take place on a CO covered surface. In this paper, we performed density functional theory (DFT) calculations for O2 dissociation on Pt(111) in the presence of different CO adsorption environments. While several stable O2 molecular precursor states (top-bridge-top, top-fcc-bridge, and top-hcp-bridge) exist on a clean Pt(111) surface, these precursors become endothermic beyond a critical CO coverage of ∼0.44 ML. Furthermore, the reaction path for CO oxidation via dissociated atomic oxygen becomes less favorable at higher CO coverage, primarily due to competitive adsorption and lateral repulsion. It was found that the oxygen dissociation barrier and the binding energies of atomic oxygen are well correlated via the Evans-Polanyi relationship.

POLYCYCLIC AROMATIC HYDROCARBONS IN ATMOSPHERIC DEPOSITIONS AROUND THE VENICE LAGOON

Studies have revealed the potential risks to which human health and ecosystems are exposed in the Venice Lagoon, due to the atmospheric deposition of persistent pollutants such as trace metals and organic compounds. A total of 77 atmospheric bulk deposition samples were collected monthly from April 2002 to December 2004, from three sites located in the cities of Mestre and Venice, and inside the industrial area of Porto Marghera. Samples were analyzed by HRGC/HRMS for polycyclic aromatic hydrocarbon (PAH) content. Spatial variations of atmospheric fallout were investigated, and source identification was attempted using diagnostic ratios and multivariate statistical analysis. Different conditions were recorded, with three anthropic signatures: i) industrial, mainly affected by local industrial sources and diesel engine emissions, ii) urban, mostly influenced by high traffic density, especially petrol car emissions and iii) lagoonal, characterized by diesel emissions from boat engines and oil burning, with random transport of industrial emissions.

Influence of biofuels on exhaust gas and noise emissions of small industrial diesel engines

At small industrial diesel engines, as they were brought in oftenly on building sites, in the farming and forest industry and on boats, biofuels are increasingly used. In a research project of the University of Applied Sciences Jena, Germany, thus the changes of the exhaust gas pollutant and noise emissions of these diesel engines were investigated. Test fuels were diesel fuel, and also biofuels as biodiesel (RME), rape seed oil and sun flower oil. Depending on the operating point these biofuels increased or reduced the emissions of exhaust gas and noise of the investigated engines clearly.

Crankshaft seals for high-speed commercial vehicle and industrial diesel engines

The crankshaft seals in diesel engines used in lorries and stationary industrial applications are subjected to high loading factors. A previous article considered the vibration conditions in the engine [1] that influence the functioning of a seal. Mechanical, thermal and chemical factors also influence the design and choice of material for the seals. The seal technology discussed here is based on developments by Freudenberg Dichtungs- und Schwingungstechnik, Weinheim.

An investigation of crankshaft oscillations for cylinder health diagnostics

The vibrational characteristics of an internal combustion engine crankshaft are investigated from a cylinder health diagnostics point of view. Experimental results from a six-cylinder industrial diesel engine are presented to demonstrate the effects of cylinder imbalance on the individual harmonic components of the engine speed signal. A crank-angle domain numerical model of the crankshaft dynamics for a six-cylinder industrial diesel engine is also adopted to establish the effects of continuous low-power production in individual cylinders of a multi-cylinder engine. Outline of a diagnostics algorithm that makes use of the properties of crankshaft vibration behaviour is provided. In particular, crank-angle domain notch filters are employed to extact the harmonic components of engine speed. The outlined method can be implemented for individual cylinder health diagnostics across a family of multi-cylinder engines and can be formulated to handle changes in crankshaft characteristics due to replacement of mechanical components and/or wear.

A Fuzzy Diagnosis Module for Oil Analysis in Industrial Diesel Engines

This paper presents the basic characteristics of a prototype fuzzy expert system being developed in order to improve the performance of a binary-logic based software on the particular application of oil analysis of Diesel engines (for industrial and transport fleet use). The system allows for reasoning under absent or imprecise measurements, providing with an interval-valued diagnostic of the suspected severity of a particular fault. A set of so-called metarules complements the basic fault dictionary for fine tuning, allowing extra functionality such as linear transformations of membership prior to logic operations, discarding previous conclusions in some circumstances and introducing the possibility of detecting contradiction between different diagnostic alternatives for the same fault.

The influence of the fuel inlet temperature on diesel engine performance

The fuel inlet temperature has a significant influence on the performance levels of internal combustion engines, and this is particularly true for diesel engines. As a result, many passenger car manufacturers take this into account and incorporate a fuel temperature control system into their high-performance, latest-generation diesels. This paper describes a test project at Perkins for industrial diesel engines used in off-highway applications.

Design of An IC Engine Torque Estimator Using Unknown Input Observer

The torque produced by each combustion in an engine is one of the most important indices tied to internal combustion engine performance. In this paper, an approach is investigated to estimate engine torque. Instead of employing expensive and delicate combustion pressure sensors to directly measure indicated pressure in each cylinder, unknown input observers are exploited to estimate cylinder indicated torque using one or more low-cost measurements of crankshaft angular position. Necessary and sufficient conditions for the existence of such torque estimators for multi-cylinder engines are presented in the paper; these include the number of angular position sensors required and their suggested placement. Model reduction issues and the number of measurements required to obtain an acceptable estimate are also considered. The approach is applied to a six-cylinder industrial diesel engine.

The Use of Palm Oil as Diesel Fuel Substitute

The high cost of energy supplies as well as the concern over the availability of oil have brought much pressure on many countries to search for renewable energy sources, especially after the oil crisis in 1973. Vegetable oil fuels such as palm oil fuel provide one of the alternative forms of energy that are currently being studied, particularly as a diesel fuel substitute. The purpose of this note is to review the potential of palm oil as an alternative fuel in automotive and industrial diesel engines with respect to its performance and tribological, environmental, economic and social implications.

A Study on a Technique of the Measurement of Flame Temperature and Soot Using the Two-color Method in Diesel Engines

The instantaneous flame temperature and soot formation and oxidation in a D.I. diesel engine are measured using a two-color method. The proposed method based on the continuous spectral radiation from the soot particles in the flame is applicable to industrial diesel engines without major modifications of their main characteristics. Measurements are performed at one location inside the combustion chamber of a D.I. diesel engine. Effects of different engine speeds and loads on flame temperature and KL factor which is an index of soot concentration were examined. Little temperature change were observed with increasing rpm, while increased with loads. The higher the flame temperature is, the lower the KL factor is.

Gas Leakage from Piston-Ring of Small Out-put Diesel Engine

A small out-put industrial diesel engine was used and the conditions of its piston-rings were changed, for the study of phenomena on the piston-ring leakage. And the following conclusions were obtained mainly : (1) Leakage occurs at three passages which are the clearance spaces at the lower, outer side and gap of the ring. And the rates of leakage through each passage are nearly equal when these passages are of the similiar shape and size. (2) Angle and step joint cannot reduce the increase of the leakage as same as straight joint when the gap is enlarged. (3) When rings of the good and bad tightness are used together, the good ring only makes the gas-tight. (4) the greater part of the gas that leakes out is air, and it is believed that the harmfully incomplete combustion products are caused by combustion of the oils on the gas passages. (5) For reducing the specific fuel consumption, a smaller number of rings of good-tightness must be used.