Showing papers on "Diesel engine published in 1979"

Current status of droplet and liquid combustion

Abstract: The present understanding of spray combustion in rocket engine, gas turbine, Diesel engine and industrial furnace applications is reviewed. In some cases, spray combustion can be modeled by ignoring the details of spray evaporation and treating the system as a gaseous diffusion flame; however, in many circumstances, this simplification is not adequate and turbulent two-phase flow must be considered. The behavior of individual droplets is a necessary component of two-phase models and recent work on transient droplet evaporation, ignition and combustion is considered, along with a discusssion of important simplifying assumptions involved with modeling these processes. Methods of modeling spray evaporation and combustion processes are also discussed including: one-dimensional models for rocket engine and prevaporized combustion systems, lumped zone models (utilizing well-stirred reactor and plug flow regions) for gas turbine and furnace systems, locally homogeneous turbulent models, and two-phase models. The review highlights the need for improved injector characterization methods, more information of droplet transport characteristics in turbulent flow and continued development of more complete two-phase turbulent models.

Diesel engine exhaust particulate filter with intake throttling incineration control

Abstract: Diesel exhaust filter and incineration control systems are disclosed which provide intake throttling of the diesel engine as a primary means of raising exhaust temperature in the filter for the periodic burn-off of collected particulates. Various embodiments and supplemental means of increasing exhaust temperatures are also disclosed.

A Study on the Application of the Two–Color Method to the Measurement of Flame Temperature and Soot Concentration in Diesel Engines

Abstract: Results are presented of optical measurement of the flame temperature and KL factor (soot concentration) in a direct injection diesel engine using the two-color method. In the latter stages of combustion, the infrared two-color method gave a lower value than the visible two-color method, the difference being enhanced with crank angle advancement. The KL factor value obtained by the visible method was about half that of the infrared method. These differences were caused by the alpha index (wavelength dependency of flame emissivity) change in the infrared region during the combustion period; the effect at both wave lengths of uneven distributions of temperature and soot concentration along the optical path; and the effect of the reflection of the opposite wall on the infrared method. The optical characteristics and other instrumentation problems of the two-color method at both wavelengths are also discussed.

Installation of a diesel-organic rankine compound engine in a class 8 truck for a single-vehicle test

Abstract: A class 8 truck has been equipped with a diesel-organic Rankine compound engine in preparation for a 1-year test program. The compound engine consists of an organic Rankine bottoming cycle system directly coupled to a Mack diesel engine from which it recovers the waste heat in the exhaust gases. The components of the bottoming cycle system are described, and their installations in three pre-assembled modules -- a power conversion package, a vapor generator, and a cooling system -- are discussed. Plans for the 1-year test program, including baseline performance tests on the compound engine, chassis dynamometer tests, noise tests, and over-the-road fuel economy measurements, are also outlined.

Nitrogen Dioxide in Engine Exhaust

Abstract: Nitrogen dioxide emissions from diesel and gasoline internal combustion engines have been measured over a range of speed, load and AFR conditions Measured NO2 levels are very much higher than expected thermodynamically, with as much as 30% of the NOx emission from a diesel engine at 15% load in the form of NO2 Stainless steel surfaces, platinum and copper chromite catalysts, when in the temperature range 400 - 500 degrees C have been shown to oxidise NO to NO2 provided the CO concentration in the exhaust gas is below 01% Analytical techniques and methods of removing NO2 have been considered

A study on the time and space resolved measurement of flame temperature and soot concentration in a d.i. (direct injection) diesel engine by the two-color method

Abstract: The two-color method for measuring the visible wavelength radiation from soot particles in flames was closely studied as a possible technique for measuring flame temperature and soot concentration in diesel engines. The accuracy of the temperature calibration of the measuring equipment was assured by a newly developed, high-temperature black-body furnace and a standard tungsten lamp. The emissivity of diesel flames, the most important value in this method, was investigated by the spectroscopic analysis of soot sampled from a diesel flame and by comparative measurements between the two-color method and the emission-absorption method. When the two-color method was applied to a direct injection diesel engine, the time and space resolved values of temperature and soot concentration were obtained for the first time.

Diesel fuel containing manganese tricarbonyl and oxygenated compounds

Abstract: The amount of soot and invisible particulates emitted with the exhaust of engines run on diesel fuel is reduced by incorporating therein an additive consisting of a mixture of an oxygenated compound and an alkyl cyclopentadienyl manganese tricarbonyl. Also disclosed is a method of operating a diesel engine using the fuel of the invention.

Internal combustion diesel engine

Abstract: An internal combustion diesel engine has a fuel injection means for injecting fuel directly into one or more combustion chambers. Each combustion chamber has a first air-intake duct for supplying air to the combustion chamber, which first duct is designed as a swirl duct. A second air-intake is associated with each combustion chamber and is connected in parallel with the first duct for supplying an increasing quantity of substantially swirl-free air to the combustion chamber in response to increasing engine speed.

Water injection system for diesel engine

Abstract: An electric pump delivers water from an reservoir to a nozzle located in the air intake manifold of a diesel engine. The pumping capacity of the pump is adjustable by varying the resistance of a variable resistor in series with the pump so that the system can be used with various engines requiring different amounts of water. Several safety switches are provided to prevent water from being pumped unless the engine is running at a predetermined speed, a predetermined oil pressure is reached and the throttle is depressed. An indicator light indicates when the water reservoir is empty and needs refilling.

Flowfield Modeling in Practical Combustors: A Review

Abstract: A. Some Engineering Combustion Processes I combustion system design and development today, efforts are being expended on producing efficient and clean combustion in a variety of practical situations. Here are some examples: 1) The gasoline engine. Here the combustion system must be free from "knock," give certain ignition by spark, reduce heat transfer, and burn fuel completely under all conditions. 2) The diesel engine. High compression must provide smooth ignition, use all available oxygen, reduce heat transfer, reduce pumping power, and emit little smoke. 3) The industrial furnace. Flame control is especially important in providing specified distributions of radiant and convective heat transfer, complete combustion, freedom from noise and oscillation, and insensitivity to fuel changes. 4) The gas turbine. This is a high-intensity combustion engine which must burn fuel completely, cause little pressure drop, produce gases of nearly uniform temperature, occupy small volume, and maintain stable combustion over a wide range of operating conditions (pressure and air-fuel ratio, for example). The combustion designer has a formidable problem in aerothermochemistry, and the task is to provide a route which leads to the accomplishment of design objectives more quickly and less expensively than current practice permits.

Effect of partial suppression of heat loss to coolant on the high output diesel engine cycle

Abstract: The paper describes the results of a detailed cycle analysis applied to a high output 6 cylinder truck diesel engine: 1) conventional form; 2) with a uniformly distributed layer of silicon nitride giving approximately isothermal wall conditions; and 3) with adiabatic wall conditions. For case (1) the benefits are largely limited to increased exhaust enthalpy, suggesting the desirability of turbocompounding. Case (2) gives marked improvement in cycle efficiency as well as raised exhaust enthalpy. Paper number 790823.

Fuel control system for a dual-fueled power unit

Abstract: A turbo-charged, inter-cooled governed speed diesel engine directly coupled to an alternator for electrical generation is adapted for dual-fuel operation and mounted on a trailer which also supports the engine's fuel sources including diesel fuel in a conventional tank. The second fuel is producer gas generated in a down draft continuously operating producer of the moving-packed-bed vertical flow reactor type with co-current gas flow. Solid waste such as crop residues, e.g., corn cobs, is used as fuel stock for the producer and is conveyed automatically to the producer from a bin on the trailer. Before delivery to the air intake of the diesel engine the producer gas is conditioned by passing it through a cyclone and filter to remove solid particulate matter and a cooler-condenser for cooling the gas and condensing out tars. The diesel governor and fuel pump assembly is modified only by the application of a fuel rack stop for maintaining a pilot flow of diesel fuel and the engine control system is such that the response of the diesel injection system to changes in engine load is normal in general; however, automatic controls are provided for monitoring diesel pump fuel rack position and engine load so that after engine loading is increased a throttle valve in the gas supply to the engine is progressively and relatively slowly opened tending to increase engine speed so that the diesel injection rate is conventionally cut back correspondingly until an equilibrium condition is reached in which engine fuel demand in excess of the pilot minimum diesel fuel flow required to maintain combustion is provided by producer gas. The response of the system to a decrease of engine loading when the engine is operating at minimum diesel fuel flow (that is with the fuel rack stop effective) is to reduce fuel supply rapidly and appropriately by partially closing the gas throttle valve. Automatic safety shutdown provisions include, in at least one shutdown mode, delayed shutting off diesel fuel flow following producer gas shutoff so that the engine and exhaust system are purged of producer gas so as to reduce explosion hazards.

Fuel system for diesel engines

Abstract: Fuel for a diesel engine is fed to the engine through a small float tank provided with a fuel heater. A cooling unit is employed to cool overheated fuel recycled from the engine. A temperature controlled valve is utilized to divert recycled fuel from the cooling unit through the float tank and back to the engine if the recycled fuel is sufficiently cool. The fuel heater, cooling unit and valve are adapted to optimize fuel temperature based on engine performance design. Water, propane, LPG, etc. also may be injected into the engine along with the diesel fuel to improve the combustion process and fuel economies.

Fuels and their use

Abstract: A fuel especially a fuel for an automobile, internal combustion engine or a diesel engine comprising a hydrocarbon water and emulsifier wherein the emulsifier is a non-ionic emulsifier and comprises the addition product of ethylene oxide or propylene oxide and a carboxylic acid amide with 9 to 21 carbon atoms.

Temperature Distribution of Piston Rings and Piston in High Speed Diesel Engine

Abstract: Temperature distribution and thermal correlation of piston rings and piston in high speed diesel engines under actual operating conditions, in spite of their importance, have not been clarified due to the difficulties involved in the measurement. Authors overcame the difficulties and the temperatures were measured directly and precisely by means of thermocouples. As the result, concerning the heat flow pattern and the flow rate, interesting differences among the top, the second and the oil rings, and also between the plain and the taper faced ring were revealed. In addition, the amount of heat transferred to the piston, and the parcentage of each heat released from the piston to other parts were determined.

Diagnosis of engine power and compression balance

Abstract: This disclosure relates to a system for analyzing the performance of a reciprocating piston, internal combustion engine such as a diesel engine. Sensors are connected to the engine, which respond to various operating parameters, and signals representing the parameters are transmitted to computer processing equipment. A speed sensor responds to the movement of an engine part such as the teeth of the engine fly-wheel ring gear, and the processor calculates a function representing the change in the instantaneous engine kinetic energy. The kinetic energy change data are accumulated during an engine acceleration run and again during a deceleration run. The signals from an engine cycle event sensor are processed to indicate the firing intervals of the cylinders and thereby to correlate the engine acceleration and deceleration data. The changes in kinetic energy during the cylinder firing intervals are measured during engine acceleration, and the kinetic energy changes are again measured during deceleration, the two sets of measurements being at substantially the same engine speed. For each cylinder, the measurement on deceleration is subtracted from the related measurement on acceleration, to obtain the net work produced by each cylinder. A similar procedure may be followed to obtain the work done over segments of each firing interval, to thereby check the compression balance of the cylinders.

The Use of a Thermogravimetric Analyser for the Investigation of Particulates and Hydrocarbons in Diesel Engine Exhaust

Abstract: The conditions necessary for obtaining samples of diesel particulates in Constant Volume Sampling (CVS) tunnels were investigated for simultaneous analysis of gaseous hydrocarbons present in equilibrium with particulate borne hydrocarbons. Thermogravimetric analysis was developed for separating particulates components in a simple way. A reliable instrument was interfaced with a heated flame ionization detector (HFID) which gave additional or corroborative information. A system was evolved for total diesel hydrocarbon analysis, using thermogravimetry for hydrocarbons trapped on the particulate filter, and HFID for those passing through the filter. When the results were compared with total hydrocarbon analysis by the Federal Test Procedure, a small gain in hydrocarbon recovery was shown with an increase in overall information for the new system. Thermogravimetry was found to be a useful tool for diesel engine development, particularly if interfaced with a heated flame ionization analyser. Thermogravimetry offers a new way of reliably separating and describing the various groups of hydrocarbons in diesel exhaust which can be used by emissions laboratory staff. The CVS tunnel was shown to have good mixing and very low losses. Results confirm the validity of the diesel hydrocarbon analysis procedure by heated flame ionization detector (decreed by the Environmental Protection Agency), as long as the whole system is maintained at the correct temperature (190 degrees C).

Method for reducing particulates discharged by combustion means

Abstract: The method and apparatus for controlling particulate emissions from a combustion apparatus, as a diesel engine. Diesel engine exhaust particles are electrically charged during the formation of the particles in the engine combustion chambers. A particle collector is used to collect the electrically charged particles on collecting structures connected to a high voltage power supply and ground. The collecting structures of the particle collector can be a plurality of parallel metal plates, spaced cylindrical rods, or concentrically located cylindrical members. A fibrous matrix can be located adjacent the particle collecting structure to collect the charged particles as they move through the matrix. In one embodiment, the collected particles separate from the collecting structures and return to the engine intake. In another embodiment, a removable collecting cartridge has electrically conductive plates for collecting the charged particles. The entire cartridge is removed for cleaning or replacement. The hot exhaust gas from the engine can be used to oxidize the collected particles. The collected particles that are not oxidized can be separated from the collecting structures and re-entrained into the gas. The re-entrained particles are larger than the particles formed in the combustion apparatus. The large particles can be removed by a downstream particle collection device.

System for heating fuel oil

Abstract: A mechanism (10) for heating diesel fuel in a diesel engine vehicle is disclosed. The mechanism (10) includes a heat exchange conduit (18), a portion of which is adapted to be held in the interior of a fuel tank (12) of a diesel engine (16). An inlet conduit (42) connects an inlet end (30) of the heat exchange conduit (18) to a water manifold (44) of the diesel engine (16). An outlet conduit (46) connects an outlet end (32) of the heat exchange conduit (18) to the engine block (48) of the diesel engine (16). In this manner, coolant liquid from the diesel engine (16) is passed through the heat exchange conduit (18) to heat diesel fuel contained in the fuel tank (12).

Diesel engine having a subchamber

Abstract: A Diesel engine having a subchamber in the cylinder head in which the exhaust gas recirculating (EGR) passageway is coupled to the subchamber with a valve means controlled in synchronism with the rotation of the engine so that only the minimum necessary amount of EGR gas is present exclusively in the subchamber at the beginning stage of engine combustion in order to decrease the generation of NOx products while maintaining good combustion.