Unit Injector Research Articles

Hybrid Solid State Fluidic Technique in Engine Fuel Injection Systems

This paper describes a multi-point fuel injection system utilizing fiuidic devices as fuel injector stages for spark ignition engines. The novel fuel injector unit consists of no-moving-part fluidic devices controlled by a solenoid valve interface and unique air/fuel mixing nozzles for good fuel atomization. The results of laboratory tests show that the fluidic device stage has a fast dynamic response and its on/off switching delay to the control flow signal is within 1 ms. A balanced fuel distribution at the four fluidic injector stages (for a four-cylinder engine) and well-atomized air/fuel mixture at the mixing nozzles were obtained from this injection system. The engine tests show that this fuel injection system provides an extended lean limit of the air/fuel mixture, 7 per cent improvement in fuel economy and 10 per cent reduction in hydrocarbon (HC) emissions compared with a base-line carburetted fuelling system due to the improved fuel distribution and air/fuel mixing quality by the multi-point fluidic injection system.

The dynamics of the object potential during electron beam injection and the possibility to control it

This review of the rocket and satellite experiments on electron beam injection in the height range of the ionosphere-magnetosphere shows a variety of manifestations of the positive charge potential on the body of the injector unit or in the space charge zone. The possibilities of compensation are considered on the basis of theoretical models taking into account the beam-plasma collective interactions. The examples of numerical modeling of the charge-discharge dynamics are provided for the APEX conditions. It is shown that changing the pulse form and rise rate (dI/dt) one can change the structure of the space charge zone i.e. try to create the strong disturbance or resonance conditions in the time interval of πω p≤ t ≤ t ion. From these positions, we consider the APEX facilities used to control the inflow current, the spectrum of energetic particles, the high-frequency oscillations and the spatial distribution of optical emissions in the injector vicinity with high time resolution.

Full-scale prototype of the continuous pellet injector for ITER

Abstract A full-scale prototype of the continuous pellet injector with parameters adequate to the requirements of ITER (pellet size, 6 mm; pellet velocity, 1.2–2.0 km s−1; injection rate, up to 6 s−1) is described. The principal parts of the injector are: the extrusion unit where fuel condenses and solidifies and which provides the extrusion; the rotor transporting unit, cooled by the helium flow; and the injector unit consisting of six channel light gas accelerator. A special attention is paid to the injectors safety and reliability.

Beam-energy control during a beam pulse in a neutral beam injection system

Capability of beam-energy control during a beam pulse has been demonstrated in the JT-60 neutral beam injection system. In addition to the acceleration voltage, the acceleration current and magnetic field separating residual ion beams were simultaneously varied. A preprogram control was adopted to cope with the relatively long time constant of the magnetic field due to the eddy current induced in the magnet core. The overall time constant is about 0.4 s. Beam-energy control was first tested in the prototype injector unit for JT-60 and then applied in JT-60 heating experiments. By advancing the idea demonstrated here, it is possible to design future neutral beam systems with real-time beam-energy control that follows target plasma evolutions.

Bronze Birch Borer Larval Control Using Systemic Insecticides in Ohio, 1989

Abstract A mixed stand of 3.5-5.0 m tall birches planted in 1983 were evaluated in Aug 88 for BBB. Nine paper birches with old BBB exit holes, nine paper birches with gouting but no exit holes, 18 European birches with exit holes and 12 European birches with gouting only were selected for treatments. Each tree category was divided into blocks of 3 trees (=16 total replicates). On the date of application, 26 Aug 88, the soil moisture was low due to a drought. Normal rainfall returned for Sep and Oct. Mauget Inject-A-Cide B 1.0 ml injector units with inch mini-microfeeder tubes (normal feeder tubes are inch) were used at rates of one tube/tree with breast diameter height (BDH) less than 8.0 cm and 2 tubes/tree with BDH ≥ 8.0 cm. The feeder tubes were attached at the root flare zone and the units remained on the trees until empty. Cygon 4 E was applied by mixing 150 ml in 1.0 gal of water and pouring around the tree base within a 0.3 m radius. Untreated checks received 1.0 gal of water. During the wk of 29 May 89 a 1.0 m long section of each tree was marked with a waterproof pen about 1.5 to 2.0 m above ground level. All existing BBB exit holes were marked. All trees were examined on 9 Aug 89 and the number of new exit holes/1.0 m segment were recorded.

Development of H− and D− ion sources for plasma heating

The large size of future, and possibly present day, tokamaks requires high neutral atom beam energies for current drive and heating. These injectors must also have a high electrical efficiency and this can be achieved using negative ion sources to create the beam. These large tokamaks, such as ITER or NET require a neutral beam power of around 50–100 MW at beam energy of 1 MeV of D0. This power is achieved by operating several sources in parallel, each one of which would extract a 28-A beam of D− ions of which 57% are converted to D0 in a gas cell neutralizer and can be transmitted to the torus. The injector for one port consists of four units, each of which is a fully independent unit. This article describes the details of the injector unit which is based on volume plasma sources of D− ions.

The Determination of Diesel Engine Friction Characteristics by Electronic Cylinder Disablement

The use of electronically controlled unit injectors on a high-speed direct injection diesel engine has allowed the development of a new technique for measuring motoring losses. The digital engine controller is programmed to skip successive numbers of injections in a specific circulating sequence, while dynamometer load is adjusted to maintain the desired speed. The linearity between required brake torque and the proportion of disabled to normal injection cycles permits extrapolation of results to find the negative load that would be required to motor the engine at that speed. The method appears to yield more reliable results than traditional approaches, and gives hot motoring values of mean effective torque without the need for external heating or a motoring facility. The equipment and method involved are described, and readings obtained for the whole speed range are presented. These are correlated with losses estimated from pressure measurements, and compared with friction characteristics produced by alternative techniques.

Coal–Water Slurry Operation in an EMD Diesel Engine

The U.S. Department of Energy, Morgantown Energy Technology Center has assumed a leadership role in the development of coal-burning diesel engines. The motivation for this work is obvious when one considers the magnitude of the domestic reserves of coal and the widespread use of diesel engines. The work reported in this paper represents the preliminary engine experiments leading to the development of a coal-burning, medium-speed diesel engine. The basis of this development effort is a two-stroke, 900 rpm, 216-mm (8.5-in.) bore engine manufactured by Electro-Motive Division of General Motors Corporation. The engine, in a minimally modified form, has been operated for several hours on a slurry of 50 percent (by mass) coal in water. Engine operation was achieved in this configuration using a pilot injection of diesel fuel to ignite the main charge of slurry. A standard unit injector, slightly modified by increasing diametric clearances in the injector pump and nozzle tip, was used to inject the slurry. Under the engine operating conditions evaluated, the combustion efficiency of the coal and the NOx emissions were lower than, and the particulate emissions were higher than, corresponding diesel fuel results. These initial results, achieved without optimizing the system on the coal slurry, demonstrate the potential for utilizing coal slurry fuels.

The JT-60 neutral beam injection system

The JT-60 neutral beam injection system has been designed to inject a neutral hydrogen beam power of 20 MW at energies of 75–100 keV for 10 s. The system consists of 14 beamline units, 14 power supply units for the ion sources, a liquid helium and liquid nitrogen cryogenic system for the beamline cryopumps, a demineralized cooling system for heat dump materials, an auxiliary pumping system, and a computer aided control system. Each beamline unit is made with essentially the same geometry as that of the prototype injector unit, which was constructed in 1981 and tested from 1981 to 1983 to confirm unit performance. Each power supply unit provides a voltage regulated output of 100 kV, 90 A. The helium refrigerator has a cooling capacity of 3000 W at 3.6 K. Beam energy and the pulse timing of each unit can be set up independently. Since April 1984, each beamline unit has been tested and conditioned up to 75 keV, 70 A, 10 s at the prototype injector facility. Beamlines have been installed on JT-60 and completion of the total system is scheduled for July 1986.

Crack and Crevice Application of Chlorpyrifos Against the German Cockroach, 1984

Abstract 0.50% chlorpyrifos was applied using crack and crevice (C&C) techniques with 3 different pieces of application equipment. Pieces evaluated were B&G compressed air sprayer equipped with C&C application tip, the B&G Injector Unit, model 124s, and the Whitmire PT System III. The latter 2 pieces were aerosol treatments. Multi-family, public housing units located in Indianapolis, IN served as the test sites.

Performance of the Prototype JT-60 Injector Unit in the Presence of a Simulated Stray Magnetic Field

Influence of the magnetic field, which is produced around the JT-60 tokamak, on the performance of the neutral beam injector was experimentally studied using the stray field simulating coils instal...

Measurement of neutral beam species ratio by solid-state detector

Energy spectra of neutral hydrogen beams produced at the prototype JT-60 neutral beam injector unit were measured by the solid-state detector which was developed for a neutral particle analyzer for fusion devices. The ion beam species ratio estimated from the energy spectra agreed well with that measured by the Doppler-shift spectrometer.

Hydrogen gas re-emission from beam target bombarded by intense neutral hydrogen beam of 75–100 keV, 1.4 MW at the prototype JT-60 injector

A beam target made of oxygen-free copper with 0.2% silver added was bombarded by a intense neutral hydrogen beam of 75–100 keV, 1.4 MW for 10 s at the prototype injector unit for JT-60 neutral beam injection. Hydrogen gas which was re-emitted from the beam target at the time constant of about 1 s was evacuated by a cryopump with a pumping speed of 960 m3/s. We compared the re-emitted hydrogen gas flow rate from the beam target with the number of particles in the hydrogen beam and concluded that the hydrogen gas re-emission coefficient is almost 1.

Effects of treating western spruce budworm populations on grand fir and Douglas-Fir with acephate, carbofuran, dimethoate, oxydemeton-methyl, and methamidophos

Systemic implantation cartridges containing liquid formulations of acephate or methamidophos provided 98% and 90% population reduction of western spruce budworm larvae on grand fir. Acephate residue levels in midcrown foliage reached laboratory determined LC 90 values for western spruce budworm larvae within 5 days after treatment. Medicap cartridges containing powdered formulations of carbofuran or dimethoate and Mauget injector units containing a liquid formulation of oxydemeton-methyl provided inadequate population reduction: whereas, Medicaps containing a powdered formulation of acephate provided 93% population reduction. Acephate residue levels in midcrown foliage were sufficient to cause mortality of western spruce budworm larvae by 20 days after treatment.

Geometrical efficiency of the prototype neutral beam injector unit for JT-60

The geometrical efficiency of the prototype neutral beam injector unit for the JT-60 was measured experimentally and was compared with numerical estimates. The measurements agreed well with the calculations in the wide range of perveance by taking into account the distortion of the beamlet intensity distribution function from a Gaussian distribution. Overdense operation of the ion source was preferable in that the high geometrical efficiency could be obtained at high perveance values.

Production of 75-keV, 70-A, 10-s ion beams

High-power long pulse ion sources were fabricated and tested at a prototype injector unit for JT-60. Ion beams of 70 A at an energy of 75 keV were extracted repeatedly for up to 10 s. The heat loadings to each grid were within our design values and each grid turned out to be thermally stable during 10 s pulse. The neutral beam power deposited to the beam target was over 1.43 MW, which corresponds to the design value of the JT-60 neutral beam injector. The e-folding half-width beam divergence angle was about 1.0° at optimum beam current and a proton ratio of about 80% was obtained. It was also confirmed that other beam line components, such as the ion beam dump and the cryopump, were sufficiently reliable.

Studies on a Unit Injector for Cars with High-Speed Engines

The development of modern diesel engines is moving towards increased power per unit of displacement, lower engine weight, wider speed range, better fuel economy and lower noise and pollution levels. Due to these trends Friedmann and Maier have developed a new injection system, the unit injector, (Figs 1 and 2). This paper deals with the development of the unit injector, its special features and its advantages and disadvantages in comparison with conventional in-line pumps.

Studies on a Unit Injector for Cars with High-Speed Engines

Studies on a Unit Injector for Cars with High-Speed Engines

Effect of injector unit design on the particle size of atomized powder

Effect of injector unit design on the particle size of atomized powder

Survey of liquid metal magnetohydrodynamic energy conversion cycles

The maximum predicted efficiencies for the four basic LM-MHD cycles and all modifications included in this review are shown in Table 3. The maximum cycle temperature ranged from 1120 to 1500°K, with a mean value of 1370°K; the minimum cycle temperature ranged from 700 to 1090°K, with a mean value of 920°K; and the generator was assumed to have an efficiency of 70 per cent. The following observations and comments are made: 1. (1) For all cycles two-component mixtures yield higher efficiencies than single-component fluids by approximately a factor of two. The only exception is the high value reported [35] for a potassium emulsion cycle (14 per cent). Since it was difficult to evaluate the conditions under which this value was obtained, this efficiency should be regarded as perhaps a somewhat optimistic estimate. 2. (2) The most efficient one-component material, regardless of cycle, is cesium. Although the table indicates that for some cycles, potassium-lithium is a more efficient two-component material than cesium-lithium, the greater solubility of potassium in lithium may render that combination less useful than cesium-lithium. 3. (3) The maximum efficiencies of the two different basic fog flow cycles are essentially equal; 3–4 per cent for one component, 6–8 per cent for two-component cycles. 4. (4) The predicted efficiencies of both the separator and injector-condenser cycles exhibited significant increases upon modification. Efficiencies in the 10–20 per cent range are typical for these modified cycles. However the added complexity and potentially increased frictional losses must be considered. 5. (5) The most developed cycles are the injector-condenser and separator cycles. However, both of these fog flow cycles tend to have lower efficiencies than the two-phase cycles. This is due to the larger losses in the separator and injector units. For this reason it would appear that modifications of the emulsion and slug flow cycles should be investigated. 6. (6) The highest predicted cycle efficiency, 30 per cent, is for a basic two-component slug flow system using potassium and lithium.