Behaviors of Spray Droplets with and without Flat Wall Impingement

In this article, the spray wall-impingement experiments were carried out under the common rail condition by image acquisition system to study the wall shape impact on the diesel spray impingement. The results showed that the scatter direction of impinged spray, shape of impinged spray can be changed by the wall shape significantly. With the increasing of injection pressure, spray splash volume relatively increases and atomization is enhanced when the spray impinges on a flat wall; the development of distance along the wall is nose-shape 90 degree > 135 degree.

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CHARACTERISTICS OF SPRAYS THROUGH A WALL IMPINGEMENT INJECTOR

Atomization and Sprays ◽

10.1615/atomizspr.v14.i4.40 ◽

2004 ◽

Vol 14 (4) ◽

pp. 375-395 ◽

Cited By ~ 10

Author(s):

Takao Inamura ◽

Terutoshi Tomoda

Keyword(s):

Wall Impingement

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EVALUATION OF PULSED LASER HOLOGRAMS OF SPRAY DROPLETS BY APPLYING DIGITAL IMAGE PROCESSING

Proceeding of International Heat Transfer Conference 9 ◽

10.1615/ihtc9.2840 ◽

1990 ◽

Cited By ~ 1

Author(s):

Anseimo Chavez ◽

Franz Mayinger

Keyword(s):

Image Processing ◽

Digital Image Processing ◽

Digital Image ◽

Pulsed Laser ◽

Spray Droplets

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Effect of pH and NH4NO3 as a Spray Additive on Penetration of NAA Through Isolated Tomato Fruit Cuticle

HortScience ◽

10.21273/hortsci.33.3.550a ◽

1998 ◽

Vol 33 (3) ◽

pp. 550a-550 ◽

Cited By ~ 1

Author(s):

Royal G. Fader ◽

Martin J. Bukovac

Keyword(s):

Direct Measurement ◽

Sodium Citrate ◽

Tomato Fruit ◽

Initial Slope ◽

Control Effect ◽

Solution Ph ◽

Ph Change ◽

Effect Of Ph ◽

Spray Droplets ◽

Partition Behavior

We have reported that NH4NO3 (AN, 8 mM, pH 4.2), applied as simulated spray droplets, enhanced penetration of 14C-NAA through isolated leaf and fruit cuticles. One explanation for this response is that AN depresses NAA (pKa= 4.2) dissociation, increasing the nondissociated moiety, which penetrates more readily than the anion (NAA'). Direct measurement of AN (concn. 0-800 mM) effect on NAA (215 μM) dissociation as indexed by change in solution pH revealed no significant effect, with a pH change from 4.19 to 4.05. This change is not sufficient to account for the observed enhancement. When 14C-NAA, buffered (20 mM sodium citrate) at pH 3.2, 4.2, 5.2, 6.2, was partitioned against chloroform, there was a marked increase in NAA partitioning into chloroform as pH was decreased. AN (8 mM) did not alter this partition behavior, also indicating no effect on NAA dissociation. However, in cuticle penetration studies, using a finite dose system with 14C-NAA buffered at pH 3.2, 4.2, 5.2, 6.2, and in the presence and absence of 8 mM AN, there was no marked or consistent pH or AN (-70 to + 232 % of no AN control) effect on penetration as indexed by initial slope (4-12 h) or penetration after 120 h. The possible effects of AN and buffer on penetration of 14C-NAA from the droplet deposit will be discussed.

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An Improved Rate of Heat Release Model for Modern High-Speed Diesel Engines

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.4036101 ◽

2017 ◽

Vol 139 (9) ◽

Cited By ~ 3

Author(s):

Peter G. Dowell ◽

Sam Akehurst ◽

Richard D. Burke

Keyword(s):

Heat Release ◽

Diesel Engines ◽

Engine Speed ◽

Fuel Injection ◽

Maximum Pressure ◽

Injection Model ◽

Wall Impingement ◽

Small Set ◽

Rate Of Heat Release ◽

Engine System

To meet the increasingly stringent emissions standards, diesel engines need to include more active technologies with their associated control systems. Hardware-in-the-loop (HiL) approaches are becoming popular where the engine system is represented as a real-time capable model to allow development of the controller hardware and software without the need for the real engine system. This paper focusses on the engine model required in such approaches. A number of semi-physical, zero-dimensional combustion modeling techniques are enhanced and combined into a complete model, these include—ignition delay, premixed and diffusion combustion and wall impingement. In addition, a fuel injection model was used to provide fuel injection rate from solenoid energizing signals. The model was parameterized using a small set of experimental data from an engine dynamometer test facility and validated against a complete data set covering the full engine speed and torque range. The model was shown to characterize the rate of heat release (RoHR) well over the engine speed and load range. Critically, the wall impingement model improved R2 value for maximum RoHR from 0.89 to 0.96. This was reflected in the model's ability to match both pilot and main combustion phasing, and peak heat release rates derived from measured data. The model predicted indicated mean effective pressure and maximum pressure with R2 values of 0.99 across the engine map. The worst prediction was for the angle of maximum pressure which had an R2 of 0.74. The results demonstrate the predictive ability of the model, with only a small set of empirical data for training—this is a key advantage over conventional methods. The fuel injection model yielded good results for predicted injection quantity (R2 = 0.99) and enabled the use of the RoHR model without the need for measured rate of injection.

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The toxicity of some insecticidal sprays to adult locusts

Bulletin of Entomological Research ◽

10.1017/s0007485300048343 ◽

1962 ◽

Vol 53 (3) ◽

pp. 597-608 ◽

Cited By ~ 3

Author(s):

R. D. MacCuaig

Keyword(s):

Schistocerca Gregaria ◽

Droplet Diameter ◽

Flight Activity ◽

Spray Application ◽

Single Drop ◽

Flying Insects ◽

Spray Droplets ◽

Tentative Explanation

The toxicities of sprays of some insecticides used against locusts have been determined. The LD50's of γ BHC, diazinon, and dieldrin to both flying and settled adults of Schistocerca gregaria (Forsk.) were between 0·9 and 1·5 times those of the same formulations when applied as a single drop to the abdomen. The toxicity of these insecticides was not affected by the size of the spray droplets when these ranged from about 60 to 250 µ in diameter. The toxicity of DNC, however, was always less by spray application than when applied by micro-drop syringe and was affected by the droplet diameter (droplets of 100 µ being 1·5 times as toxic as those of 200–230 µ) and by whether the locusts were sprayed in flight or when tethered on a card (those in flight being about 1·6 times as susceptible to 100 µ droplets as those at rest). A tentative explanation of this effect is given.The speed of action of the insecticides was compared and the effects of flight activity on susceptibility to the insecticides when sprayed over the flying insects was examined, but none could be detected by the technique used.

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