Nozzle (from the English force-pump - pressure pump) - a device with one or more calibrated holes [1] for spraying (atomizing) any liquids (less often powder) under pressure, mainly of liquid fuel, when it is supplied to steam furnaces boilers, cylinders of internal combustion engines [2] in order to achieve a more perfect combustion [3] . Injectors provide uniform fuel supply and more complete combustion [1] . It is controlled by a solenoid valve or mechanically.
It is used to spray fuel ( black oil , diesel fuel , gasoline ), for example in fuel injection systems , they are sprayed due to high fuel pressure (several atmospheres for supplying gasoline or gas with distributed injection into the manifold and hundreds to thousands of atmospheres for direct injection of gasoline or diesel fuel) [4] .
In nozzles for washing cars , a pressure of 10β20 MPa (100β200 bar ) is used [5] .
History
The first workable nozzle was proposed by Alexander Ilyich Shpakovsky in 1864. Then the nozzle, created in 1880 by engineer Vladimir Grigoryevich Shukhov , played a large role [6] . Shukhov nozzle due to manufacturability, simplicity of design and ease of manufacture has become widespread [7] .
Application
Use of nozzles [8] [9] [10] :
- liquid fuel combustion [1]
- humidification in ventilation devices [1]
- dust control
- coating materials
- gas cleaning and cooling
- fire protection
- cleaning and washing
- leak test
Types of nozzles
Types of nozzles [11] [1] :
- mechanical;
- electromagnetic
- piezoelectric
- hydraulic
According to the principle of spraying the liquid, the nozzles are divided into mechanical (liquid with high speed flows into the gaseous medium), pneumatic or steam (liquid with low speed moves into the moving gas stream), as well as a combined type, the so-called air-mechanical or steam-mechanical and preliminary gasification [7] / Distinguish such nozzles: jet, vortex and centrifugal [1] .
Principle of action and scope
Mechanical nozzles are conventionally divided into direct action and centrifugal. Direct-acting nozzles are mainly used in internal combustion engines. Fuel is supplied to them with significantly higher pressure (sometimes over 100 MPa) than in centrifugal ones. In centrifugal nozzles, fuel under pressure (mainly 0.6-6 MPa) is twisted in the channels or in the vortex chamber and ejected through the nozzle. Centrifugal type nozzles differ in design, there are nozzles with reverse drain of liquid fuel, with an adjustable area of ββthe twisting holes, multi-nozzle, rotary and others. For better dispersion, high fluid velocities are usually created, which leads to a decrease in the diameter of the nozzle outlet openings and the tangential openings of the vortex chambers; therefore, mechanical nozzles are demanding for fuel cleanliness [7] .
In pneumatic (steam) nozzles, dispersion is mainly carried out by a gas stream. They have more bulky communications, a complex economy, but are less demanding on part processing and fuel cleanliness [7] .
Pneumatic nozzles of a high pressure are direct-jet and centrifugal. The gas pressure is usually 0.3-0.7 MPa, sometimes more. Often used steam pressure of 0.3-1.2 MPa, sometimes up to 2.5 MPa. Among the direct-jet nozzles, the so-called ejection nozzles are widely used, which are widely used in energy and industrial furnaces. Centrifugal nozzles are used in the combustion chambers of gas turbines [7] .
Design
Nozzles have a variety of designs. The design of the nozzles depends on the purpose for which they are intended [1] .
The most important nozzle element is the nozzle . As a rule, the nozzle consists of one, less often two channels. The first is the sprayed liquid, the second liquid, steam , gas , which serves to spray the first liquid. A clean, high-quality nozzle gives a cone-shaped spray, and the torch is smooth and continuous [12] .
Key Features
Key Features [13] [14] [15] :
- injection start pressure (adjustable for mechanical injectors)
- dynamic range of operation and minimum cyclic fuel supply
- nozzle opening and closing time (delay)
- spray cone angle and range of the fuel torch
- particle size and fuel distribution in the flare
Diesel Injector
The device nozzle of the car " KrAZ-255 " [16] :
- Body.
- Spray gun nut.
- Spray.
- Needle.
- Sealing washers.
- Pin.
- Stock.
- Plate.
- Spring.
- Adjusting screw.
- Nut.
- Lock-nut.
- Cap.
- Fitting
- Sleeve.
- Filter.
- Seal fitting.
The principle of operation of the nozzle of the KrAZ-255 car:
Fuel flows under pressure into an annular chamber formed between the atomizer body and the needle. Due to the fuel pressure, the needle rises and compresses the spring, while the nozzles of the atomizer open, and through them the fuel is injected into the cylinder. When the pressure decreases, the needle lowers due to the spring and its own weight, closes the nozzles, stopping fuel injection (its pressure depends on the compression of the spring with the adjusting screw).
See also
Wobbe number
Notes
- β 1 2 3 4 5 6 7 Injector // Big Polytechnical Encyclopedia: more than 7000 dictionary entries / [ed. Ryazantsev V. D.]. - M .: World and Education, 2011 .-- 700 p. - ISBN 978-5-94666-621-3 .
- β nozzle // Large explanatory dictionary of the Russian language / Russian Academy of Sciences, Institute of Linguistic Studies; [ch. ed. S.A. Kuznetsov]. - SPb. : Norint, 1998.
- β nozzle // Explanatory dictionary of the Russian language : in 4 volumes / chap. ed. B. M. Volin , D. N. Ushakov (t. 2-4); comp. G. O. Vinokur , B. A. Larin , S. I. Ozhegov , B. V. Tomashevsky , D. N. Ushakov ; under the editorship of D.N. Ushakova . - M .: State Publishing House of Foreign and National Dictionaries, 1940. - T. 4: C - Foot and mouth disease. - Stb. 1105.
- β Injector of an internal combustion engine . www.auto-infosite.ru. Date of treatment December 8, 2017.
- β Nozzles for high pressure pressure washers . ChemProfi. Date of treatment December 8, 2017.
- β Spraying of liquids / V. A. Borodin, Yu. F. Dityakin, L. A. Klyachko, V. I. Yagodkin. - M .: Mechanical Engineering, 1967 .-- 263 p.
- β 1 2 3 4 5 Spraying liquid with nozzles / L. A. Vitman, B. D. Katsnelson, I. I. Paleev; Ed. S. S. Kutateladze. - M .: Gosenergoizdat, 1962. - S. 9-12. - 264 p.
- β Spraying Systems Co. Spraying Systems Co. Spray Systems for Refrigeration and Air Conditioning . www.sprayrus.ru. Date of treatment December 8, 2017.
- β Systems and methods for cooling the workpiece . steeltimes.ru. Date of treatment December 8, 2017.
- β Nozzles and spray systems Lechler . kraftlog.ru. Date of treatment December 8, 2017.
- β What is a nozzle and what are they? (Russian) . Date of treatment December 8, 2017.
- β Types and design of injectors of injection systems . avtodisel.ru. Date of treatment December 8, 2017.
- β Characteristics of nozzles of the Common Rail system - Denso . www.denso-am.ru. Date of treatment December 8, 2017.
- β How to choose a gas nozzle? Which gas nozzles are better to buy? | GBOshnik (Russian) (neopr.) ? . gboshnik.ru. Date of treatment December 8, 2017.
- β Ilya Serb - www.insar.me. Fuel nozzles: types, theory, cleaning . www.ej9.ru. Date of treatment December 8, 2017.
- β (auto-expert), Eugene . The device of the diesel engine nozzle (Russian) (February 4, 2016). Date of treatment December 8, 2017.