国产日韩亚洲大尺度高清,国产高潮流白浆喷水免费网站,97久久综合区小说区图片区,精品国产免费第一区二区三区

Member Login English Home 中文版 日本語(yǔ)版 BBS Blog
Navigation
Home Page
Tungsten's News
Tungsten's News,International
Tungsten's News,China
Powder Metallurgy Technology
News of Molybdenum
News of Refractory Metals
History of Tungsten
Sports & Tungsten
Military & Tungsten
Environment & Tungsten
Radiation Medical & Tungsten
Marketing of Tungsten
Tungsten Ore
Tungsten Oxides & Trioxides
Tungsten、Carbide Powder
Pure Tungsten
Tungsten Welding Electrodes
Tungsten Heavy Alloy
Tungsten Copper
Tungsten Jewelry
Ferro Tungsten
Tungsten Carbides
Tungsten Alloy Darts
Scrap Tungsten
Tungsten Alloy Bucking Bars
Non-ferrous metals
Molybdenum Related
Nickel Related
Cobalt Related
Vanadium Related
Titanium Related
Rare Earth
Technology of tungsten
Acknowledge of tungsten
Academic of tungsten
Research & Development
Patented Technology
Information Services
Information Offer
Advertising
Translation Services
Agent & Representative
Magazines & Books of tungsten
Tungsten for Combustion Chamber of Turbo Engines
Author:Felility    Source:Chinatungsten Online    Update Time:2010-1-14 9:18:31

Tungsten for Combustion Chamber of Turbo Engines


Tungsten for Combustion Chamber of Turbo Engines

What is Turbo Engines?

As we know, turbo engine is the heat engine which is conditioned by their maximum intake temperature, and it is limited by the behavior of the constituent materials of the articles that are most exposed to heat and constraints.

Why choose tungsten alloy?

Concerns for environmental protection have led designers of aviation turbo engines to search for means to reduce the proportion of pollutants in the exhaust gases of the engines. It is known that the principal problems in the matter of pollution of aviation turbo engines are, on the one hand, the emission of carbon monoxide, of hydrocarbons, and of various unburnt residues during operation on the ground and, on the other hand, the emission of nitrogen oxides and of particles during take-off and during cruising at altitude. There fore, tungsten alloy products are increasingly accepted by public in this case.

Conventional combustion chambers are generally of optimized rating for take-off or near take-off operation. This signifies that, in the primary zone of the combustion chamber, a fraction of the air flow of the compressor is introduced so that, with the injected fuel, the fuel-air mixture in this zone would be essentially stoichiometric in these modes. Under these conditions, due to the levels of temperature and high pressures, as complete as possible a combustion is obtained, combustion yields greater than 0.99 are attained, the speeds of the chemical reaction being optimum for these stoichimoetric mixtures.

In contrast, at low ratings, at idle or nearly so, the total richness in the chamber is only about half that at take-off; in addition, the pressures and temperatures at the outlet of the compressor are lower; the result is that the chamber, with the partial charge is very much maladjusted and that the slow speed combustion efficiency rarely goes beyond 0.93. The combustion is, therefore, very incomplete, which means much higher concentrations of carbon monoxide and unburnt residues at the exhaust than under normal operation. The proportions of the pollutants are all the higher, the lower the total yield of the combustion.

However, it appears to be possible to improve the performance of a combustion chamber by acting on four factors:

The timing of vaporization of the fuel,

The timing of the air-fuel mixture,

The timing of the fresh gas/burnt gas mixture,

The timing of the chemical reaction.

The first two times can be considered negligible at high ratings because of the pressures which are attained, but it is not so at low ratings. In fact, in order to increase the speed of the vaporization of the fuel, it must be transformed into fine droplets, which, in normal operation, is easily realized by the conventional mechanical atomizing injector, but the performance which is obtained in the lower ratings is poor. This is due to the fact that, if the fuel is well divided into droplets, these are poorly mixed with air in the primary zone and local zones would appear which have a richness which is too high. In the end, it would be necessary that each droplet would have around it the quantity of gas necessary for its vaporization and for its combustion, i.e., a quantity of gas which results in a stoichiometric mixture with the oxygen molecules after complete varporization. In order to accomplish this, systems such as aerodynamic injection have been proposed. Aerodynamic type injectors generally comprise whirling, or swirler vanes through which the air from the compressor is introduced, which serves to atomize the fuel. An air/fuel pre-mixture is thus obtained.

The fresh gas/burnt gas mixture must also be advantageous because it contributes to the increase in the temperature of the carburized mixture and, therefore, aids in its atomization and consequently permits an improvement in the speed of the chemical reaction. In conventionally allowing this contact of the carburized mixture with the high temperature gas from the combustion it is desirable to arrange for a recirculation of the latter by searching for a convenient turbulence level.

All of these solutions, which allow an improvement in the combustion yield have, however, a maximum efficiency only for values sufficient for the pressures and temperatures of the air at the chamber inlet.

As far as the reaction time is concerned, it is necessary to additionally research an optimization of the richness of the mixture, the ideal would be to be able to obtain a stoichiometric air/fuel proportion in the flame stabilization zone, regardless of the operation of the engine.

More details, please visit http://www.tungsten-alloy.com/turbo-engines.htm.


If you need any more details of the above news and/or products, please visit Chinatungsten Online, or contact us directly.
Disclaimer: The article is only reflecting the opinions of the author. We have no responsibility to prove the originality and authenticity of the content, words and/or pictures. You readers should just take it as reference and check the details by yourselves. And the content is not a suggestion for investment decision. The investor takes his or her own risks if he or she operates accordingly. If you have any dissent about the contents above, please contact the relevant author, or the webmaster. We will try our best to assist the dealing of the related issues. Thanks for your visit and cooperation.

ArticleInputer:Felicity    Editor:Felicity 
  • Back itemArticle:

  • Next itemArticle:
  • 【Font:Small Large】【Comment】【Add favorite】【Mail this page】【Print】【Close
    Links
    China Tungsten Online Molybdenum Tungsten Wire Tungsten Bars/Rods Tungsten Bucking Bar
    Tungsten Carbides Tungsten Heater Pure Tungsten Tungsten Carbide & Alloy Tungsten Paper weight
    Tungsten Heavy Alloy Tungsten Powder China Dart Wiki of WMo Infosys
    Darts Shop Online f2f.com.cn Xatcm Global InfoMine Stainless Steel Rails
    Sheet Metal Machinery Interactive Investor Link Exchange

    Add to FavoriteAbout CTIAContact UsMore LinksRecruitmentBusiness

    Address: 2-27B,No.261-265 Jiahe RD,Xiamen,Fujian 361009 P.R.China
    Phone:+86 592-5129696,+86 592-5129595;Fax:+86 592-5129797
    Sponsors: China Tungsten Industry Association,Chinatungsten Online
    Copyright © 2000 - 2009 Chinatungsten Online All Rights Reserved