Combustion-system processes leading to corrosive deposits

Conference · Thu Jan 01 04:00:00 EST 1981

OSTI ID:6372016

Stearns, C A; Kohl, F J; Rosner, D E

Degradation of turbine engine hot gas path components by high temperature corrosion can usually be associated with deposits even though other factors may also play a significant role. The origins of the corrosive deposits are traceable to chemical reactions which take place during the combustion process. In the case of hot corrosion/sulfidation, sodium sulfate has been established as the deposited corrosive agent even when none of this salt enters the engine directly. The sodium sulfate is formed during the combustion and deposition processes from compounds of sulfur contained in the fuel as low level impurities and sodium compounds, such as sodium chloride, ingested with intake air. In other turbine engine and power generation situations, corrosive and/or fouling deposits can result from such metals as potassium, iron, calcium, vanadium, magnesium, and silicon. Control strategies used to combat high temperature corrosion and fouling problems can be aided by improved understanding of the thermochemistry, kinetics, and dynamics of salt formation and deposition in the context of combustion system processes. The chemistry of sulfur and various metal salts in flame systems has been experimentally investigated. The flame chemistry has been related to deposition processes and corrosion. Deposition mechanisms have been studied, and deposition measurements have been made for a variety of systems. Deposition rate theories have been developed and evaluated. The theories have evolved from the simple transport of a single condensible vapor species to more general and accurate ones which include multicomponent vapor transport, thermal diffusion, variable gas properties across boundary layers, free stream turbulence, and particle size effects.

• Research Organization: National Aeronautics and Space Administration, Cleveland, OH (USA). Lewis Research Center; Yale Univ., New Haven, CT (USA). High Temperature Chemical Reaction Engineering Lab.
• DOE Contract Number: AI01-77ET10350
• OSTI ID: 6372016
• Report Number(s): DOE/NASA/2593-27; CONF-810347-3; NASA-TM-81752; ON: DE81024030
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360105 -- Metals & Alloys-- Corrosion & Erosion
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400800* -- Combustion
Pyrolysis
& High-Temperature Chemistry
ALKALI METAL COMPOUNDS
BIBLIOGRAPHIES
CHEMICAL REACTION YIELD
CHEMICAL REACTIONS
COMBUSTION
COMBUSTION PRODUCTS
COMBUSTORS
CORROSION
DEPOSITION
DEPOSITS
DOCUMENT TYPES
ENGINES
FLAMES
GAS TURBINE ENGINES
HEAT ENGINES
HIGH TEMPERATURE
INTERNAL COMBUSTION ENGINES
OXIDATION
OXYGEN COMPOUNDS
REVIEWS
SALTS
SODIUM COMPOUNDS
SODIUM SULFATES
SULFATES
SULFUR COMPOUNDS
THERMOCHEMICAL PROCESSES
YIELDS