Some fundamental factors affecting the durability of coal/water slurry injectors in diesel engines

Conference · Sat Oct 01 04:00:00 EDT 1988

OSTI ID:6557159

Sekar, R R; Wang, C S; Choi, U S

The service life of an injector nozzle in a diesel engine fueled with a coal/water slurry (CWS) is 2-5 h, which limits the continuous running time of the engine. This study of CWS flow and erosion in injector nozzles was initiated to provide an analytical tool, validated by experiment, for designing a durable injector and predicting long-term wear from limited test runs. The two-phase hydrodynamic theory of solid/liquid slurry flow has been extended to incorporate the constitutive relationship for power-law non-Newtonian behavior. A computer model has been developed to predict the spatial and temporal variations in solid and liquid velocities, viscosities, and concentrations under the high shear rates encountered in diesel injection systems. The model has been validated using Newtonian, single-phase flow data obtained with water or No. 2 diesel fuel and non-Newtonian, two-phase flow data using a CWS. The computed and measured viscosities and shear rates showed good agreement. Viscosities of four micronized CWS samples were measured at shear rates between 3,000 and 30,000 sec/sup /minus/1/ in a high-pressure/high-shear capillary tube system or a rotational viscometer. The complex CWS flow at high shear depended on coal particle size, temperature, coal loading, additivies, and the shear rate. 22 refs., 14 figs., 4 tabs.

• Research Organization: Argonne National Lab., IL (USA)
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 6557159
• Report Number(s): CONF-881256-1; ON: DE89004198
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010402 -- Coal
Lignite
& Peat-- Purification & Upgrading
33 ADVANCED PROPULSION SYSTEMS
330102* -- Internal Combustion Engines-- Diesel
COAL LIQUIDS
COMPUTERIZED SIMULATION
DATA
DIESEL ENGINES
DISPERSIONS
ENGINES
FLOW MODELS
FLUIDS
FUEL INJECTION SYSTEMS
FUEL SLURRIES
FUEL SYSTEMS
FUELS
HEAT ENGINES
INFORMATION
INTERNAL COMBUSTION ENGINES
LIQUIDS
MATHEMATICAL MODELS
MIXTURES
NOZZLES
NUMERICAL DATA
PERFORMANCE TESTING
SIMULATION
SLURRIES
SUSPENSIONS
TESTING
VISCOSITY
WEAR