Development and utilization of new diagnostics for dense-phase pneumatic transport

Technical Report · Tue Jan 01 00:00:00 EST 1991

DOI:https://doi.org/10.2172/5174192· OSTI ID:5174192

Dense-phase pneumatic transport is an attractive means of conveying solids. Unfortunately, because of the high solid concentrations, this transport method is a difficult regime in which to carry out detailed measurements. Hence most details of the flow are unknown. In this context, the main objective of this work is to develop probes for local measurements of solid velocity and holdup in dense gas-solid flows. Because we anticipate the recent theories of rapid granular flows will bring insight to the dense pneumatic transport of particles, we have sought to substantiate these theories through computer simulations. There we have verified the theory of Hanes, Jenkins Richman (1988) for the rapid, steady shear flow of identical, smooth, nearly elastics disks driven by identical, parallel, bumpy boundaries. Because granular flows depend strongly on the nature of their interaction with a boundary, we have verified the boundary conditions calculated by Jenkins (1991) for spheres interacting with a flat, frictional surface. During the previous reporting period, we began a study of the time relaxation of the second moment of velocity fluctuations for a collection of disks undergoing simple shear. In the present reporting period, we have completed this study of relaxation by comparing results of simulations with the theoretical predictions of Jenkins and Richman (1988). In addition, we have concluded a series of experiments with flour plugs in the dense-phase pneumatic setup. Finally, we have established several industrial contacts to transfer the diagnostic techniques developed under this contract. 7 refs., 11 figs.

• Research Organization: Cornell Univ., Ithaca, NY (United States)
• Sponsoring Organization: USDOE; USDOE, Washington, DC (United States)
• DOE Contract Number: AC22-88PC88947
• OSTI ID: 5174192
• Report Number(s): DOE/PC/88947-T11; ON: DE92000337
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
47 OTHER INSTRUMENTATION
GRANULAR MATERIALS
PNEUMATIC TRANSPORT
VELOCITY
MEASURING INSTRUMENTS
COMPUTERIZED SIMULATION
FLOW MODELS
MULTIPHASE FLOW
OPTICAL FIBERS
PROBES
PROGRESS REPORT
QUANTITY RATIO
SHEAR
SOLIDS FLOW
TECHNOLOGY TRANSFER
DOCUMENT TYPES
FIBERS
FLUID FLOW
MATERIALS
MATHEMATICAL MODELS
SIMULATION
TRANSPORT
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440800 - Miscellaneous Instrumentation- (1990-)