Masters Theses


"The objective of this research was to evaluate an air/fuel separation system known as a Fuel Preporator. The device's efficacy was determined by studying the effect of air entrainment on engine performance and fuel consumption of a General Motors 6.5 L naturally aspirated indirect injection (IDI) diesel engine. A test bed was developed to accommodate the test engine and test methods were adapted from federal regulations for steady-state engine testing (40 CFR 89 Subpart E). Cases of 0%, 5%, 10%, and 20% volumetric air entrainment were investigated for engine operation with and without the Fuel Preporator. Key measured engine performance parameters included fuel consumption, pre-chamber pressure, main cylinder pressure, and injection pressure. Key calculated engine performance parameters included brake specific fuel consumption (BSFC), indicated mean effective pressure (IMEP), and total heat release. The Fuel Preporator did not appear to affect fuel consumption. However, the measurement uncertainty associated with fuel mass flow rate increased with increased entrained air. The injection pressure traces for 0% and 10% entrained air were relatively consistent for engine test cases without the Fuel Preporator. However, the injection pressure trace shifted to the right when entrained air increased to 20%. Introduction of the Fuel Preporator advanced injection timing as much as three crank angle degrees. Furthermore, the injection pressure traces for 0%, 10%, and 20% air entrainment were overlaid. The shift in injection timing propagated to the cylinder pressure traces and also to the heat release rate. Despite the observed shift in injection pressure traces, BSFC, IMEP and total heat release were int influenced by the Fuel Preporator"--Abstract, page iii.


Drallmeier, J. A.

Committee Member(s)

Le, Vy Khoi
Flanigan, V. J.


Mechanical and Aerospace Engineering

Degree Name

M.S. in Mechanical Engineering


Missouri University of Science and Technology. Center for Environmental Science and Technology
United States. Department of Defense


Missouri University of Science and Technology

Publication Date

Fall 2010


xi, 134 pages

Note about bibliography

Includes bibliographical references (page 133).


© 2010 Michael Ray Hess, All rights reserved.

Document Type

Thesis - Open Access

File Type




Subject Headings

Diesel motor -- Combustion
Diesel motor -- Fuel consumption
Internal combustion engines
Motor vehicles -- Motors (Diesel)
Performance -- Testing

Thesis Number

T 9734

Print OCLC #


Electronic OCLC #


Link to Catalog Record

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