Fundamental Investigation of Jet Fuel Spray and Ignition Process in an Optically Accessible Piston Engine

Abstract

Effects of transient rate-of-injection (ROI) fuel sprays on jet development and combustion were measured in a compression-ignition direct injection optical engine. Jet penetration, liquid length, jet dispersion angle, liftoff length, and engine cylinder pressure data were simultaneously acquired over a range of engine operating conditions relevant to the design of Army engines. Tests were performed using #2 diesel fuel, jet fuel (JP8), and a hydroprocessed renewable jet fuel (HRJ). Ambient thermodynamic conditions and fuel injection parameters had similar effects on combustion and jet performance in the optical engine as in previous results from constant volume chambers. The ramp-on transient from the opening of the fuel injector caused the scaling of jet parameters with time during the transient ROI to be modified from relationships expected from the literature. Similarities were seen in a comparison between the jet velocity, the derivative of the ROI and the derivative of a curve fit created to model the data taken. In the long-time limit, these injections were seen to return to their quasisteady forms, with the changes in jet parameters occurring during the initial opening of the injector. The results show the need to resolve the initial transient injection process in small bore diesel engines.

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Document Details

Document Type
Technical Report
Publication Date
Jan 16, 2015
Accession Number
ADA622168

Entities

People

  • David A Rothamer
  • Nicholas Neal

Organizations

  • University of Wisconsin–Madison

Tags

Communities of Interest

  • Energy and Power Technologies
  • Materials and Manufacturing Processes

DTIC Thesaurus Topics

  • Burning Rate
  • Chemical Reactions
  • Combustion
  • Combustion Chambers
  • Compression Ignition
  • Compression Ignition Engines
  • Diesel Engines
  • Diesel Fuels
  • Engine Cylinders
  • Exothermic Reactions
  • Fuel Injection
  • Heat Of Combustion
  • Heat Transfer
  • Ignition
  • Ignition Lag
  • Internal Combustion Engines
  • Refractive Index

Fields of Study

  • Physics

Readers

  • Combustion and Flow Dynamics.
  • Petroleum Engineering