Liquid Atomization, Sprays, and Fuel Injection

Liquid fuel atomization and spray formation is the heart of the majority of stationary and mobile power generation machines that we rely on. This seminar focuses on the process of liquid atomization and spray formation and how it relates to fuel injection systems and emission of pollutants in modern engines. The seminar begins with background coverage of terminology, the purposes of liquid atomization and spray formation, and different designs of atomizers and nozzles employed in various industries. The focus is then directed to gasoline and diesel fuel injections, injector designs, and performance requirements for optimum engine operation with lowest possible emission of harmful pollutants. Based on the idea that knowledge of technical practices and advances in one area (i.e. diesel fuel injection) is beneficial to engineers in other areas (gasoline direct injection, rocket engines), this seminar takes an interdisciplinary approach. Attendees will understand the technology and logic behind different injector designs, and gain the knowledge to judge, adapt and transfer technology advances from one discipline to another.

What Will You Learn

By attending this seminar, you will be able to:
  • Explain important terminology commonly used in atomization and sprays
  • Describe important processes in atomization and spray formation
  • Articulate the effects of injection system design and operating conditions on engine performance, combustion, and emission of pollutants
  • Describe different injector designs and the rationale for the use of each
  • Define the role the injection system plays in combustion and emission and how it is used to provide guidance in design of low-emission combustion systems
  • Implement appropriate design concepts and logic in the design of critical components such as intake valves and induction systems
  • Evaluate future trends and technology developments in fuel injection

Is This Course For You

Automotive and aerospace engineers, technical and project managers, researchers and academicians will benefit by attending this seminar. Automotive engineers working on the design of combustion engine components, reduction of harmful pollutants emissions, software development and application for modeling of thermal-fluid, combustions and emissions and engineers and managers directly involved in fuel injection systems will also benefit. Aerospace engineers involved in the design of gas turbine or rocket engines' combustion chambers will benefit as well.

Materials Provided

This data is not available at this time

Course Requirements

This data is not available at this time


  • Description of the Atomization Process
  • Disintegration of the Liquid Jets
    • Rayleigh criterion (no viscosity)
    • Weber's criterion (effects of viscosity)
    • Ohnesorge criterion for atomization (Ohnesorge Number)
    • Rayleigh, first and second wind-induced breakup and atomization regimes
    • Influence of some parameters -- jet velocity profile; nozzle length-to-diameter ratio; ambient pressure
    • Disintegration of liquid sheets
    • Drop breakup in air flow, turbulent flow, and viscous flow
  • Types of Atomizers: Pressure, Air-Assist, Air-Blast, Effervescent, Electrostatic, Ultrasonic, Diesel Injector and Gasoline-Fueled Injectors
  • Drop Size Distribution and Measurements
    • Graphical and mathematical representation of drop size distribution
    • Averaged diameter and representative diameters
    • Measurement techniques -- patternation; drop size measurements and spray characterization
    • Mechanical methods -- drop collection on slides; molten-wax and frozen-drop approach; cascade impactors; electrical; charged-wire and hot-wire methods; optical methods; imaging - photography and holography; single-particle light scattering (Phase Doppler Particle Analyzer, etc.); diffraction size analyzer
    • Drop evaporation
  • Diesel Fuel Spray, Injector and Injection System
    • Fuel injection system -- pumps: in-line injection, distributor-type injection, single-barrel injection, and unit injector & unit pumps; injector designs: nozzle holder, nozzles, others
    • Overall spray structure
    • Liquid fuel atomization
    • Spray angle
    • Intact core length
    • Spray evaporation
    • Ignition delay
    • Mixing-controlled combustion
    • HC emission mechanisms in diesel engines and its relation to fuel injection
    • Soot formation and fuel sprays
    • Advanced topics (details of split injection, common-rail injection, interacting-sprays injection, ultra-high pressure fuel injection, effects on performance and emissions, and others)
  • Gasoline Port Fuel Injectors and Injection System
    • Multipoint port injection system -- classes of gasoline port injectors: low pressure, medium pressure, high pressure, air-assisted, swirl, heated vaporizing, ultrasonic, and electrostatic; key requirements of gasoline port injectors; deposit considerations
    • Single-point throttle body injection system
    • Feedback system
    • Effects of injection parameters on engine performance and emission: injection timing, spray targeting, spray momentum, mean drop size, pulse-to-pulse variability, and others
  • Flow of Fuel and Air in Intake Manifolds
  • Details of Gasoline Direct Injection (GDI) and its Effects on Engine Performance and Emission of Pollutants
  • Fuel-air mixing processes
  • Spray Modeling and Demonstration of Computer Software for Spray Calculation in Engines
  • Summary and Conclusion