Developing Fuel Injection Strategies for Using Ammonia in Diesel Engines

Grant # 08F-01
Principal Investigator: Song-Charng Kong
Organization: Iowa State University
Technical Area: Renewable Energy

Public Abstract

Ammonia combustion does not produce carbon dioxide, a known greenhouse gas that contributes to global warming. In order to use ammonia in a diesel engine, simplicity of the fuel system and efficient combustion are critical. Our research group has demonstrated the successful operation of a diesel engine using ammonia with a dual-fuel approach. During operation vapor ammonia was inducted into the engine intake manifold and diesel fuel was injected into the cylinder to initiate ammonia combustion. Despite the feasibility of using ammonia to replace diesel fuel, the exhaust ammonia concentration was at the level of thousands of ppm partly due to the continuous induction of vapor ammonia that was not synchronized with the transient nature of the engine cycle. This lack of fuel control needs to be improved, and thus research is required to develop fuel injection strategies to help adopt ammonia in diesel engines and improve the combustion efficiency.

Our long-term goal is to develop enabling technologies for adopting ammonia in diesel engines to replace petroleum fuels and reduce greenhouse gas emissions. An objective of this project is to evaluate the feasibility of liquid ammonia injection to reduce the complexity of the fuel system. A second objective is to characterize engine performance using various injection strategies to achieve high efficiency and low emissions. Our rationale is that the fuel economy of the ammonia-diesel system needs to comparable to that of the regular diesel engine in order to be competitive. Our research team has extensive experience in operating a diesel engine using ammonia, and our engine research laboratory is equipped with the state-of-the-art engine testing facility to complete this project.

Building upon this project, we expect to develop strategies for using ammonia in diesel engines with viable injection strategies and high combustion efficiency. These strategies can be adopted in real-world engine operation to enable the wise-spread use of ammonia for power generation. This work will be the first study that investigates the fuel injection and engine operating parameters for optimal diesel engine performance using ammonia. The completion of this project will help reduce our dependence on petroleum fuels and move our nation toward energy independence.