Test Facility for High-Pressure Gas-Diesel Dual-Fuel Injectors

Increased use of natural gas in engines can lead to significant reductions not only in the automotive sector but also in applications involving medium-speed large engines, both in terms of climate-damaging carbon dioxide emissions and other engine-related pollutant emissions. By using a high-pressure direct gas injection strategy, the disadvantages of premixed gas combustion processes (e.g., in terms of efficiency) can be avoided. The goal of this research project was to develop high-quality testing capabilities for a systematic experimental investigation of the injection behavior of high-pressure gas injectors.

Test setups were developed for two measurement principles—a method for measuring pressure rise and a method for measuring the force of the injection jet—and fundamental and, in some cases, promising findings were obtained. In addition, a third measurement system—a prototype of the Injection Analyzer Pneumatic—was adapted to the requirements of large-engine gas injectors and successfully operated. On this basis, a test facility for the development of new high-pressure gas-diesel dual-fuel injectors was built and optimized. Measurements showed that injection rates can be measured with a high degree of accuracy. Test results based on variations in, for example, pressure, injection duration, and temperature provide valuable insights into injector behavior under different conditions. Furthermore, the test facility demonstrated its suitability for long-term operation.