Combustion Analysis
The demand for lower emissions, increased fuel economy, improved reliability and overall better performance has become the driving force behind the increased levels of technology in today’s internal combustion engines. Development and calibration engineers tasked with integrating this technology need to utilize best-in-class tools to meet the many goals of a development project. One of the most effective of these tools is a high-quality combustion analysis system.
Challenges
Every new feature exponentially increases the number of variables which have to be optimized over the engine’s operational range. This process is highly iterative, sometimes taking months to accomplish. A combustion analysis system can help to automate this process by providing instantaneous evaluation of the combustion event,allowing the effects of changes to the control strategy to be seen immediately,without post processing.
Engine development challenges are not limited to the test bed. Combustion related problems can also be found in production platforms. Issues such as misfires, knock and mechanical noise can sometimes only be observed in a vehicle with the full powertrain. The availability of a compact DC-powered in-vehicle combustion analysis system can be an essential tool in determining the source of the issues.
The A&D Solution
A&D’s Phoenix combustion analysis systems uses in-cylinder piezoelectric transducers to measure the pressures throughout the entire engine cycle. Cylinder pressure measurements are then analyzed simultaneously with data acquisition providing analysis results for display and logging while the engine is operating. Instantaneous availability of combustion results facilitates the implementation of automated calibration and optimization.
The Phoenix system includes other features such as crank position sensor signal interpolation, self powered charge amplifiers and 12 volt DC operation which makes it ideal for in-vehicle applications. The availability of immediate results can be used to properly set start-up fuel and ignition timing, calibrate knock detection, and validate misfire indication.
A&D’s Phoenix systems include all the software necessary to perform standard tests required to properly evaluate combustion processes in two or four stroke, spark or compression ignited engines. Features built into the Phoenix systems include:
- Start-up test mode for evaluating engine cold-start strategy
- Knock detection and indication to protect the engine and increase reliability
- Data Acquisition with a fixed time base
- Crank position sensor/ engine-mounted encoder for flexible DAC methods
- Automation system interface for implementing closed-loop test cell control
- Post processing for post-test analysis
