Sierra - Model ExhaustTrak - Raw Exhaust Mass Flow Meter
Discover the benefits of direct in-situ exhaust measurement with ExhaustTrak. With our roots in flow measurement and automotive test, Sierra has developed ExhaustTrak, an innovative spin on a centuries old flow meter technology that solves one of today’s greatest flow measurements challenges.
- Go direct to the sample zone
- Innovative pressure averaging rings eliminate contamination issue
- Eliminating need for chemical mass balance methods
- Resolves temporal offset & instantaneous emissions error contributions vs. intake mass sources
- Reduced straight length requirements
- Meets or exceeds US EPA 40 CFR Part 1065
- Fuel H/C input, direct O2 measurement capability allows for molar weight compensation
Challenges of Direct Exhaust Measurement
- Hight Temperature
- Pressure Drop
- Particle-Laden Gases
The Indirect Solution
- Current indirect methods of exhaust flow measurement are fraught with uncertainty.
- Most common method estimates the flow using direct engine inlet air mass flow and chemical balance derived fuel mass to time-aligned gaseous emissions concentrations.
- This method is complicated
- Most importantly, it has little room for improvement in measurement accuracy and repeatability
Why Measure Exhaust Direct?
- Exhaust flow measurement, a critical input to emissions sampling
- Only solution to improve accuracy and repeatability
- Lower cost, real-time
- Legal and accurate
- Best for transient partial flow dilution proportional sampling
- Eliminate flow-related bias
- No sensitivity to upstream pneumatic capacitance
- Best option for raw transient emissions measurement