Sierra Instruments, Inc.

- Raw Exhaust Mass Flow Meter

From

0

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.

Joining ExhaustTrak with the BG3 Elite Partial Flow Sampling System creates a major breakthrough as a “Dynamic Duo” is formed.  BG3 Elite and ExhaustTrak, working together, are a technically equivalent, commercially available replacement of full flow CVS systems for partial flow PM and raw or dilute gaseous emissions sampling methods for Light Duty. Learn more...  

BG3 Elite provides the accurate and repeatable Partial Flow Dilution (PFD), but it needs ExhaustTrak to resolve temporal and dispersion flow rate offsets versus intake air by measuring real time mass flow at the emissions sampling zone.

  • Go direct to the sample zone 
  • Patented pressure averaging rings for zero contamination
  • Eliminating need for chemical mass balance methods
  • Meets or exceeds US EPA 40 CFR Part 1065
  • BG3 with ExhaustTrak replaces full flow CVS for Light Duty-

  • Eliminates need for chemical balance mass methods
  • Eliminate flow-related bias
  • Resolves temporal offset vs. intake mass sources through direct measurement sampling zone
  • Exhaust flow measurement is a critical input to emissions sampling
  • The direct method is the only solution to improve accuracy and repeatability
  • Lower cost, real-time
  • Legal and accurate
  • No sensitivity to upstream pneumatic capacitance
  • Best option for raw transient emissions measurement

ExhaustTrak is designed to satisfying customer requirements for a rugged, accurate and fast solution for direct exhaust mass flow measurement.  The mass flow meter is specifically designed for transient cycle flow rate measurement and can measure the mass flow rate of intake air flow, diluted exhaust, raw exhaust (pre or post-aftertreatment), or crankcase combustion fumes, since instrumentation pressure line plugging issues no longer exist.

Taking clues from our use of porous media (sintered stainless steel) in our patented partial flow dilution tunnel utilized by the BG3, we use circumferential porous media as pressure interface material to elevate subsonic venturi flow meter technology to a whole new level. The design provides fully averaged radial pressure sampling at the throat and the inlet locations. Flow inaccuracies due to velocity profile skew are minimized.

As a result, straight length requirements for installing the ExhaustTrak are relaxed, as it is nearly immune to bias effects created by bend-induced swirl.

Challenges of Direct Exhaust Measurement
  • Hight Temperature
  • Moisture
  • Pulsations
  • Turndown 
  • Pressure Drop
  • Particle-Laden Gases

  • Eliminates need for chemical balance mass methods
  • Provides accurate, real-time exhaust mass results
  • Meets or exceeds US EPA 40 CFR Part 1065 requirements
  • Rugged, accurate, & fast – excellent for transient & steady-state testing
  • Sub-Sonic Venturi Technology (Patent Pending)
  • Measurement of particle-laden exhaust streams applicable to raw or diluted exhaust, crankcase fumes or combustion air

  • Eliminates instantaneous emissions error contributions due to indirect vs. direct exhaust mass flow determination
  • Fuel H/C input, direct O2 measurement capability allows for increased accuracy with real-time exhaust molar weight compensation
  • Proportional analog signal output for PM sampling devices such as BG3 PFD
  • AK digital communication for host integration
  • Fully averaged radial pressure sampling
  • Porous media as pressure interface
  • No plugging issues
  • Reduced straight length requirements
  • Wide range of flow rate capabilities available

  • Venturi Size - 1-inch to 8-inch OD Standard
  • Absolute Pressure: up to 200 kPa Standard
  • Tempeature: up to 950°C Standard
  • Maximum Flow Rates (500°C, 1 atm): 50 kg/hr - 6000 kg/hr Standard

Challenges of Direct Exhaust Measurement

  • Hight Temperature
  • Moisture
  • Pulsations
  • Turndown 
  • 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

Customer reviews

No reviews were found for Sierra ExhaustTrak - Raw Exhaust Mass Flow Meter. Be the first to review!