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Voice of the Customer: Flow Meter Solution for Air Pollutant Measurement

Nov 15, 2013

We’re always looking for solutions here at Sierra-ones that always give customers precise, accurate data. It’s what drove Dr. John G. Olin to found Sierra in 1973, with a goal of providing the marketplace with accurate flow meter measurement. It’s what drives our engineering team to continue to advance flow meter design. It’s also what drives them to support customers and reps with truly turnkey OEM solutions.

So, when Dr. Tony Hansen, founder of Magee Scientific in Berkeley, CA, came to us with a request for a low-cost solution for equipment that would essentially help thousands, we were happy to assist. Hansen was developing a device called an Aethalometer® to measure black carbon levels in the air thought to be related to climate change as well as air pollution.

Carbon Soot Aethalometer (South Pole)

To follow up on his progress, we asked Dr. Hansen a few questions about how his work provides accurate data to learn more about climate change and air pollution.

1. Describe your area of expertise. We manufacture a scientific instrument that measures air pollution by “black carbon” particles—now shown to be the No. 2 cause of global climate change. We also engage in scientific and technical research to improve the measurement of this pollutant.

2. What problems have you been attempting to tackle with your current or recent research studies?

Measurement of air pollution at challenging locations, including the:

  • South Pole. -50°C, 3200 m. altitude, extremely clean air, zero humidity.

  • South China and India. Extremely polluted air, very high ambient humidity, very dirty working environment.

3. Walk us through the process you went through to address this issue. What were the flow measurement concerns associated with your research?

Correct calculation of the concentration of pollution is based upon correct knowledge of the amount of air drawn through the instrument during each measurement period. Typical flow rate is 5 LPM; typical analytical period is 1 to 5 minutes. Our end users require data expressed either in Standard units (SLPM) or in “local” units, where the “local” cubic meter depends on T & P. Our instrument has a separate T & P sensor, which we use to convert the ‘Standard’ (mass) flow data.

4. What flow meter and/or controller equipment helped you during the research process? How did it impact the accuracy of your conclusions? We use the Sierra Top Trak mass flow meter, with a range of 0~10 SLPM air. The flow meter signal is combined with the user’s set point to control the speed of the BLDC variable-speed pump. In this way, we were able to program the desired flow, and the instrument automatically stabilizes at that set-point. Ours is an OEM application, so we didn’t need any display or external features. We’ve used this same flow meter for years now, and it is ideal for our application.

5. What has been the impact of this research on your company or the industry at large?

Our instrument is the de-facto standard for measuring black carbon air pollution. Our users have to feel confident that they can trust the numerical data. The data calculation depends intrinsically on the accuracy of the air flow measurement.

How has Sierra helped you solve your flow measurement problems? Tell us in the comments below. And also download our Clean Energy Guide to see how Sierra has partnered with companies from around the globe to help solve environmental concerns.

Erica Giannini, Marketing Manager
Written By:
Erica Giannini, Marketing Manager
Sierra Instruments

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