Product category:
Materials Testing
News Release from: Michell Instruments | Subject: Optidew humidity measurement
Edited by the Manufacturingtalk Editorial
Team on 29 January 2007
Engine testing, development humidity
measurement
The measurement of humidity plays an important role in measuring the efficiency, power output and emissions of internal combustion engines.
The measurement of humidity plays an important role in measuring the efficiency, power output and emissions of internal combustion engines As an environmental requirement in the design and production of any combustion engine, including petrol and diesel motor vehicles, trucks, diesel locomotive engines, aircraft engines and gas turbines, a requirement exists to comply with the Clean Air Act
This article was originally published on Manufacturingtalk on 20 Aug 2008 at 8.00am (UK)
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Michell moisture control will dew nicely
Michell Instruments has released the SF Series, offering cost-effective control of moisture via dew point measurement.
Michell dew point meter has 250m cable
Now having an increased cable length of up to 250m, a dew point meter can be installed remotely to the electronics of the hygrometer, said Michell Instruments.
Testing is regulated by the Environmental Protection Agency (EPA) and the Californian Air Resources Board (CARB) in the USA and by various EC legislative standards in Europe.
Typical emissions which are monitored and regulated by various government agencies include NO, NO2, N2O4, SO2, SO3, CO, CO2, Pb and residual hydrocarbons.
The quality and relative concentrations of these emissions are affected by various factors, including ambient temperature, pressure, humidity and the type of engine, fuel and conditions of use.
Further reading
Trace moisture event sensor introduced
An on-line trace moisture event sensor designed for UHP inert gas applications in semiconductor fabrication provides rapid indication of a moisture event as low as 20 ppb at 1 ppb baseline.
Instruments company moves to new factory
Michell Instruments has moved into a custom-built factory that has a new service laboratory designed to provide the customer with the best possible service.
It follows therefore that in order to minimise variability of test results all influencing factors need to be controlled or measured wherever possible.
Studies carried out in the USA by the EPA (C D Paulsell, Moisture and Humidity, 1985: pp 735-744, Instrument Society of America) illustrate that the most successful method of determining the ambient humidity for the correction of the emissions concentrations is to use a cooled mirror dewpoint hygrometer.
Up until that time it was common for ambient humidity to be measured with a psychrometer.
Paulsell's research showed that such instruments are extremely prone to errors in measurement due to a wide variety of factors and, even if used under carefully controlled conditions, have no significant advantages over the use of a cooled mirror hygrometer.
The user should also be aware of the dangers of using capacitive type % rh probes that can be prone to drift and large measurement errors in such applications.
Michell Instrument's Optidew Dewpointmeter is the ideal product for this application.
The Optidew offers accurate and continuous measurement (within as little as 0.15 uC dew point) of the ambient dew point in an engine test cell and perhaps more importantly, the Optidew range is capable of extended service with full confidence and without measurement drift.
Every instrument is delivered fully calibrated and traceable to international standards (NPL, UK and NIST, USA) through Michell's UKAS accredited Humidity Calibration Laboratory.
This satisfies the most stringent of quality system requirements and gives ultimate confidence in the measurement made.
The Optidew has a measurement range to -40 uC dew point at normal room ambient temperature - more than enough to cope with any ambient humidity conditions. Request a free brochure from Michell Instruments ...
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