Mixed flowing gas

The oxygen balance for the well-mixed flowing gas phase is described by dCc... 

The disadvantages are that (1) they are not suitable for services that are dirty, abrasive, viscous, or mixed-flow (gas with liquid droplets, liquid with vapor bubbles), or that have low Reynolds numbers (below 20,000) (2) the available choices in materials of construction are limited (3) the pulse resolution (number of pulses per gallon or liter) drops off in larger sizes (4) the pressure drop is high (two velocity heads) and (5) substantial straight runs are required, both upstream and downstream. 

Standard Practice for Conducting Mixed Flowing Gas (MFG) Environmental Tests... 

The Mixed Flowing Gas Test, ASTM B 827, is used extensively in the electronics industry. As the name implies, the test method uses a combination of various gases at controlled temperatures and humidities to produce the desired conditions. The MFG test requires equipment of a more complex nature than other corrosive gas tests. A schematic of a typical chamber is shown in Fig. 3b, as depicted in ASTM B 827. 

Abbott, W. H., "The Development and Performance Characteristics of Mixed Flow Gas Test Environment, IEEE Transactions on Components, Hybrids, and Manufacturing Technology, Vol. 11, 1988, pp. 22-35. 

TABLE 7—Mixed flowing gas test conditions for electronics corrosion. 

TABLE 8—Standards for mixed flowing gas tests and associated measurements. 

This approach is useful if the environment is well characterized and a few weeks or months have been allocated for the test examples include exposure to salt spray to simulate sea coastal areas, exposure to 3.5 wt% NaCl solution for submarine environment, Kesternich chamber test (humid SO2 and CO2 mixture) for industrial environment [6], and mixed flowing gas tests for a range of environments. 

Practice for Conducting Mixed Flowing Gas (MFG) Environmental Tests Standard Test Method for Resistance of Zippers to Salt Spray (Fog)... 

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