LEAK TESTING · ENGINEERING CALCULATOR
Estimate helium throughput from concentration increase in the free volume of an outer collection enclosure.
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Model
Calculate
Assumptions and use
Assume a well-mixed enclosure, stable temperature and pressure, known free volume and negligible tracer losses. Check sampling losses, background drift, enclosure leakage and accumulation timing. The concentration correction assumes the stated tracer conditions; it is not a universal flow-regime conversion.
Worked example
For 10 L at 100000 Pa, a rise of 10 ppm in 100 s gives 1e-4 Pa·m³/s of helium.
Record the units, gas, temperature, background and instrument settings with every result. Confirm the model assumptions before applying a calculated limit to a real test.
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