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We recommend that you use an intake-air flow meter that meets the specifications in Table 1 of § 1065.205. (ii ) For multiplying with continuously sampled gas concentrations, if the same signal is used in a chemical-balance calculation to determine work from brake-specific fuel consumption and fuel consumed. (i ) For feedback control of a proportional sampling system, such as a partial-flow dilution system.
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(2) In the following cases, you may use an intake-air flow meter signal that does not give the actual value of raw exhaust, as long as it is linearly proportional to the exhaust flow rate's actual calculated value: (iv ) For calculating the dilution air flow for background correction as described in § 1065.667. (iii ) For verifying minimum dilution ratio for PM batch sampling as described in § 1065.546. (ii ) For multiplying total raw exhaust flow with batch-sampled concentrations. (i ) For multiplying raw exhaust flow rate with continuously sampled concentrations.
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The following provisions apply for using intake air flow meters:
#Using a pitot tube if flowmeter is not working verification#
You may also use intake-air flow meters to determine the amount of intake air input for performing carbon balance error verification in § 1065.543 and to calculate the measured amount of intake air, n int, as described in § 1065.643. You may use intake-air flow meters in combination with a chemical balance of fuel, DEF, intake air, and raw exhaust to calculate raw exhaust flow as described in § 1065.655(f) and (g).