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Notes

40 C.F.R. §§ 1065.220–1065.248

7 sections in range

§1065.220. Fuel flow meter.

40 C.F.R. § 1065.220

(a)
Application. You may use fuel 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). You may also use fuel flow meters to determine the mass flow rate of carbon-carrying fuel streams for performing carbon balance error verification in § 1065.543 and to calculate the mass of those fuel streams as described in § 1065.643. The following provisions apply for using fuel flow meters:
(1)
Use the actual value of calculated raw exhaust flow rate in the following cases—
(i)
For multiplying raw exhaust flow rate with continuously sampled concentrations.
(ii)
For multiplying total raw exhaust flow with batch-sampled concentrations.
(iii)
For calculating the dilution air flow for background correction as described in § 1065.667.
(2)
In the following cases, you may use a fuel flow meter signal that does not give the actual value of raw exhaust, as long as it is linearly proportional to the exhaust molar flow rate's actual calculated value:
(i)
For feedback control of a proportional sampling system, such as a partial-flow dilution system.
(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.
(b)
Component requirements. We recommend that you use a fuel flow meter that meets the specifications in Table 1 of § 1065.205. We recommend a fuel flow meter that measures mass directly, such as one that relies on gravimetric or inertial measurement principles. This may involve using a meter with one or more scales for weighing fuel or using a Coriolis meter. Note that your overall system for measuring fuel flow must meet the linearity verification in § 1065.307 and the calibration and verifications in § 1065.320.
(c)
Recirculating fuel. In any fuel-flow measurement, account for any fuel that bypasses the engine or returns from the engine to the fuel storage tank.
(d)
Flow conditioning. For any type of fuel flow meter, condition the flow as needed to prevent wakes, eddies, circulating flows, or flow pulsations from affecting the accuracy or repeatability of the meter. You may accomplish this by using a sufficient length of straight tubing (such as a length equal to at least 10 pipe diameters) or by using specially designed tubing bends, straightening fins, or pneumatic pulsation dampeners to establish a steady and predictable velocity profile upstream of the meter. Condition the flow as needed to prevent any gas bubbles in the fuel from affecting the fuel meter.
Notes, amendments, and revision history

Amendments

[70 FR 40516, July 13, 2005, as amended at 73 FR 37300, June 30, 2008; 76 FR 57441, Sept. 15, 2011; 81 FR 74162, Oct. 25, 2016; 86 FR 34536, June 29, 2021]

Authority

Authority: 42 U.S.C. 7401-7671q.

Source

Source: 70 FR 40516, July 13, 2005, unless otherwise noted.

Amendments

[70 FR 40516, July 13, 2005, as amended at 73 FR 37300, June 30, 2008; 76 FR 57441, Sept. 15, 2011; 81 FR 74162, Oct. 25, 2016; 86 FR 34536, June 29, 2021]

§1065.225. Intake-air flow meter.

40 C.F.R. § 1065.225

(a)
Application. 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). 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, nint, as described in § 1065.643. The following provisions apply for using intake air flow meters:
(i)
For multiplying raw exhaust flow rate with continuously sampled concentrations.
(ii)
For multiplying total raw exhaust flow with batch-sampled concentrations.
(iii)
For verifying minimum dilution ratio for PM batch sampling as described in § 1065.546.
(iv)
For calculating the dilution air flow for background correction as described in § 1065.667.
(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:
(i)
For feedback control of a proportional sampling system, such as a partial-flow dilution system.
(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.
(b)
Component requirements. We recommend that you use an intake-air flow meter that meets the specifications in Table 1 of § 1065.205. This may include a laminar flow element, an ultrasonic flow meter, a subsonic venturi, a thermal-mass meter, an averaging Pitot tube, or a hot-wire anemometer. Note that your overall system for measuring intake-air flow must meet the linearity verification in § 1065.307 and the calibration in § 1065.325.
(c)
Flow conditioning. For any type of intake-air flow meter, condition the flow as needed to prevent wakes, eddies, circulating flows, or flow pulsations from affecting the accuracy or repeatability of the meter. You may accomplish this by using a sufficient length of straight tubing (such as a length equal to at least 10 pipe diameters) or by using specially designed tubing bends, orifice plates or straightening fins to establish a predictable velocity profile upstream of the meter.
Notes, amendments, and revision history

Amendments

[70 FR 40516, July 13, 2005, as amended at 76 FR 57442, Sept. 15, 2011;79 FR 23760, Apr. 28, 2014; 81 FR 74163, Oct. 25, 2016; 86 FR 34536, June 29, 2021]

Authority

Authority: 42 U.S.C. 7401-7671q.

Source

Source: 70 FR 40516, July 13, 2005, unless otherwise noted.

Amendments

[70 FR 40516, July 13, 2005, as amended at 76 FR 57442, Sept. 15, 2011;79 FR 23760, Apr. 28, 2014; 81 FR 74163, Oct. 25, 2016; 86 FR 34536, June 29, 2021]

§1065.230. Raw exhaust flow meter.

40 C.F.R. § 1065.230

(a)
Application. You may use measured raw exhaust flow, as follows:
(1)
Use the actual value of calculated raw exhaust in the following cases—
(i)
Multiply raw exhaust flow rate with continuously sampled concentrations.
(ii)
Multiply total raw exhaust with batch sampled concentrations.
(2)
In the following cases, you may use a raw exhaust 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:
(i)
For feedback control of a proportional sampling system, such as a partial-flow dilution system.
(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.
(b)
Component requirements. We recommend that you use a raw-exhaust flow meter that meets the specifications in Table 1 of § 1065.205. This may involve using an ultrasonic flow meter, a subsonic venturi, an averaging Pitot tube, a hot-wire anemometer, or other measurement principle. This would generally not involve a laminar flow element or a thermal-mass meter. Note that your overall system for measuring raw exhaust flow must meet the linearity verification in § 1065.307 and the calibration and verifications in § 1065.330. Any raw-exhaust meter must be designed to appropriately compensate for changes in the raw exhaust's thermodynamic, fluid, and compositional states.
(c)
Flow conditioning. For any type of raw exhaust flow meter, condition the flow as needed to prevent wakes, eddies, circulating flows, or flow pulsations from affecting the accuracy or repeatability of the meter. You may accomplish this by using a sufficient length of straight tubing (such as a length equal to at least 10 pipe diameters) or by using specially designed tubing bends, orifice plates or straightening fins to establish a predictable velocity profile upstream of the meter.
(d)
Exhaust cooling. You may cool raw exhaust upstream of a raw-exhaust flow meter, as long as you observe all the following provisions:
(1)
Do not sample PM downstream of the cooling.
(2)
If cooling causes exhaust temperatures above 202 °C to decrease to below 180 °C, do not sample NMHC downstream of the cooling for compression-ignition engines, two-stroke spark-ignition engines, or four-stroke spark-ignition engines at or below 19 kW.
(3)
The cooling must not cause aqueous condensation.
Notes, amendments, and revision history

Amendments

[70 FR 40516, July 13, 2005, as amended at 79 FR 23761, Apr. 28, 2014]

Authority

Authority: 42 U.S.C. 7401-7671q.

Source

Source: 70 FR 40516, July 13, 2005, unless otherwise noted.

Amendments

[70 FR 40516, July 13, 2005, as amended at 79 FR 23761, Apr. 28, 2014]

§1065.240. Dilution air and diluted exhaust flow meters.

40 C.F.R. § 1065.240

(a)
Application. Use a diluted exhaust flow meter to determine instantaneous diluted exhaust flow rates or total diluted exhaust flow over a test interval. You may use the difference between a diluted exhaust flow meter and a dilution air meter to calculate raw exhaust flow rates or total raw exhaust flow over a test interval.
(b)
Component requirements. We recommend that you use a diluted exhaust flow meter that meets the specifications in Table 1 of § 1065.205. Note that your overall system for measuring diluted exhaust flow must meet the linearity verification in § 1065.307 and the calibration and verifications in § 1065.340 and § 1065.341. You may use the following meters:
(1)
For constant-volume sampling (CVS) of the total flow of diluted exhaust, you may use a critical-flow venturi (CFV) or multiple critical-flow venturis arranged in parallel, a positive-displacement pump (PDP), a subsonic venturi (SSV), or an ultrasonic flow meter (UFM). Combined with an upstream heat exchanger, either a CFV or a PDP will also function as a passive flow controller in a CVS system. However, you may also combine any flow meter with any active flow control system to maintain proportional sampling of exhaust constituents. You may control the total flow of diluted exhaust, or one or more sample flows, or a combination of these flow controls to maintain proportional sampling.
(2)
For any other dilution system, you may use a laminar flow element, an ultrasonic flow meter, a subsonic venturi, a critical-flow venturi or multiple critical-flow venturis arranged in parallel, a positive-displacement meter, a thermal-mass meter, an averaging Pitot tube, or a hot-wire anemometer.
(c)
Flow conditioning. For any type of diluted exhaust flow meter, condition the flow as needed to prevent wakes, eddies, circulating flows, or flow pulsations from affecting the accuracy or repeatability of the meter. For some meters, you may accomplish this by using a sufficient length of straight tubing (such as a length equal to at least 10 pipe diameters) or by using specially designed tubing bends, orifice plates or straightening fins to establish a predictable velocity profile upstream of the meter.
(d)
Exhaust cooling. You may cool diluted exhaust upstream of a dilute-exhaust flow meter, as long as you observe all the following provisions:
(1)
Do not sample PM downstream of the cooling.
(2)
If cooling causes exhaust temperatures above 202 °C to decrease to below 180 °C, do not sample NMHC downstream of the cooling for compression-ignition engines, two-stroke spark-ignition engines, or four-stroke spark-ignition engines at or below 19 kW.
(3)
The cooling must not cause aqueous condensation as described in § 1065.140(c)(6).
Notes, amendments, and revision history

Amendments

[70 FR 40516, July 13, 2005, as amended at 75 FR 23035, Apr. 30, 2010; 79 FR 23761, Apr. 28, 2014]

Authority

Authority: 42 U.S.C. 7401-7671q.

Source

Source: 70 FR 40516, July 13, 2005, unless otherwise noted.

Amendments

[70 FR 40516, July 13, 2005, as amended at 75 FR 23035, Apr. 30, 2010; 79 FR 23761, Apr. 28, 2014]

§1065.245. Sample flow meter for batch sampling.

40 C.F.R. § 1065.245

(a)
Application. Use a sample flow meter to determine sample flow rates or total flow sampled into a batch sampling system over a test interval. You may use the difference between a diluted exhaust sample flow meter and a dilution air meter to calculate raw exhaust flow rates or total raw exhaust flow over a test interval.
(b)
Component requirements. We recommend that you use a sample flow meter that meets the specifications in Table 1 of § 1065.205. This may involve a laminar flow element, an ultrasonic flow meter, a subsonic venturi, a critical-flow venturi or multiple critical-flow venturis arranged in parallel, a positive-displacement meter, a thermal-mass meter, an averaging Pitot tube, or a hot-wire anemometer. Note that your overall system for measuring sample flow must meet the linearity verification in § 1065.307. For the special case where CFVs are used for both the diluted exhaust and sample-flow measurements and their upstream pressures and temperatures remain similar during testing, you do not have to quantify the flow rate of the sample-flow CFV. In this special case, the sample-flow CFV inherently flow-weights the batch sample relative to the diluted exhaust CFV.
(c)
Flow conditioning. For any type of sample flow meter, condition the flow as needed to prevent wakes, eddies, circulating flows, or flow pulsations from affecting the accuracy or repeatability of the meter. For some meters, you may accomplish this by using a sufficient length of straight tubing (such as a length equal to at least 10 pipe diameters) or by using specially designed tubing bends, orifice plates or straightening fins to establish a predictable velocity profile upstream of the meter.
Notes, amendments, and revision history

Authority

Authority: 42 U.S.C. 7401-7671q.

Source

Source: 70 FR 40516, July 13, 2005, unless otherwise noted.

§1065.247. Diesel exhaust fluid flow rate.

40 C.F.R. § 1065.247

(a)
Application. Determine diesel exhaust fluid (DEF) flow rate over a test interval for batch or continuous emission sampling using one of the three methods described in this section.
(b)
ECM. Use the ECM signal directly to determine DEF flow rate. You may combine this with a gravimetric scale if that improves measurement quality. Prior to testing, you may characterize the ECM signal using a laboratory measurement and adjust the ECM signal, consistent with good engineering judgment.
(c)
Flow meter. Measure DEF flow rate with a flow meter. We recommend that the flow meter that meets the specifications in Table 1 of § 1065.205. Note that your overall system for measuring DEF flow must meet the linearity verification in § 1065.307. Measure using the following procedure:
(1)
Condition the flow of DEF as needed to prevent wakes, eddies, circulating flows, or flow pulsations from affecting the accuracy or repeatability of the meter. You may accomplish this by using a sufficient length of straight tubing (such as a length equal to at least 10 pipe diameters) or by using specially designed tubing bends, straightening fins, or pneumatic pulsation dampeners to establish a steady and predictable velocity profile upstream of the meter. Condition the flow as needed to prevent any gas bubbles in the fluid from affecting the flow meter.
(2)
Account for any fluid that bypasses the DEF dosing unit or returns from the dosing unit to the fluid storage tank.
(d)
Gravimetric scale. Use a gravimetric scale to determine the mass of DEF the engine uses over a discrete-mode test interval and divide by the time of the test interval.
Notes, amendments, and revision history

Amendments

[86 FR 34536, June 29, 2021]

Authority

Authority: 42 U.S.C. 7401-7671q.

Source

Source: 70 FR 40516, July 13, 2005, unless otherwise noted.

Amendments

[86 FR 34536, June 29, 2021]

§1065.248. Gas divider.

40 C.F.R. § 1065.248

(a)
Application. You may use a gas divider to blend calibration gases.
(b)
Component requirements. Use a gas divider that blends gases to the specifications of § 1065.750 and to the flow-weighted concentrations expected during testing. You may use critical-flow gas dividers, capillary-tube gas dividers, or thermal-mass-meter gas dividers. Note that your overall gas-divider system must meet the linearity verification in § 1065.307.
Notes, amendments, and revision history

Authority

Authority: 42 U.S.C. 7401-7671q.

Source

Source: 70 FR 40516, July 13, 2005, unless otherwise noted.