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Old 11-09-2016, 08:06 PM   #58
justatroll
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Quote:
Originally Posted by DSLeach View Post
I'm not going to continue this discussion because you clearly don't have the necessary education to understand the physics of this subject.

I'll just leave this here:


"SURFACE VEHICLE STANDARD

SAE J1349

7.5 Power and Torque Determination
7.5.1 TEST PROCEDURE
This section defines the actual dynamometer test procedure used in obtaining Rated Net Power and Torque. The test shall consist of a run at full throttle for spark-ignited engines and at a fixed full-load fuel injection pump setting for CI engines. The following test controls and operating conditions must be adhered to meet the requirements of this standard:
7.5.2 TEST POINTS
Measurements shall be taken at increments of no more than 500 RPM in sequence from the lowest to the highest engine speeds recommended by the manufacturer. The operating speeds shall include those for peak power and peak torque. Data at 100 RPM increments around peak torque and peak power are recommended to accurately distinguish their respective rated speeds. Engine speed shall not deviate from the nominal set speed by more than ±1% or 5 RPM, whichever is greater.

7.5.3 LOGGING OF MEASUREMENTS
No data shall be taken until torque and speed measurements have remained stable within 1% and controlled temperatures have remained stable within ± 2 C for at least 1 minute. The recorded measurements shall be the average of readings over a span of 1 minute. Alternatively, data can be taken by stabilizing the torque and speed for 5 seconds and then acquiring data at a minimum 10 Hz rate for at least ten seconds. If this alternative procedure is used, the entire speed sweep shall be repeated at least three times. The results are considered valid if the repeatability of at least three measurements is within 1% of the mean."

That says that (according to the definitive authority on automotive testing) that torque measurements are to be done at constant RPM.
So someone please tell me how rotational inertia can affect to torque produced at constant RPM?
(hint I already told you above)
If it is such simple physics, it should be a simple answer right?
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