1996-10-01

Experimental Determination of the Instantaneous Frictional Torque in Multicylinder Engines 962006

An experimental method for determining the Instantaneous Frictional Torque (IFT) using pressure transducers on every cylinder and speed measurements at both ends of the crankshaft is presented.
The speed variation measured at one end of the crankshaft is distorted by torsional vibrations making it difficult to establish a simple and direct correlation between the acting torque and measured speed. Using a lumped mass model of the crankshaft and modal analysis techniques, the contributions of the different natural modes to the motion along the crankshaft axis are determined. Based on this model a method was devised to combine speed measurements made at both ends of the crankshaft in such a way as to eliminate the influence of torsional vibrations and obtain the equivalent rigid body motion of the crankshaft. This motion, the loading torque and the gas pressure torque are utilized to determine the IFT.

SAE MOBILUS

Subscribers can view annotate, and download all of SAE's content. Learn More »

Access SAE MOBILUS »

Members save up to 16% off list price.
Login to see discount.
Special Offer: Download multiple Technical Papers each year? TechSelect is a cost-effective subscription option to select and download 12-100 full-text Technical Papers per year. Find more information here.
We also recommend:
TECHNICAL PAPER

Determination of the Gas-Pressure Torque of a Multicylinder Engine from Measurements of the Crankshaft's Speed Variation

980164

View Details

TECHNICAL PAPER

SI-Engine Cylinder Pressure Estimation using Torque Sensors

2004-01-1369

View Details

TECHNICAL PAPER

Numerical Analysis of Fuel Behavior in a Port-Injection Gasoline Engine

970878

View Details

X