摘要 |
A dynamometer is coupled to a single cylinder version of a multi-cylinder engine. The dynamometer control system calculates the instantaneous dynamic torques (e.g., inertial, combustion, and/or other torques) that would normally be generated in the multi-cylinder engine. The control system then inputs the torque from the missing cylinders of the engine to the dynamometer, preferably by a hydraulic system capable of accurately applying these torque pulses. By inputting energy to the engine as well as receiving it, the single-cylinder engine can replicate the rapid transients that are experienced in multi-cylinder engine operation, and can therefore be made to have an instantaneous speed profile matching that of the multi-cylinder engine. This allows testing of the single-cylinder engine at all engine speeds (including very low speed operation, which has traditionally been problematic), and also allows transient speed and load testing on single-cylinder engines, where such testing has heretofore been infeasible. The dynamometer thereby expands use of simpler, more versatile, and less expensive single cylinder test engines in place of multi-cylinder test engines, thereby decreasing the time and cost of engine research efforts.
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