Resistance of a Freight Train to Forward Motion. Volume II: Implementation and Assessment

摘要

The report is a supplement to a previous report and documents the results of the second portion of an investigation of the train resistance phenomenon. This portion of the effort was specifically directed toward determination of possible fuel savings to be effected through certain design improvements or equipment modifications when a freight train is operated over normal track, including grades and curves. The results of 52 simulated runs of various freight trains over various tracks, both real and artificial, are reported. The simulations show that fuel savings are not directly proportional to reductions in train resistance and that under certain circumstances only a portion of the theoretically attainable fuel savings can be achieved. It is also shown that fuel savings can be achieved. It is also shown that fuel savings attributable to certain of these modifications are quite dependent upon the nature of the operation in which they are used. Within limits, the computer program developed during this study can be used to determine the fuel consumption of an arbitrary train operated over an arbitrary track to perform sensitivity analyses with respect to locomotive assignment policy, operational speed limit, and the like, and to determine the effect of design improvements or equipment modifications upon fuel consumption under normal operating conditions. The computer program which performs the calculation is explained in detail and the rationale behind its development is given.