Influence of various factors on air pressure pulse from trains passing by each other

Based on the results of numerical computation, full scale tests and wind tunnel tests,the investigations have been made on the dependence of air pressure pulse from two trains passing by each other on the following influence factors: the relative speed, absolute speed, speed ratio, track interval, train shape (section figuration, length and broadness ratio of streamlined head, largest outline of head longitudinal section and largest outline of head horizontal view) and the train formation. These investigating conclusions have been used for train designing with streamlined head figuration in our country and can present a foundation for determining the reasonable track interval.