Accession Number : AD0439205

Title :   PISTON-SLAP NOISE IN RECIPROCATING MACHINERY,

Corporate Author : BOLT BERANEK AND NEWMAN INC CAMBRIDGE MASS

Personal Author(s) : Ungar,Eric E. ; Ross,Donald ; alvarez,Franklin F.

Report Date : 15 APR 1964

Pagination or Media Count : 105

Abstract : The most important component of mechanical noise of reciprocating machinery appears to be that due to piston-slap, i.e., due to the impacts associated with lateral piston motions across cylinder clearance spaces. This noise mechanism can account for several observed characteristics of diesel engine n ise not readily explained by the more popular theories which consider essentially only effects of cylinder gas pressure changes. The original calculations of piston impacts by V. I. Zinchenko did not consider connecting-rod inertias adequately, nor did they include considerations of the resulting vibratory and acoustic powers. Expressions for estimating vibrations and noise produced by piston-slap in any type of reciprocating machine are developed in this report. Comparisons are made between calculated and measured sound levels, and reasonable agreement is found. (Author)

Descriptors :   (*INTERNAL COMBUSTION ENGINE NOISE, PISTONS), (*PISTONS, INTERNAL COMBUSTION ENGINE NOISE), MOTION, VIBRATION, DIESEL ENGINES, MARINE ENGINES, SHIP NOISE, AUDIO FREQUENCY, THEORY, MATHEMATICAL ANALYSIS, COMPRESSOR NOISE, NOISE

Distribution Statement : APPROVED FOR PUBLIC RELEASE