Toward Quieter Cooling Systems for Earthmoving Machines

Customer and regulatory forces are demanding quieter earthmoving and construction machines in many market segments -- a trend which is expected to intensify in the decade of the 90's. In many cases, the cooling system is a major contributor to the spectator sound power. Therefore, cost-effective means are required for reducing cooling system noise emissions.

This paper reviews strategies for cooling system noise reduction of earthmoving machines. Sources of cooling system noise and general noise reduction principles are outlined. Then, the impact of specific design countermeasures are discussed, including system size, ambient capability, heat loads, air system restriction, quieter components, and noise cover-up. Use of nondimensional parameters for fan selection are discussed. Finally, future design trends and areas for further investigation are identified.