The Smoke Nuisance Problem On Ships - A Review

Abstract

The ships are required to discharge overboard the products of combustion in the form of exhaust smoke. This is done through the funnel, which is usually located on topside of the ship. The ship’s funnel is expected to discharge the products of combustion in such a manner that they will stay clear of the ship. However, the contamination from smoke discharged from ship’s funnel has been found to manifest itself in the form of objectionable quantities of smoke coming down on topside operational areas. This is a problem for almost all vessels, regardless of type – be it the passenger liners, merchant ships or the naval ships. No smoke nuisance was encountered on ships with the classical high, narrow smokestacks. However, the modern trend towards short, bulky, streamlined funnels has frequently lead to smoke nuisance trouble on ships. The naval architect and ship designers are seized with the problem, which is not just confined to being able to dispose off the smoke in good fashion, but is also one of how to design a funnel in keeping with the modern aesthetic concepts as in case of passenger liners, or other constraints in locating the funnels as on naval ships, and still prevent the smoke from coming down on the deck. Over the years, the problem has been investigated in the wind tunnel, by analytical methods, by field measurements and recently, by CFD. The paper presents the evolution of the ship’s funnel over the last hundred years and reviews the study of the problem reported by various researchers since the 1930’s.