Low Temperature Fresh Water Circuit Marine Aftercooler

Low temperature fresh water circuit marine aftercooler

Low Temperature Fresh Water (LT FW) circuit marine aftercooler, also named charge air cooler, is core heat exchange equipment for marine turbocharged diesel engines. It uses low-temperature closed fresh water as cooling medium to cool high-temperature turbocharged intake air, independent from high-temperature jacket water system, ensures stable low intake air temperature all year round.
Working Principle
Hot charge air from turbocharger (170~220°C) flows through air side of aftercooler
Constant low-temperature fresh water (32~42°C) circulates inside tube bundle
Heat transfers from hot air to low temp fresh water
Cooled air drops to 40~55°C into engine cylinder
Heated fresh water flows to central LT fresh water cooler for re-cooling, forms closed circulation loop
Core Structural Features
Type: Tube fin vertical horizontal type
Heat exchange tube: CuNi 90/10 / stainless steel seamless tube
Tube sheet: Carbon steel + copper nickel cladding, full expansion & welding

Main Design Parameters
Charge air inlet temperature: 170 ~ 220 °C
Charge air outlet temperature: ≤ 50 °C
Low temp fresh water inlet temp: 32 ~ 42 °C
Fresh water flow speed: 1.2 ~ 2.0 m/s
Air side working pressure: 0.35 ~ 0.55 MPa
LT fresh water side design pressure: 0.8 ~ 1.0 MPa
Allowable air side pressure drop: ≤ 5 kPa
Design thermal load: 35% ~ 42% engine rated power

Typical Matching Engines
Low speed marine main engine: MAN, WinGD, Wärtsilä
Medium speed marine auxiliary engine: Yanmar, Daihatsu, Mitsubishi, Caterpillar, Volvo Penta
Marine generator sets & marine power station engines

Application Scope
Container ship, bulk carrier, oil tanker, LNG ship, chemical tanker, offshore platform vessel, large engineering ship etc.