What Are The Application Scenarios For Marine Diesel Heat Exchanger Tube Bundles?
What are the Application Scenarios for Marine Diesel Heat Exchanger Tube Bundles?
Diesel engine cooling system
1. Fresh water cooling system (high temperature circuit)
Scenario: cooling of diesel engine cylinder liner, cylinder head, turbocharger and other high temperature parts.
Role:
The tube bundle serves as the heat exchange interface between fresh water (coolant) and seawater, transferring the heat carried by the high-temperature fresh water to the seawater, lowering the temperature of the fresh water, and circulating it back to the diesel engine for further cooling.
Avoiding the diesel engine from overheating, resulting in deformation of parts, lubrication failure or reduced combustion efficiency, to ensure the continuous and stable operation of the main engine.
2. Seawater cooling system (low-temperature circuit)
Scenario: cooling fresh water, lubricating oil, compressed air and other media in the fresh water system.
Role:
The tube bundle directly utilizes the outboard seawater as the cold source, and transfers the heat of fresh water, lubricating oil and other media to seawater through the heat exchanger tube to realize the secondary cooling.
The low temperature and high flow characteristics of seawater make it an efficient heat dissipation medium, especially suitable for the heat dissipation needs of high-power diesel engines.
Lubricating oil system
1. Lubricating oil cooling
Scenario: cooling of diesel engine crankcase lubricating oil, supercharger lubricating oil, gearbox lubricating oil.
Role:
Lubricating oil absorbs mechanical friction heat and combustion heat in the lubrication process, and the viscosity decreases and lubrication performance is weakened after the temperature rises.
The tube bundle reduces the lubricant temperature through heat exchange, maintains its viscosity and lubrication effect, reduces mechanical wear and prolongs the life of the equipment.
Fuel System
1. Fuel oil preheating
Scenario: Preheating of heavy fuel oil (HFO) or poor quality fuel before combustion.
Role:
Heavy fuel oil has high viscosity and needs to be heated to a specific temperature (e.g. 120-150°C) to reduce viscosity for pumping and atomized combustion.
The tube bundle uses the waste heat of the diesel engine cooling system (such as high-temperature fresh water) or steam as the heat source, and heats the fuel through the heat exchanger tube to realize energy recycling and reduce fuel consumption.
Compressed air system
1. Air compressor after cooling
Scenario: Cooling of high-temperature compressed air output from ship's air compressor.
Role:
The temperature of compressed air rises during the compression process and needs to be cooled to room temperature through the tube bundle to avoid damage to the downstream equipment (e.g. cylinder starter valves, instruments) caused by high temperature air.
At the same time, the cooling process can condense the moisture in the air, discharged through the separator, to improve the cleanliness of compressed air.
Other auxiliary systems
1. Domestic hot water supply
Scenario: Utilizing the waste heat from the diesel engine cooling system to heat the ship's domestic water.
Role:
The heat of high-temperature fresh water is transferred to the domestic water pipeline through the tube bundle, realizing free hot water production, reducing the ship's dependence on independent heating equipment and lowering energy consumption.
2. Exhaust gas boiler system (indirect application)
Scenario: diesel exhaust gas waste heat recovery (such as exhaust gas boiler to produce steam).
Role:
Although the heat exchanger element of the exhaust gas boiler is usually a flue pipe or water pipe, part of the system may be a secondary heat exchanger between the steam and other media (e.g., fuel oil, fresh water) through a tube bundle to achieve multi-stage utilization of heat.
