MDE Unit 13 Q3

A keel type cooling water system is a closed-loop cooling system used in marine applications. Unlike traditional systems that use a heat exchanger to transfer heat from the engine coolant to seawater, a keel cooling system directly exposes the coolant to seawater.  

1. Keel coolers eliminate silt, sand and seawater – Riviera Maritime Media

2. How Keel Cooling Works – R.W.Fernstrum & Company

How it works:

• Coolant circulation: Engine coolant is pumped through a network of tubes or channels integrated into the vessel’s hull, typically below the waterline.   1. Dry Exhaust Systems and Keel Cooling by Solé Advance soleadvance.com
• Heat transfer: The seawater in direct contact with the hull effectively cools the coolant as it circulates through the tubes.   1. Dry Exhaust Systems and Keel Cooling by Solé Advance soleadvance.com
• Return to engine: The cooled coolant is returned to the engine, maintaining optimal operating temperatures.   1. Dry Exhaust Systems and Keel Cooling by Solé Advance soleadvance.com

Advantages of Keel Cooling:

• Simplicity: Eliminates the need for a seawater pump and heat exchanger, reducing system complexity.   1. How Keel Cooling Works – R.W.Fernstrum & Company www.fernstrum.com
• Efficiency: Direct contact with seawater ensures efficient heat transfer.   1. Dry Exhaust Systems and Keel Cooling by Solé Advance soleadvance.com
• Reliability: Fewer components mean fewer potential points of failure.

Disadvantages of Keel Cooling:

• Vulnerability to damage: The external location of the cooling system makes it susceptible to damage from impacts or marine growth.
• Limited cooling capacity: The efficiency can be affected by factors such as water temperature and vessel speed.

While keel cooling offers advantages in certain applications, it’s essential to consider the specific operating conditions and vessel type before selecting this cooling system.

A keel type cooling system is relatively simple compared to traditional systems. The primary components are:

• Cooling water pipes: These are integrated into the ship’s hull, usually running along the keel.
• Coolant pump: Circulates the engine coolant through the pipes.
• Engine connections: Inlet and outlet pipes connecting the coolant system to the engine.
• Expansion tank: Accommodates coolant expansion and prevents system pressure build-up.   1. Expansion Tanks – Orca Marine Cooling Systems orcamarine.com

Note: While not a physical component, the ship’s hull itself acts as a heat exchanger in this system.

The expansion tank in a closed-loop cooling system can indeed be referred to as a header tank.

The term “header tank” is often used interchangeably with “expansion tank” in certain contexts. While the primary function is to accommodate coolant expansion, it can also serve as a collection point for the coolant.

While a traditional keel cooling system doesn’t have a separate expansion tank in the same sense as a closed-loop system, the concept of accommodating coolant expansion is still essential.

In a keel cooling system, the hull itself can act as a partial expansion chamber. However, due to the system’s design and the relatively small volume of coolant compared to larger closed-loop systems, the need for a dedicated expansion tank might be less critical.

Nevertheless, it’s essential to consider the following:

• Coolant level monitoring: Regular checks of the coolant level are crucial to ensure the system is operating correctly.
• Overfill prevention: Avoid overfilling the system to prevent coolant loss and potential issues.
• Air venting: If the system is prone to air pockets, a small vent or bleed point might be necessary.

In summary, while a dedicated expansion tank might not be a standard component in a keel cooling system, understanding the principles of coolant expansion and taking appropriate measures is essential for optimal system performance.

Vent lines are crucial components in various systems, including plumbing, HVAC, and industrial processes. Their primary function is to maintain proper air pressure and prevent system malfunctions.  

1. What Is A Plumbing Vent And What Does It Do? – A.B. May

Common purposes of vent lines:

• Preventing vacuum formation: As fluids (water, air, or other substances) move through a system, they can create a vacuum, which can hinder or prevent proper flow. Vent lines allow air to enter the system, preventing this vacuum.   1. What’s a Plumbing Vent Pipe and How Does It Work? trusteyman.com2. Drain-waste-vent system – Wikipedia en.wikipedia.org
• Releasing pressure: In systems that build up pressure, vent lines release excess pressure to maintain safe operating conditions.   1. Pressure Release Vents: A Must-Have for Any Industrial Setting | by Porvent – Medium medium.com
• Removing gases: In some systems, vent lines can be used to remove gases or vapors that accumulate.   1. How to Stop Sewer Smell from a Vent Pipe? – Ford’s Plumbing www.fordsplumbingandheating.com
• Facilitating filling: When filling a system with liquid, vent lines allow air to escape, preventing the formation of air pockets.

Examples of systems that use vent lines:

Industrial process equipment: To prevent equipment damage and ensure optimal performance.

Plumbing systems: To prevent sewer gases from entering homes and to ensure proper water drainage.   1. What’s a Plumbing Vent Pipe and How Does It Work? trusteyman.com

HVAC systems: To regulate air pressure in ducts and prevent system inefficiencies.

Automotive cooling systems: To release air bubbles and maintain coolant circulation.