Marine engineering facts for kids

Marine engineers reviewing ship plans

Marine engineering is a type of engineering that focuses on designing, building, and maintaining boats, ships, submarines, and other vessels that travel on or under the water. It also includes designing structures and systems used in the ocean, sometimes called "ocean engineering."

This field uses many different types of engineering, like mechanical engineering, electrical engineering, electronic engineering, and computer science. Marine engineers work on things like a ship's engines, power systems, pipes, and control systems. They also work on structures found along coasts or far out in the ocean.

History of Marine Engineering

Many people see Archimedes as the first marine engineer. He created several important systems for ships in ancient times. Modern marine engineering really began during the Industrial Revolution in the early 1700s.

In 1807, Robert Fulton successfully used a steam engine to power a boat. His ship used the engine to turn a large wooden paddle wheel. This was the start of marine engineering as a profession. Just twelve years later, the SS Savannah made the first sea trip from America to Europe using steam power. About 50 years later, paddle steamers reached their peak with the SS Great Eastern. This ship was huge, about 700 feet long and weighing 22,000 tons, similar to today's large cargo ships! Paddle steamers were the main type of steamship for about 30 years until new ways of propulsion came along.

Why Marine Engineering Matters

The ocean is a huge part of life for almost everyone on Earth. It covers more than three-quarters of the planet's surface. About 80% of global trade by volume travels across the ocean on ships. Also, 99% of international digital messages, like internet data, travel through underwater cables. Plus, 40% of the world's population lives within 100 km (about 62 miles) of the coast.

The ocean is also vital for our environment. It holds most of Earth’s living species and provides much of our food. It also helps control the global climate. Because the ocean is so important, marine engineering works to find new ways to use it to help people.

Even though humans have a close connection with the ocean, much of it is still a mystery. Experts believe that 80% of the ocean floor has not been explored. More than 90% of ocean species are still unknown to science. Working on engineering projects in the ocean also brings many challenges. These include saltwater corrosion, strong water forces (fluid dynamics), remote locations, and extreme temperatures. Marine engineers must overcome these challenges to design successful ocean systems.

Related Engineering Fields

Naval Architecture

Naval architecture is about the overall design of a ship and how it moves through the water. Marine engineering makes sure that all the ship's systems work as they should. Even though they are different fields, naval architects and marine engineers often work closely together.

Ocean Engineering

Ocean engineering focuses on other structures and systems in or near the ocean. This includes offshore platforms (like oil rigs), coastal structures such as piers and harbors, and systems like ocean wave energy converters. It also includes underwater life-support systems. While ocean engineering is different from marine engineering (which focuses on ship systems), the two fields often overlap. Because they share similar names and many core skills, "ocean engineering" is sometimes considered part of "marine engineering," especially outside the U.S.

Oceanography

Oceanography is a science that studies the ocean by collecting and analyzing data. Marine engineering and oceanography are closely linked. Marine engineers often use data from oceanographers to help with their designs and research. In return, oceanographers use tools designed by marine engineers to explore and understand the ocean better.

Mechanical Engineering

Marine engineering uses many ideas from mechanical engineering. For example, mechanical engineers design the main engines and power systems for ships. They also design systems for steering, anchoring, handling cargo, heating, cooling, and communication. Marine engineers are responsible for installing these systems.

Understanding topics like how fluids move (fluid dynamics), how materials behave (strength of materials), and how structures react to forces is very important for marine engineers. These subjects are a big part of their education.

Civil Engineering

Civil engineering ideas are important in many marine engineering projects. This includes designing and building ocean structures, bridges and tunnels over or under the ocean, and port or harbor designs.

Coastal Engineering

Coastal engineering uses civil engineering and other skills to create solutions for areas along or near the ocean.

Electronics and Robotics

Marine engineering often involves electrical engineering and robotics. This is especially true when working with deep-sea cables and unmanned underwater vehicles (UUVs).

Deep-sea Cables

Long fiber optic cables connect much of the world's communication through the internet. These cables carry about 99% of all global internet traffic. They must be built to survive harsh deep-sea environments, with extreme pressures and temperatures. They also need protection from fishing, trawling, and sea life.

Underwater Robots

Unmanned underwater vehicles (UUVs) can benefit from smart computer programs and networks. Marine engineers study how new ideas in automation and networking can improve existing UUVs and help create more advanced underwater robots.

Petroleum Engineering

Knowing about marine engineering is helpful in petroleum engineering. Understanding how water moves (hydrodynamics) and how structures connect to the seabed is key for designing and maintaining offshore oil platforms.

Marine Construction

Marine construction is about building structures in or next to large bodies of water, usually the sea. These structures can be for many purposes, like transportation, making energy, or recreation. Marine construction uses materials like steel and concrete. Examples include ships, offshore platforms, pipelines, cables, wharves, bridges, tunnels, and docks.

Challenges in Marine Engineering

Hydrodynamic Loading

Just as civil engineers design buildings to handle wind, marine engineers design ships to handle millions of waves over their lifetime. These forces are also important in marine construction and coastal engineering.

Stability

Every ship needs to be stable in the water. A naval architect worries about a ship's stability. What makes their job special is that a ship operates in two fluids at once: water and air. Even after a ship is built, marine engineers must balance its cargo. Stacking containers too high can make the ship less stable. The weight of fuel also matters, as it can shift and cause imbalance. Some ships use ballast tanks filled with water to help balance. Marine engineers are in charge of balancing and tracking the fuel and ballast water on a ship. Floating offshore structures have similar balancing needs.

Corrosion

Saltwater is very harsh, making ships and marine structures prone to corrosion (rusting). Marine engineers always focus on protecting surfaces and preventing galvanic corrosion. One way to stop corrosion is by using "sacrificial anodes," which are pieces of metal (like zinc) that corrode instead of the ship's hull. Another method is to send a small electric current through the ship's hull. This changes its electrical charge and slows down rusting. Similar problems happen with coastal and offshore structures.

Anti-fouling

Anti-fouling is the process of removing unwanted organisms that attach to important parts of seawater systems. This is done in different ways:

• Marine organisms can grow on the inlets that bring water into cooling systems. Electrochlorination uses high electric current through seawater to create a chemical that cleans away bio-matter.
• Another method uses electricity with two metal anodes, usually copper and aluminum (or iron). The copper releases ions into the water, making it too toxic for marine growth. The aluminum coats the inside of pipes to prevent corrosion.
• Other marine growth, like mussels and algae, can stick to the bottom of a ship's hull. This makes the hull rough, slowing the ship down and making it use more fuel. Special paint can be used on the hull to prevent this growth.

Pollution Control

Sulfur Emissions

Burning marine fuels releases harmful pollutants into the air. Ships burn marine diesel and heavy fuel oil. Heavy fuel oil, being the thickest type of refined oil, releases sulfur dioxide when burned. Sulfur dioxide emissions can make the air and ocean more acidic, harming marine life. Because of the pollution it causes, heavy fuel oil can only be burned in international waters. It is cheaper than other fuels, but it is expected to be phased out of commercial use by 2020.

Oil and Water Discharge

Water, oil, and other substances collect at the bottom of a ship in an area called the bilge. Bilge water is pumped overboard, but it must pass a test to ensure it has less than 15 parts per million (ppm) of oil. If it's clean enough, it's discharged. If not, it goes back to a holding tank to be separated before being tested again. The oily water separator uses gravity to separate the liquids because they have different thicknesses. Ships over 400 gross tons must have equipment to separate oil from bilge water. Also, rules like MARPOL require all ships over 400 gross tons (and oil tankers over 150 gross tons) to record all oil transfers in an oil record book.

Cavitation

Cavitation happens when air bubbles form in a liquid because of a very low-pressure area. This low pressure can make the liquid turn into a gas. Cavitation can damage pumps that move fluids. It also happens with ship propellers. Low-pressure pockets form on the propeller blades as they spin faster. This causes small, violent implosions that can warp the propeller blade. To fix this, propellers can have more blades. This allows the same pushing force at a slower spinning rate. This is very important for submarines, as their propellers need to be quiet to stay hidden. More blades help the submarine move with less noise.

Applications of Marine Engineering

Arctic Engineering

When designing systems for the Arctic, like scientific equipment or oceanographic buoys, marine engineers face many challenges. Equipment must work in extreme cold for long periods, often without much maintenance. This means they need materials that can handle very low temperatures and durable electronic parts.

Coastal Design and Restoration

Coastal engineering uses civil engineering and other skills to create solutions for areas along the ocean. To protect coastlines from waves, erosion, and sea level rise, marine engineers decide whether to use "gray" infrastructure (like breakwaters or sea walls made of rocks and concrete) or "green" infrastructure (which uses aquatic plants, mangroves, or marsh ecosystems). Gray solutions cost more to build and maintain but might offer better protection in areas with strong waves. Green solutions are usually cheaper and blend better with nature, but they can be damaged if not done right. Often, engineers choose a mix of both.

Deep Sea Systems

Life Support

Designing underwater life-support systems, like underwater habitats, is very challenging. It requires detailed knowledge of pressure vessels, how diving affects the human body, and how heat works.

Unmanned Underwater Vehicles

Marine engineers often design or use unmanned underwater vehicles (UUVs). These robots operate underwater without a human on board. UUVs can work in places that are too deep, remote, or cold for humans. Some UUVs are controlled remotely by people, while others are fully autonomous (they can make their own decisions).

Sensors and Instruments

To study the ocean and find submarines, many special marine scientific instruments and sensors were developed. Light doesn't travel far underwater, so sound (Acoustics) is mainly used to send data. High-frequency sound measures ocean depth, maps the seafloor, and finds objects underwater. The higher the frequency, the clearer the data. Sonar was created during World War I to find submarines and has improved greatly since then. Submarines also use sonar to find other submarines, ships, and underwater obstacles like seamounts.

Simple echo-sounders point straight down to measure depth. More advanced echo sounders use fan-shaped or multiple beams of sound to create detailed images of the ocean floor. Powerful systems can even look into the soil and rocks beneath the seabed to learn about the geology. These are used to find oil and gas or for engineering surveys.

For short-range underwater communication, light can be used, mainly with blue lasers. These can send a lot of data quickly, but only for a few tens of meters, and ideally at night.

Besides acoustic communication and navigation, sensors have been developed to measure ocean conditions like temperature, salinity (saltiness), oxygen levels, and other properties. The trend is towards smaller, more accurate, and cheaper systems. This allows universities and smaller companies to use them, not just large corporations or governments. These sensors are put on autonomous and remote-controlled systems, as well as ships. They help these systems do tasks that used to require expensive human-crewed platforms.

Environmental Engineering

In every coastal and offshore project, protecting the environment is very important. This helps preserve ocean ecosystems and natural resources. Marine engineers use their knowledge of environmental engineering when creating fisheries, cleaning up oil spills, and developing coastal solutions.

Offshore Systems

Marine engineers design many systems that are used far from coastlines.

Offshore Oil Platforms

Designing offshore oil platforms involves many marine engineering challenges. Platforms must withstand ocean currents, wave forces, and saltwater corrosion. They also need to stay strong and firmly anchored to the seabed. Drilling parts must be designed with a high factor of safety to prevent oil leaks and spills that could harm the ocean.

Offshore Wind Farms

Offshore wind farms face many similar challenges to oil platforms. They provide renewable energy and can produce more power than land-based wind farms. They also face less public opposition.

Ocean Wave Energy

Marine engineers continue to explore ocean wave energy as a possible source of power for homes or the electrical grid. Many designs have been suggested, and prototypes built, but finding a cost-effective way to harness wave energy is still a challenge.

Port and Harbor Design

A marine engineer might also plan, create, expand, or change port and harbor designs. Harbors can be natural or man-made and protect ships from wind, waves, and currents. Ports are places where ships dock, load, or unload cargo. Ports are usually inside a harbor and have terminals for different types of cargo, like passengers, bulk cargo, or containerized cargo. Marine engineers plan and design different types of marine terminals and structures in ports. They must understand the forces these structures will face over their lifetime.

Salvage and Recovery

Marine salvage techniques are always being improved to recover shipwrecks. Marine engineers use their skills to help with different stages of this process.

Career in Marine Engineering

Industry Jobs

Marine engineers have a wide range of skills, allowing them to work in many different industries related to math, science, technology, and engineering. Some companies, like Oceaneering International, specialize in marine engineering. Other companies, like those in the oil industry (e.g., ExxonMobil and BP), hire marine engineers for specific projects, such as managing offshore drilling.

Military Roles

Marine engineering is also important for the military, especially the Navy. In the United States Navy, groups like the Seabees and Engineering Duty Officers often do work related to marine engineering. Military contractors (especially in naval shipyards) and the Army Corps of Engineers also play a role in some marine engineering projects.

Job Outlook

In 2012, the average yearly earnings for marine engineers in the U.S. were about $96,140. The field of marine engineering is expected to grow by about 12% from 2016 to 2026. Currently, there are about 8,200 naval architects and marine engineers employed, and this number is expected to reach 9,200 by 2026. This growth is partly because the shipping industry is crucial for global trade; 80% of the world's trade by volume moves overseas on nearly 50,000 ships, all needing marine engineers. Also, offshore energy is growing, and there's a greater need for coastal solutions due to sea level rise.

Education for Marine Engineers

Training Ship Golden Bear docked at California Maritime Academy.

Maritime universities focus on teaching and training students for jobs in the maritime world. Marine engineers usually earn a bachelor's degree in marine engineering, marine engineering technology, or marine systems engineering. Employers also value practical training alongside the degree.

Professional Groups

• IMarEST
• Society for Underwater Technology
• IEEE Oceanic Engineering Society
• Marine Engineering and Research Institute
• Indian Maritime University
• Royal Institution of Naval Architects (RINA)
• Society of Naval Architects and Marine Engineers (SNAME) – a global group started in 1893 that works to advance the maritime industry.
• American Society of Naval Engineers (ASNE)

Degrees in Ocean Engineering

Several universities, including MIT, UC Berkeley, the U.S. Naval Academy, and Texas A&M University, offer a four-year Bachelor of Science degree specifically in ocean engineering. These programs teach basic math and science (like calculus, statistics, chemistry, and physics), core engineering subjects (like statics, dynamics, electrical engineering, and thermodynamics), and specialized topics (like ocean structural analysis, hydromechanics, and coastal management).

Students pursuing advanced degrees (master's or PhD) in ocean engineering take more in-depth classes and do research for a thesis. The Massachusetts Institute of Technology (MIT) offers master's and PhD degrees in ocean engineering. MIT also has a joint program with the Woods Hole Oceanographic Institution for graduate students studying ocean engineering and other ocean-related subjects.

Amazing Marine Engineering Achievements

• The Delta Works is a series of 13 projects built to protect the Netherlands from flooding by the North Sea. The American Society of Civil Engineers called it one of the “Seven Wonders of the Modern World.”
• As of April 2021, twenty-two people have traveled to Challenger Deep. This is the deepest point in Earth’s ocean, found in the Mariana Trench.
• The recovery of the Soviet submarine K-219 by a team of U.S. Navy and CIA engineers aboard the Glomar Explorer.

Notable Marine Engineers

In Industry

• Pieter van Oord, CEO of Royal van Oord

In Academia

• Michael E. McCormick, a professor at the U.S. Naval Academy and a pioneer in wave energy research.

Marine Engineering in Media and Pop Culture

• Marine engineers played an important role in cleaning up oil spills like the Exxon Valdez and the British Petroleum spill.
• James Cameron’s documentary Deepsea Challenge tells the story of the team that built a special submarine. Cameron used it to make the first solo trip to Challenger Deep, the deepest spot in the ocean.

See also

In Spanish: Ingeniería naval para niños

• Engine room
• Engineering officer (ship)
• Marine architecture
• Marine electronics
• Naval architecture
• Oceanography