Turbo jet engine

Types of turbo jet engines

A turbo jet engine is a type of aircraft engine that uses a rotary compressor driven by a turbine to compress incoming air, mix it with fuel, ignite the mixture to create a high-pressure, high-temperature gas, and then release it out the back to create thrust. Generally, there are some types of turbo-jet engines, including Double Spool Turbojet Engines, Single Spool Turbojet Engines, and LPG Turbojet Engines.

• Double spool turbojet engines: A Double Spool Turbojet Engine has two spools or axles that compress air. The spools consist of a compressor linked to a turbine. This engine model also features a ducting system that directs the high-pressure exhaust. The double spools work independently, allowing for a more efficient process of compressing air and extracting energy from the exhaust. This improves the engine's performance and fuel economy, making it better for flying high and fast.
• Single spool turbojet engines: Single spool turbojet engines are simpler than double spool engines. They have one axle that links a compressor and a turbine. The turbine gets the energy to spin from the exhaust gas of the compressor. This basic setup lets the engine work well to compress air and generate power. Compared to more complex engines, single spool turbojets are lighter and easier to build, making them suitable for smaller aircraft and simpler designs where less weight is important.
• LPG turbojet engines: LPG (Liquefied Petroleum Gas) turbojet engines work like regular turbojet engines but use LPG as fuel. The basic structure of an LPG turbojet includes air intake, compression, combustion, turbine, and exhaust. Operating on the same principle as a standard turbojet engine, an LPG turbojet engine converts the chemical energy of burning LPG into mechanical energy and thrust by burning the fuel inside. In comparison to conventional jet fuels, LPG has potential benefits such as lower production cost, less environmental pollution, and greater resource accessibility.

Spec/Aircraft engine maintenance

The vast majority of aircraft turbo jet engines are designed to be easy to maintain in order to keep the aircraft operational for as long as possible. The main parts of an engine that need regular maintenance are:

• Fan

• Compressor

• Combustion chamber

• Turbine

• Nozzle

• Variable geometry

Maintenance is often just a case of cleaning, removing debris and ice, and applying lubrication when required. The precise schedule will depend on the type of aircraft that the engine is fitted into and its total flying hours.

More intensive engine maintenance requires the use of specialized equipment to support the engine while it is being worked on. Key procedures at this level include:

• Inspection

  Visual inspection of the outside of the engine for damage, loose, missing, or deformed parts, and operational signs from aircraft engine parts that the engine has not been working correctly. The inside of the engine is inspected using borescopes.

• Strip and clean

  Removing the external engine covers to clean the peripheral components and remove any insect or bird debris to help avoid engine ingestion issues.

• Parts replacement

  Some engine parts are subject to specified replacement intervals, usually after a specific number of flight hours.

• Repairs and Overhaul

  More complex engine repairs may be needed after inspections.

• Functional tests

  Specialized equipment is used to conduct functional tests on the engine's components, such as VGVs and the starter generator, while the engine is in a maintenance stand.

Engines that undergo regular maintenance at scheduled intervals quickly accumulate engine hours and 'fly away' time, making it more cost-effective to put them into service at some point later. If engines do not undergo regular maintenance, then their long-term operational prospects will be reduced, so it would be better to prolong their lives and make it economically worthwhile to send them for more detailed maintenance and repair. Regular maintenance will help sustain their salvage value.

Application Scenarios of turbo jet engines

The introduction of the turbojet engine brought about significant advancements in air travel, which continues to enhance numerous industries that depend on aircraft for various reasons daily.

• Aerospace:

  The turbo jet engine continues to play a critical role in diverse military applications. It serves as the primary propulsion system for various fighter jets, interceptors, bombers, and reconnaissance aircraft. The speedy acceleration of turbojet engines enables military aircraft to achieve high speeds rapidly, which is vital for air superiority, interception of incoming threats, and swift response to changing tactical situations.

• Commercial Aviation:

  The turbojet engine has greatly advanced the field of commercial aviation and is still an integral part of many passenger and cargo aircraft. Thanks to the swift acceleration and consistent propulsion of turbojet engines, airlines can cover expansive distances in a limited timeframe, thereby meeting the rising demand for global travel and transportation.

• Aviation R&D:

  Turbine jets are crucial in aviation research and development as they are used in experimental aircraft to test out new concepts and technologies connected with jet engine design and performance.

• Automotive Industry:

  Turbo jets also have an impact on the automotive sector. The concept of turbocharging, which is based on the functioning of turbo jet engines, has been extensively used to enhance the performance of internal combustion engines in automobiles.

• Space Exploration:

  Although turbojet engines don't directly contribute to space travel, their advancements definitely affected the progress of jet propulsion technology. These technologies may still be used as a foundation for developing new propulsion systems for future space exploration missions.

How to Choose a Turbo Jet Engine:

When selecting a turbo jet engine, several factors are critical to ensuring the right application.

• Purpose of Application:

  The primary objective for which the buyer intends to use the jet engine must be considered. If it is for a commercial aircraft, then engines that offer longevity, efficiency at cruising speeds, and proven reliability must be selected. Alternatively, if the application is for a military aircraft, emphasis should be on engines with high thrust output, rapid acceleration, and the ability to function at varying altitudes. For experimental aircraft, the focus may be on innovative designs or engines that incorporate new technologies.

• Thrust Requirements:

  The engine's required thrust must be determined. This is usually represented in pounds or kilonewtons. The intended aircraft weight and the mission profile must be considered to ensure the selected engine can provide the necessary thrust for takeoff, acceleration, and climb.

• Design Features:

  When selecting a jet engine, it's also crucial to consider its design characteristics. The buyer must consider the bypass ratio, which is the amount of air that bypasses the engine core compared to the amount that goes through it. High-bypass turbofans are more efficient and quieter, making them suitable for commercial airliners, while low-bypass turbofans are typically used in military jets for higher thrust and speed.

  Additionally, the buyer should research the engine's pressure ratio, which affects its efficiency and fuel consumption. Furthermore, the age and total flight hours of the engine must be considered, as older engines may require more frequent maintenance and overhauls.

• Engine Management System:

  Modern jet engines come equipped with an engine control digital electronic engine control system that manages various functions of the engine. Buyers must familiarize themselves with the specific EEC or FADEC system used in the engine they are considering. Different aircraft may use different types, which can affect maintenance and performance requirements.

• Supplier and Maintenance/Support Network:

  Buyers should consider the jet engine manufacturer and their global support network. It's important to select an engine for which a comprehensive maintenance and support network exists. This can simplify the maintenance process, ensure high-quality support, and help to maximize aircraft uptime. Additionally, the buyer should investigate the jet engine supplier's industry reputation and track record. Choosing a supplier with a proven history of reliable engines and excellent customer support can help minimize risk and ensure a successful operation.

Turbo jet engine FAQ

Q1: What is the difference between turbo engine and jet engine?

A1: A turbo engine uses the turbojet design where air enters the engine, is compressed, and pushed into the combustion chamber. A turbine then uses the temperature and pressure from the combusted air to rotate and power the compressor and the engine move the vehicle forward. A jet engine is a simple machine that creates thrust by pushing out a large volume of air from the rear. It mostly includes a compressor, combustion chamber, and turbine. The main difference is that the turbo engine uses a turbojet compressor to push out thrust, while the jet engine incorporates a simple machine that pushes out thrust.

Q2: What are some benefits of a turbo jet engine?

A2: Some benefits of the turbo jet engine include efficiency at high speeds and light construction. Many aircraft manufacturing companies can remove any extra weight because the engines have a simple and light construction. The aircraft easily reach and fly at high altitudes because the engines work well at high pressure and thin atmospheric levels.

Q3: What is the future of turbo jet engines?

A3: The future of turbo jet engines is likely to continue research into reducing greenhouse emissions from the combustion of fuel inside the engine. Some methods currently underway include replacing traditional aviation fuel with biofuel and improving engine designs to use less power during takeoff and more power during cruising at high altitudes.

Q4: Why are turbo jet engines not used in commercial aircraft?

A4: Turbo jets are less powerful and consume more fuel than turbo fan engines. Therefore, manufacturers mostly make these engines for use in military aircrafts only.