Integrated Design and Analysis of Turbofan Engines

High bypass ratio (BPR) fans are of heightened interest in the area of civil air vehicle propulsion. It increases the air inhaling and improves both the thrust and the propulsive efficiency. The specific fuel consumption is also reduced in today’s turbofan engines.

The inlet fan designs and optimizations are very important as the fan can be subjected to different inlet conditions. As a matter of fact, a modern high bypass fan system provides over 85% of the engine’s net thrust. Hence, a well-designed bypass fan system is crucial for the overall propulsion characteristics of a turbofan engine. A tool which can perform both inverse tasks and direct tasks on bypass fan system is a necessity for turbofan design.

Figure 1 - Turbofan
Figure 1 Meridional Section of the Turbofan Engine
AxSTREAM ® Streamline Solver

The AxSTREAM® streamline solver is a throughflow solver, the specificity of the outcome one should expect from this solver is up the meridional flow field. Hence, when we develop the model, we shall take Acarer and Özkol’s work [2016] as a reference example. Read More

An Overview of Axial Fans

Axial fans have become indispensable in everyday applications starting from ceiling fans to industrial applications and aerospace fans.  The fan has become a part of every application where ventilation and cooling is required, like in a condenser, radiator, electronics etc., and they are available in the wide range of sizes from few millimeters to several meters. Fans generate pressure to move air/gases against the resistance caused by ducts, dampers, or other components in a fan system. Axial-flow fans are better suited for low-resistance, high-flow applications and can have widely varied operating characteristics depending on blade width and shape, number of blades, and tip speed.

Fan Types

The major types of axial flow fans are: propeller, tube axial, and vane axial.

  • – Propellers usually run at low speeds and handle large volumes of gas at low pressure. Often used as exhaust fans these have an efficiency of around 50% or less.
  • – Tube-axial fans turn faster than propeller fans, enabling operation under high-pressures 2500 – 4000 Pa with an efficiency of up to 65%.
  • – Vane-axial fans have guide vanes that improve the efficiency and operate at pressures up to 5000 Pa. Efficiency is up to 85%.
Types of Fans
Figure 1 Different Types of Axial Fans
Aerodynamic Design of an Axial Fan

The aerodynamic design of an axial fan depends on its applications. For example, axial fans for industrial cooling applications operate at low speeds and require simple profile shapes. When it comes to aircraft applications however, the fan must operate at very high speeds, and the aerodynamic design requirements become significantly different from more traditional fan designs. Read More

Redesigning Anakin Skywalker’s Podracer

Ever since circa 100 BBY, Podracing in its modern version has drawn crowds from far far away to watch pilots compete in races like the Boonta Eve Classic which made Anakin Skywalker famous and won him his freedom. By beating Sebulba, the Dug, and the other Podracers, Anakin became the first human to be successful at this very dangerous sport. The Force helped him in his victory by sharpening his reflexes, but his repulsorcraft was also superior due to its size and the modifications made to its twin Radon-Ulzer 620C engines, especially the fuel atomizer and distribution system with its multiple igniters which makes them run similarly to afterburners seen on some military planes on Earth.

Figure 1 Pilots and their Repulsorcrafts at the Start of the Boonta Even Classic Race on Tatooine
Figure 1 Pilots and their Repulsorcrafts at the Start of the Boonta Eve Classic Race on Tatooine

Let’s take a deeper look at what repulsorcrafts are and how we can help Anakin redesign his to gain an even better advantage against the competition, provided that Watto has the correct equipment in his junk yard. Read More

Aerospace Industry and Propulsion Advancements – A Teaser for the Farnborough International Airshow

Due to technological advancements in the aerospace industry, air transportation has become the primary means of travelling. This begs the question of “what are the key factors that could push the industry to the next level and allow for higher performance, low cost and low carbon emission flights?”

Airplane - Aerospace

For a low carbon aviation to be achieved, a lot of effort is currently put on the aircraft-propulsion integration. Low-pressure-ratio fans are one of the concepts that is being studied in this regard. The lower the pressure across the propulsive element the more the exhaust velocities will decrease and therefore the higher the propulsive efficiency will be. However, a constant level of thrust would require an increase of the fan area, which could lead to an increase of the total weight of the configuration and ultimately cancel the efficiency benefits of the concept.
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Upcoming Webinar: Design and Optimization of Axial and Mixed Flow Fans for High Efficiency and Low Noise

Thursday, May 18 | 10:00 – 11:00 AM EST

Axial Fan CAD Image
Registration is now open for our May webinar demonstrating best practices for the development of competitive, high efficiency, and low noise axial and mixed flow fans for different aerodynamic loadings.

Axial and mixed flow fans have been in high demand for a number of years. The application of these machines span many different industries including HVAC, automotive, appliance, military equipment, and much more. Like many other types of turbomachinery, changing industry standards and market trends have resulted in fierce rivalry to compete on lifespan, efficiency, environmental and user friendliness, and overall quality. With this in mind, it goes without saying that companies are looking for tools needed to develop highly efficient equipment while minimizing noise as quiet fans are typically more desirable which results in higher demand and marketability.

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Rotating Equipment Specialist in the Oil and Gas Industry – A Turbomachinery Professional

Turbomachinery is a core subject in many engineering curriculums. However, many graduates joining the oil and gas industry are designated as rotating equipment engineers. Though turbomachinery and rotating equipment are used synonymously, all turbomachinery are rotating equipment but not vice versa. Turbinis in Latin implies spin or whirl, and a natural question that arises is – what are the factors that differentiate turbomachinery?  In a general sense the term, “rotating” covers  the majority equipment used in the industry be it in the upstream, mid-stream or the downstream segment. Yet top rotating equipment specialist in the industry are seen spending their prime time or often being associated with certain unique and specific types of critical rotating machines – the turbomachines.Oil and Gas

In a classical sense, turbomachines are devices in which energy is added into or taken out from a continuously flowing fluid by the dynamic action of one or more moving blade rows. By this definition propellers, wind turbines and unshrouded fans are also turbomachines but they require a separate treatment. The subject of fluid mechanics, aerodynamics, thermodynamics and material mechanics of turbomachinery when limited to machines enclosed by a closely fitting casing or shroud through which a measurable quantity of fluid passing in unit time makes the practical linkage to rotating equipment – those which absorb power to increase the fluid pressure or head (fans, compressors and pumps) and those that produce power by expanding fluid to a lower pressure or head (hydraulic, steam and gas turbines). Further classification into axial, radial and mixed type (based on flow contour), and impulse & reaction (based on principle of energy transfer) is common. It is the large range of service requirement that leads to different type of pump (or compressor) and turbine in service.

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Understanding the Characteristics of Varying Centrifugal Blower Designs

Many people speculate about the confusion on what is considered a compressor, a blower, or simply a fan.  In essence, each of these turbo-machines achieve a pressure rise by adding velocity to a continuous flow of fluid.  The distinctions between fans, blowers, and compressors are quite simply defined by one parameter, the specific pressure ratio.  Each machine type, however, utilizes a number of different design techniques specific to lower and higher-pressure applications.  As per the American Society of Mechanical Engineers (ASME), the specific pressure is defined as the ratio of the discharge pressure over the suction pressure (or inlet pressure).  The table shown below defines the range at which fans, blowers, and compressors are categorized.
table

Similarities between the design of fans and blowers occur near the lower end of a blower’s range.  As well, many design parallels exist between high-pressure blowers and compressors.  For the article, we will be investigating the different design characteristics of centrifugal blowers. Blower selection depends on a number of factors including operating range, efficiency, space limitations, and material handled.   Figure 1 shows a number of different impeller blade designs that are available for centrifugal blowers.

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