Design of a Single Stage Variable Pitch Axial Fan

2017 ◽  
Author(s):  
Tommaso Bonanni ◽  
Alessandro Corsini ◽  
Giovanni Delibra ◽  
David Volponi ◽  
Anthony G. Sheard ◽  
...  
Keyword(s):  
High Efficiency ◽  
Fluid Dynamic ◽  
Single Stage ◽  
Department Of Energy ◽  
Development Effort ◽  
Blade Design ◽  
The European Union ◽  
Blade Profile ◽  
Axial Fan ◽  
Work Distribution

The European Union imposed minimum industrial fan efficiency levels in 2013 and then increased them in 2015. In the USA, the Department of Energy (DoE) is also developing regulations aimed at eliminating inefficient industrial fans from the market by 2023. A consequence of this regulatory activity is a need to apply design methods originally developed within the aerospace community to the design of high efficiency industrial fans. In this paper, we present a process used to design, numerically verify and experimentally test a high-pressure single-stage axial fan. The goal was a fan design capable of working over a range of blade angles in combination with a single fixed cambered plate stator. We present the process used when selecting blade airfoil sections and the vortex distribution along the blade span. The selected methodology is based on a coupling between the aerodynamic response of each blade profile and the chosen vortex distribution, creating a direct link between the load distribution and the aerodynamic capability of the blade profile section. This link is used to develop radial distributions of blade twist and chord for the selected blade profiles that result in the required radial work distribution. The design method has been enhanced through intermediate verifications using two different numerical methodologies. The methodologies are based on different approaches, in so doing providing confidence in the verification process. The final blade design has been analyzed using a three-dimensional computational fluid dynamic (CFD) code. Results of the CFD analysis indicate that performance of the final blade design is consistent with the design specifications. The paper concludes with a comparison between predicted and experimentally measured performance. The need is clarified for balance between computational and empirical approaches. When used together the development effort results in a lower cost and higher efficiency design than would have been possible using either approach in isolation.

scholarly journals Low-pressure reversible axial fan with straight profile blades and relatively high efficiency

2012 ◽  
Vol 16 (suppl. 2) ◽  
pp. 593-603 ◽  
Author(s):  
Zivan Spasic ◽  
Sasa Milanovic ◽  
Vanja Sustersic ◽  
Boban Nikolic
Keyword(s):  
Numerical Simulations ◽  
High Efficiency ◽  
Suction Side ◽  
Standard Test ◽  
Maximum Efficiency ◽  
Specific Work ◽  
Blade Profile ◽  
Operating Characteristics ◽  
Axial Fan ◽  
Increase Energy Efficiency

The paper presents the design and operating characteristics of a model of reversible axial fan with only one impeller, whose reversibility is achieved by changing the direction of rotation. The fan is designed for the purpose of providing alternating air circulation in wood dryers in order to reduce the consumption of electricity for the fan and increase energy efficiency of the entire dryer. To satisfy the reversibility of flow, the shape of the blade profile is symmetrical along the longitudinal and transversal axes of the profile. The fan is designed with equal specific work of all elementary stages, using the method of lift forces. The impeller blades have straight mean line profiles. The shape of the blade profile was adopted after the numerical simulations were carried out and high efficiency was achieved. Based on the calculation and conducted numerical simulations, a physical model of the fan was created and tested on a standard test rig, with air loading at the suction side of the fan. The operating characteristics are shown for different blade angles. The obtained maximum efficiency was around 0.65, which represents a rather high value for axial fans with straight profile blades.

scholarly journals CFD simulations to optimize the blade design of water wheels

2017 ◽  
Vol 10 (1) ◽  
pp. 27-32 ◽  
Author(s):  
Emanuele Quaranta ◽  
Roberto Revelli
Keyword(s):  
Fluid Dynamic ◽  
Experimental Tests ◽  
Blade Design ◽  
Average Increase ◽  
Blade Profile ◽  
Cfd Simulations ◽  
Circular Profile ◽  
Blade Shape ◽  
Low Head ◽  
Water Wheel

Abstract. At low head sites and at low discharges, water wheels can be considered among the most convenient hydropower converters to install. The aim of this work is to improve the performance of an existing breastshot water wheel by changing the blade shape using computational fluid dynamic (CFD) simulations. Three optimal profiles are investigated: the profile of the existing blades, a circular profile and an elliptical profile. The results are validated by performing experimental tests on the wheel with the existing profile. The numerical results show that the efficiency of breastshot wheels is affected by the blade profile. The average increase in efficiency using the new circular profile is about 4 % with respect to the profile of the existing blades.

scholarly journals Simulating NACA Equations Used in Optimizing Wind Turbine Blade Design: محاكاة معادلات NACA واستخدامها لتحسين تصميم شفرة العنفة الريحية

2021 ◽  
Vol 5 (4) ◽  
pp. 164-152
Author(s):  
Suzanne Ahmad Radwan Masri, Kheir Eddine Tarsha Kurdi, Ahmad Suzanne Ahmad Radwan Masri, Kheir Eddine Tarsha Kurdi, Ahmad
Keyword(s):  
High Efficiency ◽  
Operating Performance ◽  
Line Length ◽  
Blade Design ◽  
Blade Surface ◽  
Blade Profile ◽  
Optimal Operating ◽  
Turbine Blade Design ◽  
Twisting Angle ◽  
Great Energy

Aerodynamic scientists are interested in geometry definition and possible geometric shapes that would be useful in design. This paper illustrates a simulation of a NACA four digits airfoil blade profile using MATLAB. As airfoil design became more sophisticated, this basic approach has been modified to include additional variables, and suggestions for the chord line length at the root and at the end of the blade. as well as changes in the twisting angle of the blade and its thickness, this helps to reduce the weight of the blade significantly Simulating NACA equations is very useful in obtaining coordinates of airfoil curvature for the whole series of NACA four digits, which is very effective in optimizing blade design. In order to get an optimal operating performance and high efficiency for the airfoil, the blade surface must be smooth and does not suffer any discontinuities or undefined cases, which cause separation of the boundary layer during the airflow, and get as a result great energy losses. Therefore, the conditions for the continuity of the blade was extracted using mathematical analysis, so the air flow does not suffer any interruptions which reduce the efficiency. This enable us to determine the locations of the maximum thickness of the blade sections on the chord along the blade, in addition to specifying conditions for the chord line length at the root and at the end of the blade which keep the blade curvature continuous and doesn’t have any irregular points, which also facilities writing the necessary programs.

A New Practical Approach to the Design of Industrial Axial Fans: Part I — Tube-Axial Fans With Very Low Hub-to-Tip Ratio

2019 ◽  
Author(s):  
Massimo Masi ◽  
Andrea Lazzaretto
Keyword(s):  
Rotational Speed ◽  
High Efficiency ◽  
Design Method ◽  
Pressure Coefficient ◽  
Experimental Tests ◽  
Aerodynamic Load ◽  
Blade Design ◽  
Axial Fan ◽  
Flow Rate Coefficient ◽  
Axial Fans

Abstract This paper presents a simple but complete design method to obtain arbitrary vortex design tube-axial fans starting from fixed size and rotational speed. The method couples the preliminary design method previously suggested by the authors ago with an original revised version of well-known blade design methods taken from the literature. The aim of this work is to verify the effectiveness of the method in obtaining high efficiency industrial fans. To this end, the method has been applied to a 315mm rotor-only tube-axial fan having the same size and rotational speed, and a slightly higher flow rate coefficient, as another prototype previously designed by the authors, which was demonstrated experimentally to noticeably increase the pressure coefficient of an actual 560mm industrial fan. In contrast, no constraints are imposed on the hub-to-tip ratio and pressure coefficient. The new design features a hub-to-tip ratio equal to 0.28 and radially stacked blades with aerodynamic load distribution corresponding to a roughly constant swirl at rotor exit. The ISO-5801 experimental tests showed a fan efficiency equal to 0.68, which is 6% higher than that of the previous prototype. The pressure coefficient is lower, but still 12% higher than that of the benchmark 560mm industrial fan.

A New Practical Approach to the Design of Industrial Axial Fans: Tube-Axial Fans With Very Low Hub-to-Tip Ratio

2019 ◽  
Vol 141 (10) ◽  
Author(s):  
Massimo Masi ◽  
Andrea Lazzaretto
Keyword(s):  
Rotational Speed ◽  
High Efficiency ◽  
Design Method ◽  
Pressure Coefficient ◽  
Experimental Tests ◽  
Aerodynamic Load ◽  
Blade Design ◽  
Axial Fan ◽  
Flow Rate Coefficient ◽  
Axial Fans

This paper presents a simple but complete design method to obtain arbitrary vortex design tube-axial fans starting from fixed size and rotational speed. The method couples the preliminary design method previously suggested by the authors with an original revised version of well-known blade design methods taken from the literature. The aim of this work is to verify the effectiveness of the method in obtaining high-efficiency industrial fans. To this end, the method has been applied to a 315 mm rotor-only tube-axial fan having the same size and rotational speed, and a slightly higher flow rate coefficient, as another prototype previously designed by the authors, which was demonstrated experimentally to noticeably increase the pressure coefficient of an actual 560 mm industrial fan. In contrast, no constraints are imposed on the hub-to-tip ratio and pressure coefficient. The new design features a hub-to-tip ratio equal to 0.28 and radially stacked blades with aerodynamic load distribution corresponding to a roughly constant swirl at rotor exit. The ISO-5801 experimental tests showed fan efficiency equal to 0.68, which is 6% higher than that of the previous prototype. The pressure coefficient is lower, but still 12% higher than that of the benchmark 560 mm industrial fan.

scholarly journals Experimental Investigation and Comparison of the Thermal Performance of Additively and Conventionally Manufactured Heat Exchangers

Metals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 574
Author(s):  
Ana Vafadar ◽  
Ferdinando Guzzomi ◽  
Kevin Hayward
Keyword(s):  
Surface Roughness ◽  
Thermal Performance ◽  
Heat Exchangers ◽  
High Efficiency ◽  
Cooling System ◽  
Fluid Dynamic ◽  
Dynamic Performance ◽  
Experimental Studies ◽  
Manufacturing Method ◽  
Industrial Sectors

Air heat exchangers (HXs) are applicable in many industrial sectors because they offer a simple, reliable, and cost-effective cooling system. Additive manufacturing (AM) systems have significant potential in the construction of high-efficiency, lightweight HXs; however, HXs still mainly rely on conventional manufacturing (CM) systems such as milling, and brazing. This is due to the fact that little is known regarding the effects of AM on the performance of AM fabricated HXs. In this research, three air HXs comprising of a single fin fabricated from stainless steel 316 L using AM and CM methods—i.e., the HXs were fabricated by both direct metal printing and milling. To evaluate the fabricated HXs, microstructure images of the HXs were investigated, and the surface roughness of the samples was measured. Furthermore, an experimental test rig was designed and manufactured to conduct the experimental studies, and the thermal performance was investigated using four characteristics: heat transfer coefficient, Nusselt number, thermal fluid dynamic performance, and friction factor. The results showed that the manufacturing method has a considerable effect on the HX thermal performance. Furthermore, the surface roughness and distribution, and quantity of internal voids, which might be created during and after the printing process, affect the performance of HXs.

High Efficiency Combined Aggregate – Submerged Combustion Melter–Electric Furnace for Vitrification of High-Level Radioactive Wastes

2004 ◽  
Author(s):  
L. S. Pioro ◽  
I. L. Pioro
Keyword(s):  
Electric Furnace ◽  
High Efficiency ◽  
High Capacity ◽  
Main Idea ◽  
Melting Process ◽  
Radioactive Wastes ◽  
Single Stage ◽  
Interface Surface ◽  
High Level ◽  
Submerged Combustion

It is well known that high-level radioactive wastes (HLRAW) are usually vitrified inside electric furnaces. Disadvantages of electric furnaces are their low melting capacity and restrictions on charge preparation. Therefore, a new concept for a high efficiency combined aggregate – submerged combustion melter (SCM)–electric furnace was developed for vitrification of HLRAW. The main idea of this concept is to use the SCM as the primary high-capacity melting unit with direct melt drainage into an electric furnace. The SCM employs a single-stage method for vitrification of HLRAW. The method includes concentration (evaporation), calcination, and vitrification of HLRAW in a single-stage process inside a melting chamber of the SCM. Specific to the melting process is the use of a gas-air or gas-oxygen-air mixture with direct combustion inside a melt. Located inside the melt are high-temperature zones with increased reactivity of the gas phase, the existence of a developed interface surface, and intensive mixing, leading to intensification of the charge melting and vitrification process. The electric furnace clarifies molten glass, thus preparing the high-quality melt for subsequent melt pouring into containers for final storage.

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