Experimental Investigation of a Radial Wave Engine Utilizing a Rotary Valved Pressure Gain Combustor

2020 ◽  
Author(s):  
Pejman Akbari ◽  
Grant M. Brady ◽  
Brian C. Sell ◽  
Marc D. Polanka
Keyword(s):  
Combustion Process ◽  
Axial Direction ◽  
Turbine Rotor ◽  
Rotary Valve ◽  
Radial Wave ◽  
Potential Benefits ◽  
Resident Time ◽  
Mass Flows ◽  
Initial Results ◽  
Engine Development

Abstract In this paper a deflagrative pressure gain combustor employing rotary valves is introduced that can reduce combustor length by allowing the combustion process to take place in the radial direction rather than in the axial direction with sufficient resident time. The engine is described in some detail with respect to geometry, components, and potential benefits. A demonstrator rig was designed, built, and tested for concept verification. A series of initial tests sweeping equivalence ratio from 0.4 to 0.8 using ethylene as fuel and mass flows from 75 g/s to 150 g/s is presented. The turbine rotor was driven to above 200 RPM with just four of the combustor passages operating. The initial results indicate the feasibility of the rotary valve radial engine concept and identified key challenges associated with the concept. Further studies are needed address existing challenges and to promote the engine development.

Experimental Investigation of a Radial Wave Engine Utilizing a Rotary Valved Pressure Gain Combustor

2020 ◽  
Author(s):  
Pejman Akbari ◽  
Grant M. Brady ◽  
Brian C. Sell ◽  
Marc D. Polanka
Keyword(s):  
Combustion Process ◽  
Axial Direction ◽  
Turbine Rotor ◽  
Rotary Valve ◽  
Radial Wave ◽  
Potential Benefits ◽  
Resident Time ◽  
Mass Flows ◽  
Initial Results ◽  
Engine Development

Abstract In this paper a deflagrative pressure gain combustor employing rotary valves is introduced that can reduce combustor length by allowing the combustion process to take place in the radial direction rather than in the axial direction with sufficient resident time. The engine is described in some detail with respect to geometry, components, and potential benefits. A demonstrator rig was designed, built, and tested for concept verification. A series of initial tests sweeping equivalence ratio from 0.4 to 0.8 using ethylene as fuel and mass flows from 75 g/s to 150 g/s is presented. The turbine rotor was driven to above 200 RPM with just four of the combustor passages operating. The initial results indicate the feasibility of the rotary valve radial engine concept and identified key challenges associated with the concept. Further studies are needed address existing challenges and to promote the engine development.

Aerodynamic Data for Two Variants of Root Turbine Blade Sections for a 54″ Turbine Rotor Blade

2014 ◽  
Author(s):  
David Šimurda ◽  
Martin Luxa ◽  
Pavel Šafařík ◽  
Jaroslav Synáč ◽  
Bartoloměj Rudas
Keyword(s):  
Limit Load ◽  
Axial Direction ◽  
Turbine Rotor ◽  
Rotor Blades ◽  
Angle Of Incidence ◽  
Flow Angle ◽  
Turbine Rotor Blade ◽  
Blade Cascade ◽  
The Difference ◽  
Kinetic Energy Loss

Aerodynamic investigations were performed on planar blade cascades representing two alternative root sections of rotor blades 54″ in length with straight fir-tree root. Each of the variants was designed for different number of blades in the rotor. This paper presents the results of measurements showing the dependency of the kinetic energy loss coefficient and the exit flow angle on the exit isoentropic Mach number and the angle of incidence. Images of the flow fields are also presented. The experimental data is analyzed to assess and document the difference between the two root section designs. Results show that requirement of straight fir tree root leading to high design incidence angles significantly limit operation range. Also in case of root sections with high exit Mach numbers a limit load conditions are an issue. In order to utilize available pressure drop blade cascade throat/pitch ratios should be kept as high as possible which favorites variant with lower number of blades and higher outlet metal angle (relative to axial direction).

Combustion in a high-speed rotary valve spark-ignition engine

2007 ◽  
Vol 221 (8) ◽  
pp. 971-990 ◽  
Author(s):  
P H P Chow ◽  
H C Watson ◽  
T Wallis
Keyword(s):  
High Speed ◽  
Combustion Process ◽  
Spark Ignition Engine ◽  
Combustion Model ◽  
Rotary Valve ◽  
Combustion Simulation ◽  
Parametric Effects ◽  
Sensitivity Studies ◽  
Valve Engine ◽  
Data Sensitivity

The current paper describes a study of combustion in the Bishop rotary valve engine by means of computation simulations. The combustion model was developed for this research at speeds up to 18 000 r/min and the results from the simulation were compared with experimental data. Sensitivity studies were performed in order to investigate the parametric effects on the combustion simulation of the engine. The major finding of this study was that convection of the flame kernels occurs and has a strong influence on the performance of the engine. The results indicated some insights as to how the combustion process of the engine can be improved.

Applying design to gender equality programming

2019 ◽  
Vol 2 (1) ◽  
Author(s):  
Isabella GADY ◽  
Nancy KHWEISS ◽  
María TARANCÓN
Keyword(s):  
Gender Equality ◽  
Social Innovation ◽  
Design Methods ◽  
Civil Society Organizations ◽  
Safe Space ◽  
Independent Evaluation ◽  
Potential Benefits ◽  
Specific Project ◽  
Initial Results

This case study explores the application of design methods and tools in women’s rights programming and feminist grant making - both areas that are, despite growing interest and evidence on potential benefits, still rather underexplored. In 2018, following its first independent evaluation and with the aim to increase its grantees‘ qualitative impact, the Fund for Gender Equality, a grant-making mechanism of the United Nations Entity for Gender Equality and Empowerment of Women, launched Re-Think. Experiment., an initiative exploring the potential for design to serve as a tool for innovation of programs. Through providing training in key principles of the design process and a safe space for experimentation, nine women-led civil society organizations operating in eleven countries have been equipped with tools and methodologies tailored to their needs to address specific project challenges. This case study introduces context, process and initial results of the initiative and discusses whether hopes for design to serve as a tool to foster innovation were met. Furthermore, it offers a critical reflection on its limitations, the need for contextualizing tools, and growing opportunities by marrying design methods with other social innovation disciplines.

Coupled Thermo-Mechanical Transient Stress Analysis of Functionally Graded Gas Turbine Rotor

2015 ◽  
Author(s):  
Dinesh Patil ◽  
D. Koteswara Rao ◽  
Tarapada Roy
Keyword(s):  
Shear Stress ◽  
Stress Analysis ◽  
Gas Turbine ◽  
Power Law ◽  
Shear Deformation Theory ◽  
Axial Direction ◽  
Turbine Rotor ◽  
Functionally Graded ◽  
Graded Materials ◽  
Turbine Shaft

This paper is concerned with the coupled thermo-mechanical stress analysis of functionally graded (FG) gas turbine rotor shaft system. Gas turbine shaft may expose in high temperature environments which demands to use functionally graded materials (FGMs). The aim of the present work is to study the stresses developed in the FG turbine shaft due to temperature variations and mechanical loading due to unbalance masses. For the present analysis aluminum oxide (Al2O3) and stainless steel (SUS304) are taken as shaft materials, power law gradation is used for the determination of FG material properties of the turbine shaft. Three nodded Timoshenko beam element with six degree of freedom (DOF) per node is considered for the finite element modelling of FG shaft. First order shear deformation theory (FSDT) is used with rotary inertia, strain and kinetic energy. Solution for governing equation of motion is obtained by the Hamilton principle. Complete MATLAB code has been developed for thermosmechanical stress analysis. Comparative study between steel shaft and FG shaft have been carried out. Normal stress (σxx) on plane perpendicular to axial direction, shear stress (τxr) on plane perpendicular to axial direction in radial direction and shear stress (τxθ) on plane perpendicular to axial direction in circumferential direction are obtained against time and along radius of shaft. Also these stresses are obtained for different parameters like power law indexes and speed of rotation of shaft.

Controlling Tip Leakage Flow Over a Shrouded Turbine Rotor Using an Air-Curtain

2009 ◽  
Author(s):  
Eric M. Curtis ◽  
John D. Denton ◽  
John P. Longley ◽  
Budimir Rosic
Keyword(s):  
Axial Direction ◽  
Turbine Rotor ◽  
Test Facility ◽  
Jet Flows ◽  
Leakage Flow ◽  
Tip Leakage Flow ◽  
Air Curtain ◽  
Tip Leakage ◽  
Turbine Efficiency ◽  
Air Turbine

This paper describes an experimental and computational investigation into the performance of an air-curtain seal used to control the leakage flow over the tip shroud of a turbine rotor. The results show that a seal of this type has the potential to reduce or eliminate shroud leakage whilst having a practical level of clearance between the stationary and moving components. The experimental measurements were undertaken using a single-stage low-speed air turbine equipped with a continuous circumferential nozzle in the casing to deliver an axisymmetric jet into the cavity over the rotor shroud. The jet was angled at 45° to the axial direction so that its momentum opposed the shroud leakage flow. In this arrangement the air-curtain was able to sustain the pressure difference between the inlet and outlet of the rotor blade row without any leakage. The test facility had comprehensive instrumentation for obtaining accurate measurements of turbine efficiency that were corrected for the externally supplied additional flow required for the air-curtain. Measurements were obtained for a range of jet flows and show the change in the turbine efficiency as the jet flow is increased. The measurements have been compared with calculations.

scholarly journals PREDIKSI KARAKTERISTIK TERMOFLUIDA PROSES PERPINDAHAN PANAS DI DALAM RUANG BAKAR INCINERATOR

2015 ◽  
Vol 16 (1) ◽  
pp. 43
Author(s):  
Veronica Indriati Sri Wardhani
Keyword(s):  
Heat Transfer ◽  
Process Simulation ◽  
Negative Impact ◽  
Variable Temperature ◽  
Outer Space ◽  
Combustion Process ◽  
Convection Heat Transfer ◽  
Axial Direction ◽  
Convection Heat ◽  
Convection Heat Transfer Coefficient

ABSTRAK PREDIKSI KARAKTERISTIK TERMOFLUIDA PROSES PERPINDAHAN PANAS DI DALAM RUANG BAKAR INCINERATOR. Penanganan limbah padat dengan proses pembakaran merupakan salah satu cara yang efektif sampai saat ini, instalasi incinerator masih menjadi perlatan pilihan yang dipergunakan untuk proses pembakaran. Namun penggunaan incinerator sebagai alat pembakaran sampah harus direncanakan dengan baik, karena efek yang dihasilkan adalah produk-produk destruktif yang justru bernilai negatif terhadap lingkungan. Mengingat proses pembakaran yang sangat kompleks di dalam incinerator, maka dilakukan simulasi dengan membuat suatu pemodelan menggunakan perangkat lunak compu-tational fluid dinamics (Fluent). Simulasi ini bertujuan untuk melihat karakteristik termo fluida yang terjadi di dalam ruang bakar incinerator meliputi variabel-variabel antara lain distribusi temperatur, sifat-sifat fisik fluida dan jenis aliran ( laminer atau turbulen ). Variabel-variabel tersebut akan mempengaruhi harga koefisien perpindahan panas konveksi (h). Perhitungan karakteristik termofluida yang meliputi panas yang mengalir (Q) dan koefisien perpindahan panas (h) pada tiga (3) titik pengukuran arah aksial diperoleh hasil koefisien perpindahan panas konveksi di ruang bagian dalam lebih besar 10 kali dari koefisien perpindahan panas konveksi di ruang bagian luar antara bata dalam dan bata luar. ABSTRACT THERMOFLUID characteristic prediction oF heat transfeR in the combustion chamber of incinerator. Handling of solid waste with the combustion process by installing the incinerator, is one effective way at present. However, the use of incinerators as a means of burning waste should be well planned, because of the resulted destructive products that have a negative impact to the environment. Considering the complexity process of combustion in the incinerator, the process simulation is done by using Computational fluid Dynamics software (Fluent). This simulation is proposed to obtain thermofluid characteristics such as variable temperature distribution, physical properties of the fluid and flow pattern (laminer or turbulent). These variables will affect the convection heat transfer coefficient (h). The Calculation characteristics of termofluida such as heat  flow (Q) and coefficient heat transfer (h) on three (3) points in axial direction obtained the coefficient heat transfer convection inner space is greater 10 times  than the coefficient heat transfer convection outer space  between the inner brick  and the outer brick.

scholarly journals Comparison between upwind and downwind designs of a 10 MW wind turbine rotor

2018 ◽  
Author(s):  
Pietro Bortolotti ◽  
Abinhav Kapila ◽  
Carlo L. Bottasso
Keyword(s):  
Wind Turbine ◽  
Energy Production ◽  
Turbine Rotor ◽  
Design Tool ◽  
Operating Conditions ◽  
Cost Of Energy ◽  
Potential Benefits ◽  
The Cost ◽  
Interesting Alternative ◽  
Wind Turbine Rotor

Abstract. The size of wind turbines has been steadily growing in the pursuit of a lower cost of energy by an increased wind capture. In this trend, the vast majority of wind turbine rotors has been designed based on the conventional three-bladed upwind concept. This paper aims at assessing the optimality of this configuration with respect to a three-bladed downwind design, with and without an actively controlled variable coning used to reduce the cantilever loading of the blades. A 10 MW wind turbine is used for the comparison of the various design solutions, which are obtained by an automated comprehensive aerostructural design tool. Results show that, for this turbine size, downwind rotors lead to blade mass and cost reductions of 6 % and 2 %, respectively, compared to equivalent upwind configurations. Due to a more favorable rotor attitude, the annual energy production of downwind rotors may also slightly increase in complex terrain conditions characterized by a wind upflow, leading to an overall reduction in the cost of energy. However, in more standard operating conditions, upwind rotors return the lowest cost of energy. Finally, active coning is effective in alleviating loads by reducing both blade mass and cost, but these potential benefits are negated by an increased system complexity and reduced energy production. In summary, a conventional design appears difficult to beat even at these turbine sizes, although a downwind non-aligned configuration might result in an interesting alternative.

scholarly journals Happy Or Not? Roots of Student Satisfaction in Class Sessions

2020 ◽  
Vol 6 (1) ◽  
pp. 11-17
Author(s):  
Matthew Metzgar
Keyword(s):  
Student Satisfaction ◽  
Consumer Satisfaction ◽  
Feedback System ◽  
Survey Tool ◽  
Time Commitment ◽  
Potential Benefits ◽  
Short Time ◽  
Smiley Face ◽  
Initial Results

AbstractBusinesses and organizations are turning to fast feedback devices that measure consumer satisfaction. These standalone devices often have four or five different smiley-face buttons that can quickly gauge consumer sentiment. These devices are becoming popular due to the short time commitment needed to provide feedback.This instructor has piloted the use of a smiley-face survey tool that is used at the end of each class session. Initial results suggest the role of the instructor may play a lesser role in student happiness for a given class. External factors, such as outside event or incoming GPA, appear to have a larger effect on class satisfaction. Data from classes and sample email exchanges will be presented. This type of fast feedback system has many potential benefits and low startup costs.

The Potential Conversion of the U.S. Great Lakes Steam Bulk Carriers to Liquefied Natural Gas Propulsion – Initial Report

2012 ◽  
Vol 28 (03) ◽  
pp. 97-111
Author(s):  
Michael G. Parsons ◽  
Patrick J. O'Hern ◽  
Samuel J. Denomy
Keyword(s):  
Natural Gas ◽  
Great Lakes ◽  
Liquefied Natural Gas ◽  
Air Emissions ◽  
Initial Report ◽  
Bulk Carriers ◽  
Potential Benefits ◽  
Lng Fuel ◽  
Marine Air ◽  
Initial Results

The feasibility and potential benefits of converting 10 remaining U.S. flag Great Lakes steamship bulk carriers to liquefied natural gas (LNG) propulsion using gas engines is investigated. This is the initial report of a study that began in November 2011. The evolving marine air emissions standards and the movement to LNG fuel in international nonLNG carriers are briefly reviewed. The case for the possible conversion of the remaining U.S. flag Great Lakes steamship bulk carriers to LNG fuel is outlined. Initial results of a conceptual design study on the conversion of the three AAA class vessels (SS Arthur M. Anderson, SS Cason J. Callaway, SS Philip R. Clarke), focusing primarily on operational and arrangement feasibility, is then presented.

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