Pablo Mora is a doctoral candidate in the Department of Aerospace Engineering at the University of Cincinnati. His research focuses on reducing jet noise levels through experimental and computational studies of heated supersonic jets. He utilizes a heated jet noise facility with flow and acoustic measurement capabilities. Recent work involves Particle Image Velocimetry and Large Eddy Simulation studies of turbulence properties in a high-temperature supersonic jet, as well as studies of noise reduction methods like chevrons. The goal is to better understand noise generation mechanisms in heated jets and develop noise mitigation strategies to protect those exposed to high-intensity jet noise.
The project involves studying flow properties and quantification of acoustics analysis through identification of sources in the flow. A comparison of various nozzle pressure ratios and temperature ratios was conducted to study their effect on flow properties.
Ultrasonic testing methods:
Introduction, Principle of operation, Piezoelectricity. Ultrasonic probes, CRO techniques,advantages,
Limitation & typical applications. Applications in inspection of castings, forgings,Extruded steel parts,
bars, pipes, rails and dimensions measurements. Case Study –Ultrasonography of human body.
A study on effect of bowing on a scans using pulse echo ultrasonic technique eSAT Journals
Abstract This paper deals with the study of A Scans obtained from sub assembly head top used in a Prototype Fast Breeder Reactor. A sub-assembly head top is the specimen used to determine the effect of bowing on A Scans. The condition of bowing has been simulated. The A Scans are obtained under normal conditions of the ring and also under simulated bowing conditions. The envelope of the A Scans under both the conditions have been compared. It is found that the two edges of the ring are clearly indicated through the A Scan. Under normal conditions, the two edges have a slight difference in the depth. This is due to the constructional feature of the object. But under simulated conditions, the two edges are obtained at two different depths, of magnitude higher than the normal conditions. The shift in the A Scans is clearly seen It is observed that greater the tilt given for simulated bowing, larger is the shift in the depth of the two edges of the ring. Index Terms: Ultrasonic, Pulse Echo, Bowing, A Scans
The project involves studying flow properties and quantification of acoustics analysis through identification of sources in the flow. A comparison of various nozzle pressure ratios and temperature ratios was conducted to study their effect on flow properties.
Ultrasonic testing methods:
Introduction, Principle of operation, Piezoelectricity. Ultrasonic probes, CRO techniques,advantages,
Limitation & typical applications. Applications in inspection of castings, forgings,Extruded steel parts,
bars, pipes, rails and dimensions measurements. Case Study –Ultrasonography of human body.
A study on effect of bowing on a scans using pulse echo ultrasonic technique eSAT Journals
Abstract This paper deals with the study of A Scans obtained from sub assembly head top used in a Prototype Fast Breeder Reactor. A sub-assembly head top is the specimen used to determine the effect of bowing on A Scans. The condition of bowing has been simulated. The A Scans are obtained under normal conditions of the ring and also under simulated bowing conditions. The envelope of the A Scans under both the conditions have been compared. It is found that the two edges of the ring are clearly indicated through the A Scan. Under normal conditions, the two edges have a slight difference in the depth. This is due to the constructional feature of the object. But under simulated conditions, the two edges are obtained at two different depths, of magnitude higher than the normal conditions. The shift in the A Scans is clearly seen It is observed that greater the tilt given for simulated bowing, larger is the shift in the depth of the two edges of the ring. Index Terms: Ultrasonic, Pulse Echo, Bowing, A Scans
DON'T MISS THIS DEAL!!!
Get the Ultrasonic Testing level 1 training for only $5 and save 83%. use this link to get the discount
https://www.udemy.com/ultrasonic-testing/?couponCode=PROEmailPromo
The course provides you with Level 1 training in the fundamentals of Ultrasonic Testing methods. It will introduce you to the basic concepts and principles and includes hands-on training using Ultrasonic Testing
equipment settings and functions.The Ultrasonic theories presented will provide the knowledge of Ultrasonic Testing required and enable you to work with individuals qualified and certified to gain needed experience for qualification as Level 1. While the practicle manipulations will give you the essential steps that you will need to calibrate the ultrasonic testing equipment, perform the inspection, collect and interpret the data.This course consists of two handbooks: The first handbook made by the instructor is the official of the training. It covers all the topics presented through the 39 lectures. While the second one (offered as bonus) is the official one of the TWI (International Institute of Welding) training.In addition to that, the course includes 39 lectures alternating between the different lecture types, with regular quizzes and exams to enable you to check that your are following the topics covered.
Acoustic Emission (AE) refers to the generation of transient elastic waves produced by a sudden redistribution of stress in a material. When a structure is subjected to an external stimulus (change in pressure, load, or temperature), localized sources trigger the release of energy, in the form of stress waves, which propagate to the surface and are recorded by sensors. With the right equipment and setup, motions on the order of picometers (10 -12 m) can be identified. Sources of AE vary from natural events like earthquakes and rockbursts to the initiation and growth of cracks, slip and dislocation movements, melting, twinning, and phase transformations in metals. In composites, matrix cracking and fiber breakage and debonding contribute to acoustic emissions. AE’s have also been measured and recorded in polymers, wood, and concrete, among other materials.
1.1 The aim of the experiment
The aim of the experiment is to test the usefulness of the ultrasonic waves, by passing them through different
solids one can find out a lot of physical properties like young’s modulus , defects, Poisson ratio, Velocity of
sound in respective material this is due to the response of the received ultrasonic waves.
1.2 Theory of experiment
Ultrasonic testing (UT) is a family of non-destructive testing (NDT) techniques based on the propagation of ultrasonic waves in the object or material tested. In most common UT applications, very short ultrasonic pulse-waves with center frequencies ranging from 0.1-15 MHz, and occasionally up to 50 MHz, are transmitted into materials to detect internal flaws or to characterize materials. A common example is ultrasonic thickness measurement, which tests the thickness of the test object, for example, to monitor pipework corrosion.
Ultrasonic testing is often performed on steel and other metals and alloys, though it can also be used on concrete, wood and composites, albeit with less resolution. It is used in many industries including steel and aluminium construction, metallurgy, manufacturing, aerospace, automotive and other transportation sectors.
M4 ndt me 367 introductiontoultrasonictestingHareesh K
This presentation explains the basics of ultrasonic inspection.Different practical aspects and various types of techniques are explained detail in this module.
DON'T MISS THIS DEAL!!!
Get the Ultrasonic Testing level 1 training for only $5 and save 83%. use this link to get the discount
https://www.udemy.com/ultrasonic-testing/?couponCode=PROEmailPromo
The course provides you with Level 1 training in the fundamentals of Ultrasonic Testing methods. It will introduce you to the basic concepts and principles and includes hands-on training using Ultrasonic Testing
equipment settings and functions.The Ultrasonic theories presented will provide the knowledge of Ultrasonic Testing required and enable you to work with individuals qualified and certified to gain needed experience for qualification as Level 1. While the practicle manipulations will give you the essential steps that you will need to calibrate the ultrasonic testing equipment, perform the inspection, collect and interpret the data.This course consists of two handbooks: The first handbook made by the instructor is the official of the training. It covers all the topics presented through the 39 lectures. While the second one (offered as bonus) is the official one of the TWI (International Institute of Welding) training.In addition to that, the course includes 39 lectures alternating between the different lecture types, with regular quizzes and exams to enable you to check that your are following the topics covered.
Acoustic Emission (AE) refers to the generation of transient elastic waves produced by a sudden redistribution of stress in a material. When a structure is subjected to an external stimulus (change in pressure, load, or temperature), localized sources trigger the release of energy, in the form of stress waves, which propagate to the surface and are recorded by sensors. With the right equipment and setup, motions on the order of picometers (10 -12 m) can be identified. Sources of AE vary from natural events like earthquakes and rockbursts to the initiation and growth of cracks, slip and dislocation movements, melting, twinning, and phase transformations in metals. In composites, matrix cracking and fiber breakage and debonding contribute to acoustic emissions. AE’s have also been measured and recorded in polymers, wood, and concrete, among other materials.
1.1 The aim of the experiment
The aim of the experiment is to test the usefulness of the ultrasonic waves, by passing them through different
solids one can find out a lot of physical properties like young’s modulus , defects, Poisson ratio, Velocity of
sound in respective material this is due to the response of the received ultrasonic waves.
1.2 Theory of experiment
Ultrasonic testing (UT) is a family of non-destructive testing (NDT) techniques based on the propagation of ultrasonic waves in the object or material tested. In most common UT applications, very short ultrasonic pulse-waves with center frequencies ranging from 0.1-15 MHz, and occasionally up to 50 MHz, are transmitted into materials to detect internal flaws or to characterize materials. A common example is ultrasonic thickness measurement, which tests the thickness of the test object, for example, to monitor pipework corrosion.
Ultrasonic testing is often performed on steel and other metals and alloys, though it can also be used on concrete, wood and composites, albeit with less resolution. It is used in many industries including steel and aluminium construction, metallurgy, manufacturing, aerospace, automotive and other transportation sectors.
M4 ndt me 367 introductiontoultrasonictestingHareesh K
This presentation explains the basics of ultrasonic inspection.Different practical aspects and various types of techniques are explained detail in this module.
Air Flow Across Cavities (Aircraft Industry) - Gan Chun ChetGan Chun Chet
Rectangular Cavity L/D = 1, 1.2, 2 and 3, low speed (takeoff and landing speed), as well as Circular Cavity at MACH 2.3, high speed.
Experimental study.
Acoustics and vibrations of marine renewables- Mark-Paul Buckinghamrebeccalynam
Xi Engineering Consultants will share their expertise in this field and discuss their latest research on the noise effects of operational offshore wind turbines on marine species that commonly occur in the Irish Sea.
Noise Reduction Modelling Study for Aircraft Cavity - Chun C GanGan Chun Chet
Modelling (Aircraft) Air Flow Across Rectangular Cavity, reduction in noise amplitude, postulating higher boundary layer frequency (efficient noise to signal ratio)
Design verification of offshore wind turbines for foundation optimization and...Pieter Jan Jordaens
OWI-Lab develops short- and long-term monitoring solutions for offshore wind turbines. The motivation is gaining the insights that are crucial to minimize construction and installations costs of future offshore wind farms and to extend the life time of existing structures and
reduce their operation and maintenance costs. The main goal of this poster is to share the results of an extensive design verification camping. The results will allow improving current standards. Ultimately, reducing the cost of offshore wind energy.
In design verification the resonance frequencies of
the fundamental tower modes are identified using a
mobile measurement system and state-of the art
operational modal analysis (OMA) techniques. The obtained frequencies are compared with the as designed
values.
Conclusion:
Results indicate a general underestimation of the soil
stiffness. The first resonance frequency is between 5%
and 10% higher then designed. The second resonance
frequency is between 15% and 40% higher then designed. It was found that the relative difference with as designed values increased with water depth and was independent of the monopile length. Moreover it was found that the second bending mode frequencies coincided with the 6P blade passing frequencies. This can result in higher loads and therefore reduced lifetime or increased O&M costs.
Sonics and ultrasonics in endodontics /certified fixed orthodontic courses b...Indian dental academy
Welcome to Indian Dental Academy
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and offering a wide range of dental certified courses in different formats.
Indian dental academy has a unique training program & curriculum that provides students with exceptional clinical skills and enabling them to return to their office with high level confidence and start treating patients
State of the art comprehensive training-Faculty of world wide repute &Very affordable.
international workshop accelerator based neutron sources for medical industrial and scientific applications torino eurosea international workshop accelerator based neutron sources for medical industrial and scientific applications torino eurosea
Ultrasound color Doppler imaging has been routinely used for the diagnosis of cardiovascular diseases, enabling real-time flow visualization through the Doppler effect. Yet, its inability to provide true flow velocity vectors due to its one-dimensional detection limits its efficacy. To overcome this limitation, various VFI schemes, including multi-angle beams, speckle tracking, and transverse oscillation, have been explored, with some already available commercially. However, many of these methods still rely on autocorrelation, which poses inherent issues such as underestimation, aliasing, and the need for large ensemble sizes. Conversely, speckle-tracking-based VFI enables lateral velocity estimation but suffers from significantly lower accuracy compared to axial velocity measurements.
To address these challenges, we have presented a speckle-tracking-based VFI approach utilizing multi-angle ultrafast plane wave imaging. Our approach involves estimating axial velocity components projected onto individual steered plane waves, which are then combined to derive the velocity vector. Additionally, we've introduced a VFI visualization technique with high spatial and temporal resolutions capable of tracking flow particle trajectories.
Simulation and flow phantom experiments demonstrate that the proposed VFI method outperforms both speckle-tracking-based VFI and autocorrelation VFI counterparts by at least a factor of three. Furthermore, in vivo measurements on carotid arteries using the Prodigy ultrasound scanner demonstrate the effectiveness of our approach compared to existing methods, providing a more robust imaging tool for hemodynamic studies.
Learning objectives:
- Understand fundamental limitations of color Doppler imaging.
- Understand principles behind advanced vector flow imaging techniques.
- Familiarize with the ultrasound speckle tracking technique and its implications in flow imaging.
- Explore experiments conducted using multi-angle plane wave ultrafast imaging, specifically utilizing the pulse-sequence mode on a 128-channel ultrasound research platform.
About
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Technical Specifications
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
Key Features
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface
• Compatible with MAFI CCR system
• Copatiable with IDM8000 CCR
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
Application
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
CFD Simulation of By-pass Flow in a HRSG module by R&R Consult.pptxR&R Consult
CFD analysis is incredibly effective at solving mysteries and improving the performance of complex systems!
Here's a great example: At a large natural gas-fired power plant, where they use waste heat to generate steam and energy, they were puzzled that their boiler wasn't producing as much steam as expected.
R&R and Tetra Engineering Group Inc. were asked to solve the issue with reduced steam production.
An inspection had shown that a significant amount of hot flue gas was bypassing the boiler tubes, where the heat was supposed to be transferred.
R&R Consult conducted a CFD analysis, which revealed that 6.3% of the flue gas was bypassing the boiler tubes without transferring heat. The analysis also showed that the flue gas was instead being directed along the sides of the boiler and between the modules that were supposed to capture the heat. This was the cause of the reduced performance.
Based on our results, Tetra Engineering installed covering plates to reduce the bypass flow. This improved the boiler's performance and increased electricity production.
It is always satisfying when we can help solve complex challenges like this. Do your systems also need a check-up or optimization? Give us a call!
Work done in cooperation with James Malloy and David Moelling from Tetra Engineering.
More examples of our work https://www.r-r-consult.dk/en/cases-en/
Final project report on grocery store management system..pdfKamal Acharya
In today’s fast-changing business environment, it’s extremely important to be able to respond to client needs in the most effective and timely manner. If your customers wish to see your business online and have instant access to your products or services.
Online Grocery Store is an e-commerce website, which retails various grocery products. This project allows viewing various products available enables registered users to purchase desired products instantly using Paytm, UPI payment processor (Instant Pay) and also can place order by using Cash on Delivery (Pay Later) option. This project provides an easy access to Administrators and Managers to view orders placed using Pay Later and Instant Pay options.
In order to develop an e-commerce website, a number of Technologies must be studied and understood. These include multi-tiered architecture, server and client-side scripting techniques, implementation technologies, programming language (such as PHP, HTML, CSS, JavaScript) and MySQL relational databases. This is a project with the objective to develop a basic website where a consumer is provided with a shopping cart website and also to know about the technologies used to develop such a website.
This document will discuss each of the underlying technologies to create and implement an e- commerce website.
Hybrid optimization of pumped hydro system and solar- Engr. Abdul-Azeez.pdffxintegritypublishin
Advancements in technology unveil a myriad of electrical and electronic breakthroughs geared towards efficiently harnessing limited resources to meet human energy demands. The optimization of hybrid solar PV panels and pumped hydro energy supply systems plays a pivotal role in utilizing natural resources effectively. This initiative not only benefits humanity but also fosters environmental sustainability. The study investigated the design optimization of these hybrid systems, focusing on understanding solar radiation patterns, identifying geographical influences on solar radiation, formulating a mathematical model for system optimization, and determining the optimal configuration of PV panels and pumped hydro storage. Through a comparative analysis approach and eight weeks of data collection, the study addressed key research questions related to solar radiation patterns and optimal system design. The findings highlighted regions with heightened solar radiation levels, showcasing substantial potential for power generation and emphasizing the system's efficiency. Optimizing system design significantly boosted power generation, promoted renewable energy utilization, and enhanced energy storage capacity. The study underscored the benefits of optimizing hybrid solar PV panels and pumped hydro energy supply systems for sustainable energy usage. Optimizing the design of solar PV panels and pumped hydro energy supply systems as examined across diverse climatic conditions in a developing country, not only enhances power generation but also improves the integration of renewable energy sources and boosts energy storage capacities, particularly beneficial for less economically prosperous regions. Additionally, the study provides valuable insights for advancing energy research in economically viable areas. Recommendations included conducting site-specific assessments, utilizing advanced modeling tools, implementing regular maintenance protocols, and enhancing communication among system components.
Democratizing Fuzzing at Scale by Abhishek Aryaabh.arya
Presented at NUS: Fuzzing and Software Security Summer School 2024
This keynote talks about the democratization of fuzzing at scale, highlighting the collaboration between open source communities, academia, and industry to advance the field of fuzzing. It delves into the history of fuzzing, the development of scalable fuzzing platforms, and the empowerment of community-driven research. The talk will further discuss recent advancements leveraging AI/ML and offer insights into the future evolution of the fuzzing landscape.
Saudi Arabia stands as a titan in the global energy landscape, renowned for its abundant oil and gas resources. It's the largest exporter of petroleum and holds some of the world's most significant reserves. Let's delve into the top 10 oil and gas projects shaping Saudi Arabia's energy future in 2024.
TECHNICAL TRAINING MANUAL GENERAL FAMILIARIZATION COURSEDuvanRamosGarzon1
AIRCRAFT GENERAL
The Single Aisle is the most advanced family aircraft in service today, with fly-by-wire flight controls.
The A318, A319, A320 and A321 are twin-engine subsonic medium range aircraft.
The family offers a choice of engines
Immunizing Image Classifiers Against Localized Adversary Attacksgerogepatton
This paper addresses the vulnerability of deep learning models, particularly convolutional neural networks
(CNN)s, to adversarial attacks and presents a proactive training technique designed to counter them. We
introduce a novel volumization algorithm, which transforms 2D images into 3D volumetric representations.
When combined with 3D convolution and deep curriculum learning optimization (CLO), itsignificantly improves
the immunity of models against localized universal attacks by up to 40%. We evaluate our proposed approach
using contemporary CNN architectures and the modified Canadian Institute for Advanced Research (CIFAR-10
and CIFAR-100) and ImageNet Large Scale Visual Recognition Challenge (ILSVRC12) datasets, showcasing
accuracy improvements over previous techniques. The results indicate that the combination of the volumetric
input and curriculum learning holds significant promise for mitigating adversarial attacks without necessitating
adversary training.
COLLEGE BUS MANAGEMENT SYSTEM PROJECT REPORT.pdfKamal Acharya
The College Bus Management system is completely developed by Visual Basic .NET Version. The application is connect with most secured database language MS SQL Server. The application is develop by using best combination of front-end and back-end languages. The application is totally design like flat user interface. This flat user interface is more attractive user interface in 2017. The application is gives more important to the system functionality. The application is to manage the student’s details, driver’s details, bus details, bus route details, bus fees details and more. The application has only one unit for admin. The admin can manage the entire application. The admin can login into the application by using username and password of the admin. The application is develop for big and small colleges. It is more user friendly for non-computer person. Even they can easily learn how to manage the application within hours. The application is more secure by the admin. The system will give an effective output for the VB.Net and SQL Server given as input to the system. The compiled java program given as input to the system, after scanning the program will generate different reports. The application generates the report for users. The admin can view and download the report of the data. The application deliver the excel format reports. Because, excel formatted reports is very easy to understand the income and expense of the college bus. This application is mainly develop for windows operating system users. In 2017, 73% of people enterprises are using windows operating system. So the application will easily install for all the windows operating system users. The application-developed size is very low. The application consumes very low space in disk. Therefore, the user can allocate very minimum local disk space for this application.
Industrial Training at Shahjalal Fertilizer Company Limited (SFCL)MdTanvirMahtab2
This presentation is about the working procedure of Shahjalal Fertilizer Company Limited (SFCL). A Govt. owned Company of Bangladesh Chemical Industries Corporation under Ministry of Industries.
1. Doctoral Research Overview
Pablo Mora
University of Cincinnati
Department of Aerospace Engineering
Cincinnati, Ohio, 45221
Acknowledgment:
This research has been sponsored by the Office
of Naval Research (ONR) through the Jet Noise
Reduction (JNR) Project under the Noise
Induced Hearing Loss (NIHL) program, as well
as the NRL 6.1 Computational Physics Task
Area.
Heated Jet Noise Facility
3. Reduce noise levels for those exposed to high-intensity jet noise
160 90 100 110 120 130 140 150 160
110
115
120
125
130
135
140
145
OASPL
90 100 110 120 130 140 150 160
110
115
120
125
130
135
140
145
OASPL
Increasing
Temperature
Heated Jet Noise Research
Motivation
Noise increases dramatically
with jet temperature
Uc
a∞
Φ
Mach wave radiation and
Crackle noise waves
Additional noise components in high-
temperature high-speed jets
https://acoustics.byu.edu/research/beamforming-understand-military-jet-noise
Overall Sound Pressure Level [dB]
4. Heated Jet Noise Facility
Capabilities
Acoustic Measurements
• Free-field and surface microphones
Flow Measurements
• PIV & LDV (velocity and turbulence)
• Pressure transducers and thermocouples
• Supersonic pitot tube
Flow Visualization
• High-speed shadowgraph & schlieren
Near-field Microphone
Array on Traverse System
Aluminum oxide particle seeder
for Laser Doppler Velocimetry
• Two supply air tanks with 22,000lbs capacity at
1800psig are filled by a 360SCFM compressor
• Jet air can be heated up to 1200oF by inline
72kW and 96kW Osram Sylvania electric heaters
Concentric far-field
microphone arrays
LDV optics on a 3-axis Traverse System
5. Nozzle Geometries
Design Mach Number = 1.5
Rectangular Nozzle
Nozzle Geometry
Equivalent Dexit [in] AR Height [in] Width [in]
0.813 2:1 0.51 1.02
Circular Nozzles
Dexit [inches]
Base Chev M.O.C.
0.542
0.813 0.813 0.813
1.085
Baseline Chevrons Contoured
Method of Characteristics
Scale Study
6. Jet Over a Flat Surface
Reflections and Jet-Surface Interaction Noise
http://www.nasa.gov/larc/helicopter-drop-test-a-smashing-success
http://avioners.net/wp-content/uploads/blogger/-4CzoQlxE3ls/TpywPDKioSI/AAAAAAAAGbo/iu2wo3nSr5U/s1600/f18_afterburner_takeoff.jpg1
• To simulate ground effect • To simulate propulsion systems tightly integrated
with the airframes in futuristic aircraft designs
Flat plate with rectangular nozzle
Flat plate with circular nozzle
7. Shadowgraph and Schlieren
Flow Visualization
Shadowgraph Schlieren
• High-speed Flow Visualization
• Frame Rate = 25KHz
• Phantom v1610/v1210 high-speed cameras
• Jet-surface interaction study
• Strong screech instability captured
(scroll down to watch videos)
Screech Waves
8. 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
100
200
300
400
500
600
700
800
Ux
ave
(m/s)
x/D
Dashed – Exp. PIV
Solid – CFD
100% ∗ 𝑻𝑲𝑬
Ujet,isen
2
TKE
Ux Ux
(m/s)
- Velocity measurements matched with results from LES simulations
* Hafsteinsson, H., Eriksson, L., Andersson, N., Mora, P., and Gutmark, E.J., “Exploration of temperature effects on the far-field acoustic radiation from a supersonic jet,” 20th AIAA/CEAS Aeroacoustics Conference, Atlanta,
Georgia, 2014, AIAA-2014-2454
High-temperature supersonic jet
1. 5 design Mach number, and Temperature Ratio of 3.0
PIV and Microphone Arrangements
Streamwise PIV
Jet Velocity and Turbulence Measurements
9. Acoustic Measurements
Microphone Array
X
y
55o
10o
Flow
Baseline Chevrons
SPL
St=0.2
dP/dt
Skewness
Near-field microphone array
on traverse system
• Contour plots of near-field noise statistics
• Identifying noise source location and propagation patterns
• Noise mitigation with chevrons
Traverse
[dB]
10. Geometry - Mesh
- Design Mach Number = 1.5
- Throat Diameter = 0.75in
- Throat Radius of Curvature = 4in
- 3D Mesh, 336875 cells
RANS
- Turbulence Model: Realizable k-epsilon
- Discretization: Second Order
- Inlet Total Temp = 700K
- Inlet Total Press = 388547 Pa
- No-slip condition
Mach Number Contours
Contoured Nozzle
Design of a Shock-Free Nozzle
Sharp-Throat
Circular Nozzle
Internal Contours designed by
the Method of Characteristics
CFD simulations before nozzle fabrication
Conical Nozzle with sharp throat: Double shock-cell
Potential Core breaks down further upstream for heated jets
Shock-cell spacing remains similar for different temperature ratios
Results matching LES simulations
Shear layer TKE levels increased with temperature
