{"id":766,"date":"2021-06-15T20:41:28","date_gmt":"2021-06-15T20:41:28","guid":{"rendered":"https:\/\/faculty.engineering.ucdavis.edu\/slee-new\/?page_id=766"},"modified":"2026-01-01T17:03:51","modified_gmt":"2026-01-02T01:03:51","slug":"research","status":"publish","type":"page","link":"https:\/\/faculty.engineering.ucdavis.edu\/slee\/research\/","title":{"rendered":"Research and CFPA Lab"},"content":{"rendered":"\t\t<div data-elementor-type=\"wp-page\" data-elementor-id=\"766\" class=\"elementor elementor-766\">\n\t\t\t\t\t\t<section class=\"elementor-section elementor-top-section elementor-element elementor-element-41c7fed1 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"41c7fed1\" data-element_type=\"section\" data-e-type=\"section\" data-settings=\"{&quot;background_background&quot;:&quot;classic&quot;}\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t<div class=\"elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-68101592\" data-id=\"68101592\" data-element_type=\"column\" data-e-type=\"column\" data-settings=\"{&quot;background_background&quot;:&quot;classic&quot;}\">\n\t\t\t<div class=\"elementor-widget-wrap elementor-element-populated\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-28962488 elementor-widget elementor-widget-page-title\" data-id=\"28962488\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"page-title.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\n\t\t<div class=\"hfe-page-title hfe-page-title-wrapper elementor-widget-heading\">\n\n\t\t\t\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">\n\t\t\t\t\t\t\t\t\n\t\t\t\tResearch and CFPA Lab  \n\t\t\t<\/h2 > \n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-5d618ae3 elementor-widget-divider--view-line elementor-widget elementor-widget-divider\" data-id=\"5d618ae3\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"divider.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<div class=\"elementor-divider\">\n\t\t\t<span class=\"elementor-divider-separator\">\n\t\t\t\t\t\t<\/span>\n\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-498b0c4a elementor-widget elementor-widget-text-editor\" data-id=\"498b0c4a\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><a href=\"https:\/\/engineering.ucdavis.edu\/news\/vertical-vision-shaping-air-taxi-revolution\" target=\"_blank\" rel=\"noopener\"><b>Our Lab Research Highlight I&nbsp;<\/b><\/a><\/p>\n<p><a href=\"https:\/\/mae.ucdavis.edu\/news\/your-flying-taxi-almost-here\" target=\"_blank\" rel=\"noopener\"><b>Our Lab Research Highlight II<\/b><\/a><\/p>\n<p><b>Current Research Funding:<\/b><\/p>\n<ul>\n<li>Multi-Discipline Integrated UAM Core Technology Development Center, <b>National Research Foundation of Korea<\/b> (2025-2028) (<a href=\"http:\/\/uam-erc.snu.ac.kr\/eng\/main\/main.html\" target=\"_blank\" rel=\"noopener\">website 1<\/a>,&nbsp;<a href=\"https:\/\/aarlthird.synology.me:5001\/fsdownload\/ZBRTvuLO0\/%EC%84%A0%EB%8F%84%EC%97%B0%EA%B5%AC%EC%84%BC%ED%84%B0%20%EA%B3%B5%EC%9C%A0(UAM)\" target=\"_blank\" rel=\"noopener\">website 2<\/a>)<\/li>\n<li><span style=\"background-color: transparent;color: var( --e-global-color-text );font-weight: var( --e-global-typography-primary-font-weight )\">Proprotor and Wing Interactional Aerodynamics for Performance, Acoustics, and Vibration, <\/span><strong style=\"background-color: transparent;color: var( --e-global-color-text )\">US Army VLRCOE<\/strong><span style=\"background-color: transparent;color: var( --e-global-color-text );font-weight: var( --e-global-typography-primary-font-weight )\">&nbsp;(2021-2026) (<\/span><a style=\"font-weight: var( --e-global-typography-primary-font-weight )\" href=\"https:\/\/www.vlrcoe.psu.edu\/\" target=\"_blank\" rel=\"noopener\">website<\/a><span style=\"background-color: transparent;color: var( --e-global-color-text );font-weight: var( --e-global-typography-primary-font-weight )\">)<\/span><\/li>\n<\/ul>\n<p><strong><br>Past Research Funding:<br><\/strong><\/p>\n<ul>\n<li style=\"font-size: 16px\">Rapid Development of Urban Air Mobility Vehicle Concepts through Full-Configuration Multidisciplinary Design, Analysis, and Optimization,&nbsp;<span style=\"font-weight: bolder\">NASA ULI<\/span>&nbsp;(2021-2025) (<a href=\"https:\/\/sites.google.com\/eng.ucsd.edu\/uli\/home?authuser=0\" target=\"_blank\" rel=\"noopener\">website<\/a>)<\/li>\n<li style=\"font-size: 16px\">High-Performance, Zero-Emission, and Ultra-Quiet Aircraft Design and Operation with Over-the-Wing Distributed Propellers,&nbsp;<span style=\"font-weight: bold\">UC Davis College of Engineering&nbsp;<\/span>(2023-2024) (<a href=\"https:\/\/engineering.ucdavis.edu\/next-level-research-awards#project4\" target=\"_blank\" rel=\"noopener\">website<\/a>)<\/li>\n<li style=\"font-size: 16px\"><span style=\"background-color: transparent\">Multi-Particle Transport in a Complex Flow Field with Surface Impact (Dynamic Stall in Harsh Environments),&nbsp;<span style=\"font-weight: bold\">Lawrence Livermore National Laboratory<\/span>&nbsp;(2023-2024) (<a href=\"https:\/\/www.llnl.gov\/news\/six-lab-scientists-partner-university-researchers-through-wcis-act-awards\" target=\"_blank\" rel=\"noopener\">website<\/a>)<\/span><\/li>\n<li style=\"font-size: 16px\"><span style=\"background-color: transparent\">High-Fidelity CFD Simulations for Tonal and Broadband Noise Predictions of Urban Air Mobility Aircraft,&nbsp;<\/span><span style=\"font-weight: bolder;background-color: transparent\">Supernal<\/span><span style=\"background-color: transparent\">&nbsp;(2021-2023)<\/span><\/li>\n<li>Broadband Noise Prediction Code Development and Optimization of Low Noise Airfoil, <strong>Hyundai<\/strong>&nbsp;(2019-2020)<\/li>\n<li>Toward Quiet Transformative Electric Vertical Aircraft, <strong style=\"background-color: transparent\">Hellman Foundation<\/strong><span style=\"background-color: transparent\">&nbsp;(2018)<\/span><\/li>\n<li>Loads Data Generation for Offshore Wind Turbine Rotor on Multi-Purposed Mobile Base, <strong>KIMM<\/strong> (Korea Institute of Machinery and Materials) (2016-2017)<\/li>\n<li>Fundamental Aeroacoustics of Coaxial Helicopter Rotors, <strong>US Army VLRCOE<\/strong>&nbsp;(2016-2020)<\/li>\n<\/ul>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-e8d4220 elementor-widget elementor-widget-text-editor\" data-id=\"e8d4220\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><strong>Research Topics:<\/strong><\/p>\n<ul>\n<li><strong>Turbulent Flow and Airfoil Noise<br><\/strong>Aeroacoustics, an interdisciplinary field that combines fluid mechanics and acoustics, is dedicated to examining noise generation caused by turbulent fluid motion or aerodynamic forces interacting with surfaces. To address this challenging yet crucial issue, we are delving into the complex, unsteady fluid dynamics and turbulent flows, while also formulating new theories and computational algorithms to forecast the inception and transmission of aerodynamically induced noise.&nbsp;<span style=\"background-color: transparent;color: var( --e-global-color-text );font-weight: var( --e-global-typography-primary-font-weight )\">One notable example in this domain is the turbulent boundary layer trailing-edge noise of airfoils. We are in the process of devising efficient and precise numerical methods to predict trailing edge noise. Additionally, we employ Large Eddy Simulations (LES) to scrutinize the intricate flow physics related to noise generation and propagation.&nbsp;<\/span><span style=\"background-color: transparent;color: var( --e-global-color-text );font-weight: var( --e-global-typography-primary-font-weight )\">Our research endeavors contribute significantly to the advancement of aerospace engineering and science, as well as the fundamental knowledge and comprehension of unsteady flows, turbulence, and aeroacoustics.<\/span><\/li>\n<\/ul>\n<p><img fetchpriority=\"high\" decoding=\"async\" class=\"aligncenter\" src=\"https:\/\/faculty.engineering.ucdavis.edu\/slee\/wp-content\/uploads\/sites\/34\/2022\/01\/LES-1024x296.jpg\" alt=\"\" width=\"800\" height=\"231\">&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;<img decoding=\"async\" class=\"aligncenter\" src=\"https:\/\/faculty.engineering.ucdavis.edu\/slee\/wp-content\/uploads\/sites\/34\/2022\/03\/LES2-1024x770.jpg\" alt=\"\" width=\"500\" height=\"376\"><\/p>\n<p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; (Image credit: Donghun Kang (PhD student) &#8211; LES for airfoil noise)<\/p>\n<ul>\n<li><strong>Rotorcraft Aerodynamics and Aeroacoustics<br><\/strong>Rotorcraft possess the unique ability to hover and perform vertical take-offs and landings. However, noise generated by rotorcraft poses challenges in terms of public acceptance in urban environments and detection in military operations. To address these issues, we utilize high-fidelity computational fluid dynamics (CFD) and computational structural dynamics (CSD) coupling simulations to calculate aerodynamic forces, wake flows, and elastic blade motions. Based on these flow fields and trim solutions, we predict the tonal and broadband noise produced by rotating blades. A recent application of our research focuses on transformative electric vertical take-off and landing (eVTOL) aircraft, also known as urban air mobility or air taxis. Additionally, we have developed a novel rotor broadband noise software called UCD-QuietFly, which has gained widespread adoption in both academia and industry. By exploring innovative ideas to reduce rotorcraft noise, we aim to improve public acceptance of rotorcraft in urban settings and minimize the detection of rotorcraft during military operations.<\/li>\n<\/ul>\n<p><img decoding=\"async\" class=\"aligncenter\" src=\"https:\/\/faculty.engineering.ucdavis.edu\/slee\/wp-content\/uploads\/sites\/34\/2021\/06\/Lab_Research-1024x285.jpg\" alt=\"lab research\" width=\"800\" height=\"223\"><\/p>\n<p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;(Image credit: Henry Jia (PhD student) &#8211; Lift-offset coaxial rotor CFD simulations)<\/p>\n<p><strong>&nbsp; <img loading=\"lazy\" decoding=\"async\" class=\"aligncenter\" src=\"https:\/\/faculty.engineering.ucdavis.edu\/slee\/wp-content\/uploads\/sites\/34\/2022\/05\/SidebySide.jpg\" alt=\"\" width=\"600\" height=\"437\"><\/strong><\/p>\n<p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; (Image credit: Jared Sagaga (PhD student) &#8211; Side-by-side rotor CFD simulations)<\/p>\n<ul>\n<li><span style=\"font-weight: bolder;color: var( --e-global-color-text );background-color: transparent\">Propeller Aerodynamics and Aeroacoustics &amp; Aircraft Engine Noise<br><\/span>With the advent of electric aircraft, propeller noise has garnered renewed interest. This renewed focus is crucial for addressing the unique challenges and demands of electric propulsion systems, ensuring their integration into the aviation industry while minimizing the impact on the environment and communities. We are working on predicting propeller tonal and broadband noise by utilizing low-, medium-, and high-fidelity computational models. Additionally, we explore innovative concepts to mitigate propeller noise. Our efforts extend to the application of the propeller and wing interaction and its impact on aircraft performance, aerodynamics, and acoustics. Furthermore, we investigate the interaction of aircraft engine noise with the fuselage, which is considered an acoustic scattering problem or propulsion airframe integration.<img loading=\"lazy\" decoding=\"async\" class=\"aligncenter\" style=\"background-color: transparent;color: var( --e-global-color-text );font-weight: var( --e-global-typography-primary-font-weight )\" src=\"https:\/\/faculty.engineering.ucdavis.edu\/slee\/wp-content\/uploads\/sites\/34\/2022\/01\/Quadrotor_CFD-1024x524.png\" alt=\"\" width=\"800\" height=\"409\"><span style=\"background-color: transparent;color: var( --e-global-color-text );font-weight: var( --e-global-typography-primary-font-weight )\"><span style=\"background-color: transparent;color: var( --e-global-color-text );font-weight: var( --e-global-typography-primary-font-weight )\">&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;(Image credit: Henry Jia (PhD student) &#8211; Quadrotor full vehicle CFD)<\/span><\/span><\/li>\n<li><strong>Wind Energy Aerodynamics and Aeroacoustics<br><\/strong>Wind energy is experiencing exponential growth worldwide and has recently emerged as a mainstream source of power. To further reduce the cost of wind energy and expedite wind turbine installations, it is crucial to enhance aerodynamic efficiency and optimize wind energy capture. Moreover, wind turbine noise has become a concern for obtaining building permits in residential areas. Our lab focuses on wind turbine aerodynamics and aeroacoustic research. One specific area of interest is unsteady aerodynamics and dynamic stall prediction and mitigation. We employ computational fluid dynamics (CFD) to advance technology and knowledge in wind energy. Our research contributes to the development of next-generation environmentally friendly renewable energy sources.&nbsp;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;<br>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&nbsp;<img loading=\"lazy\" decoding=\"async\" class=\"aligncenter\" style=\"background-color: transparent\" src=\"https:\/\/faculty.engineering.ucdavis.edu\/slee\/wp-content\/uploads\/sites\/34\/2022\/01\/DynamicStall2.jpg\" alt=\"\" width=\"705\" height=\"166\"><span style=\"background-color: transparent\"><span style=\"background-color: transparent\"><span style=\"background-color: transparent\"><span style=\"background-color: transparent\">&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;(Image credit: Jagdeep Batther (MS student) &#8211; Dynamic stall prediction using DDES)<\/span><\/span><\/span><\/span><\/li>\n<\/ul>\n<p><br><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t<\/div>\n\t\t","protected":false},"excerpt":{"rendered":"<p>Research and CFPA Lab Our Lab Research Highlight I&nbsp; Our Lab Research Highlight II Current Research Funding: Multi-Discipline Integrated UAM Core Technology Development Center, National Research Foundation of Korea (2025-2028) (website 1,&nbsp;website 2) Proprotor and Wing Interactional Aerodynamics for Performance, Acoustics, and Vibration, US Army VLRCOE&nbsp;(2021-2026) (website) Past Research Funding: Rapid Development of Urban Air [&hellip;]<\/p>\n","protected":false},"author":7,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"inline_featured_image":false,"footnotes":""},"class_list":["post-766","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/faculty.engineering.ucdavis.edu\/slee\/wp-json\/wp\/v2\/pages\/766","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/faculty.engineering.ucdavis.edu\/slee\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/faculty.engineering.ucdavis.edu\/slee\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/faculty.engineering.ucdavis.edu\/slee\/wp-json\/wp\/v2\/users\/7"}],"replies":[{"embeddable":true,"href":"https:\/\/faculty.engineering.ucdavis.edu\/slee\/wp-json\/wp\/v2\/comments?post=766"}],"version-history":[{"count":223,"href":"https:\/\/faculty.engineering.ucdavis.edu\/slee\/wp-json\/wp\/v2\/pages\/766\/revisions"}],"predecessor-version":[{"id":3303,"href":"https:\/\/faculty.engineering.ucdavis.edu\/slee\/wp-json\/wp\/v2\/pages\/766\/revisions\/3303"}],"wp:attachment":[{"href":"https:\/\/faculty.engineering.ucdavis.edu\/slee\/wp-json\/wp\/v2\/media?parent=766"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}