@article{chen_liu_chen_wimsatt_2024, title={Aeroacoustic and aerodynamic measurements at the rotor plane in the interaction of a small rotor with wings}, url={https://doi.org/10.1121/10.0032471}, DOI={10.1121/10.0032471}, journal={The Journal of the Acoustical Society of America}, author={Chen, Mingtai and Liu, Lucy and Chen, Yuhan and Wimsatt, Jacob}, year={2024}, month={Oct} }
 @article{chen_chen_hua_maier_burdette_2024, title={Experimental assessment of blowing effect on vehicle performance and aero-acoustics in small-rotor/wing interaction}, volume={3}, ISSN={["1741-2986"]}, url={https://doi.org/10.1177/10775463241236303}, DOI={10.1177/10775463241236303}, abstractNote={ The tiltrotor design for urban air mobility (UAM) combines vertical take-off and landing (VTOL) capability with fixed-wing efficiency. However, it confronts challenges posed by downward force due to rotor wake effect. Previous research has employed active flow control, such as blowing air, primarily during forward flight using a single air outlet slot. However, the implications for rotor performance and aero-acoustic characteristics have remained unexplored. The experimental approach in this study involves controlled blowing air with moderate momentum in hover mode, concentrating on rotor performance, download force, noise signature, and the influence of port patterns. It is found that the radial port pattern emerges as pivotal for mitigating downward force and augmenting rotor efficiency. The efficacy of noise reduction hinges on both receiver orientation and port pattern selection. This investigation significantly contributes to understanding the role of blowing effect in optimizing tiltrotor designs, particularly in the context of rotor wake-wing interaction. }, journal={JOURNAL OF VIBRATION AND CONTROL}, author={Chen, Mingtai and Chen, Yuhan and Hua, Jie and Maier, Nick and Burdette, Dylan}, year={2024}, month={Mar} }
 @article{chen_2024, title={Facilitating aerospace engineering senior design: Integrating lab curriculum redesign with student project and new technologies}, volume={6}, ISSN={["2577-8196"]}, url={https://doi.org/10.1002/eng2.12938}, DOI={10.1002/eng2.12938}, abstractNote={Abstract This study addresses a gap in existing literature by exploring the impact of an aerodynamics laboratory course on students' readiness for senior design projects in Aerospace Engineering at North Carolina State University. The redesigned curriculum focuses on propellers, aligning with the increasing popularity of senior design projects involving fixed‐wing aircraft and multi‐rotor systems in the Mechanical and Aerospace Engineering Department. The updated course incorporates Additive Manufacturing (AM) and an anechoic chamber for the first time, outlining its structure, objectives, and pivotal concepts. The use of data acquisition codes streamlines experimentation while integrating AM accelerates practical applications of blade element theory (BET). Through an assessment of lab report grades, this initiative significantly enhances students' grasp of propeller concepts, marking a pivotal step in their preparation for senior design projects.}, journal={ENGINEERING REPORTS}, author={Chen, Mingtai}, year={2024}, month={Jun} }
 @article{chen_2024, title={Synergizing computer-aided design, commercial software, and cutting-edge technologies in an innovative nozzle test apparatus for an engineering laboratory course}, volume={6}, ISSN={["1099-0542"]}, url={https://doi.org/10.1002/cae.22773}, DOI={10.1002/cae.22773}, abstractNote={Abstract This study explores compressible flow, a field reliant on mathematical models for effective teaching. Using laboratory experiments as pedagogical tools, we introduce a compact nozzle test apparatus that integrates cutting‐edge technologies—additive manufacturing (AM), pressure‐sensitive paint, the Schlieren system, image processing, and computational fluid dynamics (CFD)—in a compressible flow laboratory course. Commercial software, including MATLAB, SOLIDWORKS, ANSYS Fluent, and LabVIEW, facilitates the incorporation of these technologies. The research outlines the course structure, objectives, and details of student projects. Through a comparative analysis of experimental results, analytical calculations, and CFD simulations, we showcase the successful integration of AM in pedagogical practices for compressible flow, addressing critical concerns like nozzle strength and surface roughness. Statistical data from student projects offer practical insights, ensuring accuracy in experimental applications. The laboratory's design and detailed lists of components and costs provide a meaningful comparison with a supersonic wind tunnel, considering manufacturing expenses, operational costs, spatial requirements, and noise levels. The assessment of lab report grades underscores the approach's efficacy in conveying compressible flow concepts successfully, facilitated by modern computers. In summary, our study presents a comprehensive, efficient, and technologically advanced approach to teaching compressible flow within a concise framework.}, journal={COMPUTER APPLICATIONS IN ENGINEERING EDUCATION}, author={Chen, Mingtai}, year={2024}, month={Jun} }
 @inproceedings{tip vortex trajectory and its application in small-rotor/wing interaction_2024, DOI={10.2514/6.2024-2846}, abstractNote={This paper studies the downward tip vortex trajectory of a small rotor in the near proximity of a wing, similar to the geometry of small unmanned-air-vehicles (UAVs) in hover (disk loading < 100 N/m^2 and Reynolds number < 100,000). Rotor height above the wing and rotor wake impingement area on the wing are varied. Empirical equations of the trajectory as a function of rotor height generalized from tip vortex trajectory results in smoke visualization experiments are then employed. Using the rotor wake model based on the tip vortex trajectories, image vortices, and momentum theory, a potential flow solution to predict rotor thrust and download force on the wing is developed and discussed, which links rotor wake, thrust and download force in rotor-wing interaction. The analytical results will be compared to the corresponding experimental force data in terms of magnitude and trend for accuracy assessment.}, booktitle={AIAA SCITECH 2024 Forum}, year={2024}, month={Jan} }
 @article{ling_chen_liu_yin_2023, title={A Modified Hand-Held Force Meter to Measure Yarn Tension in the Ring Spinning Process}, volume={7}, ISSN={["1875-0052"]}, url={http://dx.doi.org/10.1007/s12221-023-00271-z}, DOI={10.1007/s12221-023-00271-z}, journal={FIBERS AND POLYMERS}, publisher={Springer Science and Business Media LLC}, author={Ling, Yali and Chen, Mingtai and Liu, Yang and Yin, Rong}, year={2023}, month={Jul} }
 @article{chen_hua_maier_burdette_2023, title={Acoustic measurements in single-rotor/wing interaction at low disk loading and Reynolds number}, volume={12}, ISSN={["2048-4003"]}, url={https://doi.org/10.1177/1475472X231225630}, DOI={10.1177/1475472X231225630}, abstractNote={ The tiltrotor design is favored for urban air mobility (UAM) prototypes due to the combination of vertical takeoff and landing (VTOL) capability and efficient forward flight. With rising UAM air traffic at low altitudes, noise from these aircraft is a crucial design factor. Most tiltrotor noise research focuses on high disk loading and Reynolds number setups, leaving smaller aircraft configurations less explored. This study investigates aero-acoustic trends from rotor-wing interaction at low disk loading ([Formula: see text]100 N/m2) and Reynolds number (Re < 100,000). While prior literature suggests lowering disk loading and reducing rotor wake interference can mitigate rotor noise, such ideas lack empirical validation. The setup involves an anechoic chamber housing a two-blade rotor, along with flat and NACA 0012 airfoil wings. Microphones and a rotation stage capture acoustic data for analysis. Factors like flow recirculation, isolated rotor noise, rotor height, rotation direction/rate, and wing curvature are assessed for impact on noise signature. It is found that the deflected rotor wake in rotor-wing interaction significantly increases low-frequency broadband noise and overall sound pressure level (OASPL), compared to an isolated rotor. Dominant tonal noise diminishes based on the strength of the deflected rotor wake. These findings offer insights into reducing noise from rotor wake impingement on the wing. }, journal={INTERNATIONAL JOURNAL OF AEROACOUSTICS}, author={Chen, Mingtai and Hua, Jie and Maier, Nick and Burdette, Dylan}, year={2023}, month={Dec} }
 @article{chen_hua_ling_liu_chen_ju_gao_mills_tao_yin_2023, title={An airflow-driven system for scalable production of nano-microfiber wrapped triboelectric yarns for wearable applications}, volume={477}, ISSN={["1873-3212"]}, url={https://doi.org/10.1016/j.cej.2023.147026}, DOI={10.1016/j.cej.2023.147026}, journal={CHEMICAL ENGINEERING JOURNAL}, author={Chen, Yu and Hua, Jie and Ling, Yali and Liu, Yang and Chen, Mingtai and Ju, Beomjun and Gao, Wei and Mills, Amanda and Tao, Xiaoming and Yin, Rong}, year={2023}, month={Dec} }
 @inproceedings{chen_power_stults_mohan_baby_2023, title={Experimental Investigation of Surface Roughness on the Flowfield and Aero-acoustics of Converging Nozzles}, url={http://dx.doi.org/10.2514/6.2023-4447}, DOI={10.2514/6.2023-4447}, abstractNote={This paper investigates the effects of the surface roughness on the flowfield and aero-acoustics of a CNC-milled and 3D-printed converging nozzle at relatively large Reynolds number (Re = 400,000 -- 620,000). A novel nondestructive scanning method is used to quantify the surface roughness of both nozzles. A comparison of the maximum surface roughness reveals that the 3D-printed converging nozzle has a rougher surface. Pressure measurements, images from the Schlieren system, and acoustic data are acquired from the two nozzles installed on a nozzle test apparatus and compared. Experimental results show that the 3D-printed converging nozzle performs similarly to the CNC-milled converging nozzle, except that it has a larger tonal noise at a slightly higher frequency. The comparisons demonstrate that the 3D-printed converging nozzle can be employed to quickly demonstrate and verify novel ideas and concepts in the pedagogy and research at relatively large Reynolds number.}, booktitle={AIAA AVIATION 2023 Forum}, publisher={American Institute of Aeronautics and Astronautics}, author={Chen, Mingtai and Power, Hunter and Stults, Emma and Mohan, Anil and Baby, Ruksana}, year={2023}, month={Jun} }
 @article{chen_baby_dillard_lee_ekkad_2022, title={Design and test a converging and de Laval nozzle using additive manufacturing}, volume={1}, url={http://dx.doi.org/10.3389/fpace.2022.951987}, DOI={10.3389/fpace.2022.951987}, abstractNote={The advent of additive manufacturing technology has facilitated the design and fabrication of parts and models in both academia and aerospace industry. Compressible flow in the nozzles is not a new research topic; however, the accuracy of the experimental results obtained from the nozzles using additive manufacturing has not been assessed comprehensively. Surface roughness and strength of 3D-printed nozzles are two major concerns when they are applied to compressible flows. In this paper, a converging and a de Laval nozzle fabricated by additive manufacturing using ABS filament are designed and tested. Surface roughness inside the converging nozzle is quantified using a nondestructive method. In general, the experimental results compare well with the analytical solutions from isentropic equations for the converging nozzle and the numerical simulations conducted in ANASYS Fluent for the de Laval nozzle. 3D-printed nozzles can be employed to quickly demonstrate and verify novel ideas and concepts in the pedagogy and research at large Reynolds numbers.}, journal={Frontiers in Aerospace Engineering}, publisher={Frontiers Media SA}, author={Chen, Mingtai and Baby, Ruksana and Dillard, Seth and Lee, Yi Tsung and Ekkad, Srinath}, year={2022}, month={Aug} }
 @inproceedings{chen_shen_hubner_2022, title={Investigation of Fountain Effect in Dual-Rotor/Wing Interaction at Low Reynolds Number}, DOI={10.2514/6.2022-3816}, abstractNote={This paper conducts a parametric investigation on whether the fountain effect in dual rotor/wing interaction exists at low disk loading and Reynolds number (disk loading < 100 N/m^2 and Reynolds number < 100,000). A commercial computational fluid dynamics package specifically developed for rotorcraft studies, RotCFD, in which the rotor is modeled as a distribution of momentum sources, was used. Numerical results are compared to an experimental study including force measurements and surface pressure measurements. The comparisons are employed to assess the accuracy of RotCFD results and help evaluate the formation of the fountain effect and its effect on rotor thrust and download force on the wing.}, booktitle={AIAA AVIATION 2022 Forum}, author={Chen, M. and Shen, J. and Hubner, J.P.}, year={2022}, month={Jun} }
 @inproceedings{hedge_macintyre_hubner_chen_pandey_flood_casper_2022, title={Pressure and Strain Measurement on a 10° Control Surface of a Slender Cone in Hypersonic Flow}, DOI={10.2514/6.2022-4043}, abstractNote={This paper presents the results of an experimental technique to acquire full-field pressure and strain fields on the windward side of a 10° flap attached to a slender cone-slice model. Tests were conducted in the Hypersonic Wind Tunnel (M = 5, Re= 9 – 14×〖10〗^6/m, air) at Sandia National Laboratories. The flap was coated with a fast-response, pressure-sensitive paint sprayed over a photoelastic coating and located near the trailing-edge of an axial slice along the 7° slender cone. This experiment was part of a sponsored project to develop the two-coating luminescent measurement technique and apply to high-speed, fluid-structure interaction environments. Results using a low-speed micropolarizer camera with four polarization orientations show that the technique is sensitive to pressure and strain, measuring an increasing pressure and decreasing strain from leading- to trailing-edge over the surface of the flap. At the low Re condition, the pressure signal captures the separated region near the flap leading edge and compares well with schlieren and oil-film measurements, the latter on a 10° wedge. Aerodynamic heating during the run does affect the pressure signal, likely resulting in an overestimation of pressure. Results using a conventional high-speed camera with a single linear polarizer captures the first bending and torsional modes of vibration when the flap is excited by transient shutdown conditions; however, coupling is difficult to detect in the pressure response due to baseline noise and the slower temporal response of the pressure coating.}, booktitle={AIAA AVIATION 2022 Forum}, author={Hedge, A. and MacIntyre, Z. and Hubner, J.P. and Chen, M. and Pandey, A. and Flood, J.T. and Casper, K.M.}, year={2022}, month={Jun} }
 @article{chen_hubner_2021, title={Experimental and Analytical Analysis of Rotor-Wing Interaction in hover for Low Reynolds Number Flow}, volume={34}, url={https://doi.org/10.1061/(ASCE)AS.1943-5525.0001307}, DOI={10.1061/(ASCE)AS.1943-5525.0001307}, abstractNote={AbstractHover performance for tiltrotor-like vehicles lacks experimental data and computationally efficient models for single-rotor-wing interactions at low disk loadings and low Reynolds numbers. ...}, number={6}, journal={Journal of Aerospace Engineering}, author={Chen, M. and Hubner, J.P.}, year={2021}, month={Nov}, pages={04021073} }
 @inproceedings{chen_hubner_2021, title={Numerical Simulations of Single-Rotor/Wing Interaction in Hover at Low Reynolds Number}, DOI={10.2514/6.2021-2592}, abstractNote={RotCFD, a computational fluid dynamics package specifically developed for rotorcraft studies, was used to investigate the rotor wake impingement of small tiltrotor-like vehicles (Reynolds number < 100,000 and disk loading < 100 N/m2) on a flat plate (aspect ratio equal to four) simulating a generic wing. Results are compared to a comprehensive experimental study including force measurements, surface pressure measurements, and tip vortex trajectory measurements. The comparisons are employed to assess the accuracy of RotCFD results and help explain the aerodynamic mechanisms that increase both rotor thrust and download force when the rotor is the proximity of the flat plate.}, booktitle={AIAA AVIATION 2021 FORUM}, author={Chen, M. and Hubner, J.P.}, year={2021}, month={Aug} }
 @phdthesis{parametric investigation of aerodynamic interaction between two rotors and a flat plate at low reynolds number_2021, year={2021}, month={May} }
 @inproceedings{hedge_chen_olcmen_hubner_crafton_ryan_2021, title={Pressure and Strain Measurement on a Thin Clamped Plate in Supersonic Flow using a Dual-Layer Luminescent Coating}, DOI={10.2514/6.2021-2920}, abstractNote={This paper discusses the application of a dual-layer luminescent coating to measure the pressure and strain on a thin, circular clamped plate subjected to an impinging shock-wave boundary layer interaction (SWBLI) in Mach 2.9 flow. The two-coating technique uses a fast-response pressure sensitive paint applied over a photoelastic coating adhered to the surface of the plate. The technique, theory, instrumentation, experimental results, and measurement resolution are discussed.}, booktitle={AIAA AVIATION 2021 FORUM}, author={Hedge, A. and Chen, M. and Olcmen, S.M. and Hubner, J.P. and Crafton, J. and Ryan, C.}, year={2021}, month={Aug} }
 @article{chen_hubner_2021, title={Experimental Investigation of Wing-on-Rotor Effect at Low Disk Loading and Reynolds Number}, volume={58}, DOI={10.2514/1.C035763}, abstractNote={Hover performance and prediction for tiltrotor-like vehicles lack experimental data and computational models for rotor–wing interaction at low disk loading and low Reynolds number. An experimental ...}, number={3}, journal={Journal of Aircraft}, author={Chen, M. and Hubner, J.P.}, year={2021}, month={May}, pages={487–496} }
 @inproceedings{chen_hubner_2020, title={Prediction of Dual-Rotor-Wing Interaction in Hover Using Actuator Disk Theory}, DOI={10.2514/6.2020-2793}, abstractNote={This paper details a potential flow solution for dual-rotor-wing interactions based on actuator disk theory, the method of images and momentum theory in terms of rotor thrust and wing download force of small tiltrotor-like vehicles. The regime of interest is Reynolds number < 100,000 and disk loading < 100 N/m2. The analytical model examines the effect of rotor height above the wing, the rotor disk coverage over the wing, and the spacing between two rotors. The analytical model requires the rotor radius, which assists in preliminary design studies on tiltrotor-like vehicles. The analytical results compare well with the experimental data in terms of magnitude and trend, particularly the rotor thrust.}, booktitle={AIAA AVIATION 2020 FORUM}, author={Chen, M. and Hubner, J.P.}, year={2020}, month={Jun} }
 @inproceedings{chen_cranes_hubner_2019, title={Experimental Investigation of Rotor-Wing Interaction at Low Disk Loading and Low Reynolds Number}, DOI={10.2514/6.2019-3034}, booktitle={AIAA Aviation 2019 Forum}, author={Chen, M. and Cranes, D. and Hubner, J.P.}, year={2019}, month={Jun} }
 @inproceedings{rotor wing interaction of the low reynolds numbers_2019, year={2019} }
 @book{chen_2013, place={Shanghai}, title={Civil Airplane Flight Test Introduction for Special Flight Service and Ground Support Condition}, ISBN={9787313096944}, publisher={Shanghai Jiaotong University Press}, year={2013} }
 @book{civil airplane flight test introduction for special flight service and ground support condition_2013, year={2013} }
 @book{chen_2013, place={Shanghai}, title={Transport Category Aircraft Certification Flight Test Guide}, publisher={Shanghai Jiaotong University Press}, author={Chen, M.}, year={2013} }
 @book{transport category aircraft certification flight test guide_2013, year={2013} }
 @inproceedings{mi_chen_2012, title={A Method for Correcting The Error in Indicated Normal Acceleration Due to GSensor Location}, url={http://dx.doi.org/10.2991/iccasm.2012.135}, DOI={10.2991/iccasm.2012.135}, abstractNote={Particularly for structural purposes, it is important to obtain accurate measurements of the normal acceleration at the Center of Gravity of an aircraft. For most airliners and fighters, the g-sensors are located away from the Center of Gravity (C.G.). Theoretical mechanics shows that, depending on the distance between the g-sensor and the C.G., aircraft angular rates and accelerations will induce a difference between the actual normal acceleration at the C.G. and the normal acceleration indicated by the g-sensor. A method was devised to correct the normal acceleration indicated by the gsensor so as to obtain the actual normal acceleration at the aircraft C.G. Based on the method presented in this paper, tests were conducted on the B737-800 simulator and the corrections determined by the method were compared with the test data obtained from the simulator. Keywords-Normal Acceleration, Correction, g-sensor, C.G., Aircraft}, booktitle={Proceedings of the 2nd International Conference on Computer Application and System Modeling}, publisher={Atlantis Press}, author={Mi, Yi and Chen, Mingtai}, year={2012}, month={Aug} }
 @inproceedings{chen_2012, title={Static Thrust Measurement for Propeller-driven Light Aircraft}, url={http://dx.doi.org/10.2991/iccasm.2012.165}, DOI={10.2991/iccasm.2012.165}, abstractNote={Since in-flight thrust is a calculation based upon a number of separate measurements. Only on the ground, either in an engine cell or during a static thrust run, do we actually measure thrust using load cells. In this thesis a device was devised to measure the static thrust of propeller-driven light aircraft. Also a static thrust model of propeller-driven light aircraft was established to compare with test results. Three propeller-driven light aircrafts were tested with different diameters of propeller. The propellers of all three aircrafts were connected to engine shaft directly without gear box between the propeller and engine shaft so that propeller revolution speed was regarded to equal to engine revolution speed (RPM). KeywordsIn flight thrust, Load cell, Static thrust, Propeller revolution speed, Engine RPM}, booktitle={Proceedings of the 2nd International Conference on Computer Application and System Modeling}, publisher={Atlantis Press}, author={Chen, Mingtai}, year={2012}, month={Aug} }
 @inproceedings{zhang_chen_mi_liu_2012, title={The Design of Control Force Measurement Device for Aircraft Quick Evaluation Flight Test}, url={http://dx.doi.org/10.2991/iccasm.2012.163}, DOI={10.2991/iccasm.2012.163}, abstractNote={The design and installation of control force measurement device for quick evaluation flight test was difficult due to not enough time and fund available. Three control force indication devices were assembled and tested. They were spring balance, control force indication glove and FlexiForce indicator. The flight test results showed that all the three devices could be used for quick control force measurement. The principle of control force indication glove was innovative. However, for the spring balance, the undirected control of the aircraft was abnormal and it might influence the quality opinion of the pilot on the handling quality of the aircraft. The load sensor on the control force indication glove must be improved. The reliability of the FlexiForce indicator also should be improved. Keywords-Control Force; Aircraft Quick Evaluation; Handling Quality; Flight test}, booktitle={Proceedings of the 2nd International Conference on Computer Application and System Modeling}, publisher={Atlantis Press}, author={Zhang, Dawei and Chen, Mingtai and Mi, Yi and Liu, Chaoqiang}, year={2012}, month={Aug} }