• Title/Summary/Keyword: 적외선 신호해석

Search Result 44, Processing Time 0.04 seconds

A Study on the Effect of Engine Nozzle Configuration on the Plume IR Signature (엔진 노즐 형상이 Plume 적외선 신호에 미치는 영향에 관한 연구)

  • An, Sung-Yong;Kim, Won-Cheol;Oh, Seong-Hwan
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.40 no.8
    • /
    • pp.688-694
    • /
    • 2012
  • A study on the effect of engine nozzle configuration on the engine plume Infra-red (IR) signature characteristics is performed. Configuration design of an engine nozzle with high aspect ratio to reduce IR signature level and a cylindrical nozzle which is typically used for conventional aircraft which does not require IR signature reduction is performed. And CFD analysis for the two nozzles is performed to compare the flowfields characteristics of the two nozzles. Finally IR signature analysis for the two nozzles is accomplished to calculate the total intensity level at mid-wave infra-red and investigate the differences of IR signature characteristics between the two nozzles.

Effect of Flight Altitude on Minimal Infrared Signature of Combat Aircraft (고도 변화에 따른 전투기 적외선 신호 최소 조건 분석)

  • Nam, Juyeong;Chang, Injoong;Lee, Yongwoo;Kim, Jihyun;Cho, Hyung Hee
    • Journal of the Computational Structural Engineering Institute of Korea
    • /
    • v.33 no.6
    • /
    • pp.375-382
    • /
    • 2020
  • Owing to the rapid development of infrared guided weapon systems, the threat to aircraft survivability is constantly increasing, and research on infrared stealth technologies are being conducted to ensure aircraft survival. In this study, we analyze the minimum infrared signature of an aircraft according to its flight altitude by considering the characteristics of infrared guided missiles, which detect the contrast signature between the aircraft and background. We conducted computational fluid dynamics simulations for the convective coefficient, and heat transfer simulations were performed considering convection, conduction, and radiation for flight conditions. Thus, we obtained the surface temperature distribution of the aircraft and analyzed the aircraft infrared signature based on the flow characteristics around it. Furthermore, the optimum emissivity for the minimum infrared signature was derived, and the effect of the infrared signature was analyzed when this optimum emissivity was applied to the fuselage surface for each flight condition.

Thermal Signature Characteristics of Clothed Human Considering Thermoregulation Effects (체온 조절 작용을 고려한 의복 착용 시의 인체 열상신호 특성 분석)

  • Chang, Injoong;Bae, Ji-Yeul;Lee, Namkyu;Kwak, Hwykuen;Cho, Hyung Hee
    • Journal of the Computational Structural Engineering Institute of Korea
    • /
    • v.32 no.2
    • /
    • pp.109-116
    • /
    • 2019
  • Survivability of soldiers has been greatly threatened by the development of thermal observation device(TOD). Therefore, infrared, especially thermal, stealth technology is applied to combat suit to avoid detection from TOD. In this study, prior to the thermal camouflage performance evaluation of combat suit, thermal signature characteristic from clothed the human body was analyzed considering the realistic condition for human surface temperature compared to that from unclothed human body. To get the realistic surface temperature distribution of human, thermoregulation and multi-layer skin structure model is applied to the human model. Based on temperature distribution, surface diffuse radiance in thermal range is calculated and by assuming the background conditions, contrast radiance intensity(CRI) characteristic of human body is analyzed. By wearing clothing, the CRI between background and human body became reduced in low emissive background but in high emissive background, the contrast is much more prominent. Therefore, this issue should be considered in design process of thermal camouflage combat suit.

Numerical and Experimental Study on Infrared Signature of Solid Rocket Motor (고체로켓모터의 적외선 신호에 관한 수치적·실험적 연구)

  • Kim, Sangmin;Kim, Mintaek;Song, Soonho;Baek, Gookhyun;Yoon, Woongsup
    • Journal of the Korean Society of Propulsion Engineers
    • /
    • v.18 no.5
    • /
    • pp.62-69
    • /
    • 2014
  • Infrared signature of rocket plume plays an important role for detection, recognition, tracking and minimzing for low observability. Infrared signatures of rocket plume with reduced smoke propellant and smokeless propellant are measured. In order to estimate the infrared signature of rocket plume, CFD analysis for flow structure of plume is performed, and layered integration method for estimating of infrared signature is used. Numerical and experimental results were in good agreement. Both propellants had similar infrared signature. Strong peak at $4.3{\mu}m$ region in the experimental results is appeared due to experimental error arising from the calibration procedure.

Development of a Generalized Software for IR Image Generation and Analysis (적외선 영상 생성 및 분석을 위한 종합 소프트웨어 개발)

  • Han, Kuk-Il;Kim, Do-Hwi;Choi, Jun-Hyuk;Ha, Nam-Koo;Jang, Hyun-Sung;Kim, Tae-Kuk
    • KIISE Transactions on Computing Practices
    • /
    • v.23 no.3
    • /
    • pp.141-147
    • /
    • 2017
  • Recently there has been an increasing demand for developing a domestic software (S/W) for infrared signature generation to prevent technology leakage and match the domestic operating environment. In this study, we developed a S/W for infrared signature generation and presented its structures and functions for creating and analyzing the IR images of designated spectral bands. The proposed S/W generates IR images of an object through calculations of surface temperatures and IR signals including the self-emitted, surface reflected and path dependent radiances. Moreover, the proposed S/W includes the features of infrared threat analyses from the generated IR images including the infrared contrast radiant intensity (CRI), detection ranges or detection probability analyses, unlike the imported, commercial infrared signature generation S/W.

Analysis of Flow and Infrared Signature Characteristics according to UCAV Nozzle Shape (무인전투기 배기구 형상에 따른 유동 및 적외선 신호 특성 분석)

  • Noh, Sooyoung;Bae, Ji-Yeul;Kim, Jihyuk;Nam, Juyeong;Jo, Hana;Cho, Hyung Hee
    • Journal of the Korean Society of Propulsion Engineers
    • /
    • v.23 no.5
    • /
    • pp.27-35
    • /
    • 2019
  • Stealth technology is a technique to avoid detection from detectors such as radar and infrared seekers. In particular, detection by infrared signature is more threatening because infrared missiles detect heat from the aircraft itself. Therefore, infrared stealth technology is essential for ensuring the survival of aircraft and unmanned combat aerial vehicles (UCAV). In this study, we analyzed aerodynamic and infrared stealth performance in relation to UCAV nozzle design. Based on simulation results, a double serpentine nozzle was effective in reducing the infrared signature because it could shield high-temperature components in the engine. In addition, we observed that the infrared signature was reduced at the turning position of the duct located at the rear part of the double serpentine nozzle.

Three-Dimensional Conjugate Heat Transfer Analysis for Infrared Target Modeling (적외선 표적 모델링을 위한 3차원 복합 열해석 기법 연구)

  • Jang, Hyunsung;Ha, Namkoo;Lee, Seungha;Choi, Taekyu;Kim, Minah
    • Journal of KIISE
    • /
    • v.44 no.4
    • /
    • pp.411-416
    • /
    • 2017
  • The spectral radiance received by an infrared (IR) sensor is mainly influenced by the surface temperature of the target itself. Therefore, the precise temperature prediction is important for generating an IR target image. In this paper, we implement the combined three-dimensional surface temperature prediction module against target attitudes, environments and properties of a material for generating a realistic IR signal. In order to verify the calculated surface temperature, we are using the well-known IR signature analysis software, OKTAL-SE and compare the result with that. In addition, IR signal modeling is performed using the result of the surface temperature through coupling with OKTAL-SE.

A Study on the Heat Flow Analysis of Infra-Red Signature Suppression System for Naval Ship (함정 적외선 신호저감 장치의 열 유동해석 연구)

  • Yoon, Seok-Tae;Cho, Yong-Jin;Ko, Dae-Eun
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.18 no.11
    • /
    • pp.740-746
    • /
    • 2017
  • Infrared signatures emitted from hot exhaust gases generated by the internal combustion engine and generator of naval ships and from the metal surfaces of the funnel have become the targets of infrared homing missiles, which is the main cause of a reduced survivability of naval ships. The infrared signatures from the exhaust gas and the metal surface of a funnel can be reduced by installing an infrared signature suppression (IRSS) system on a ship. The IRSS system consists of three parts: an eductor that generates turbulent flow of the exhaust gas, a mixing tube that mixes the exhaust gas with ambient air, and a diffuser that forms an air film using the pressure difference between the inside and outside air. As a basic study to develop an IRSS system using domestic technology, this study analyzed the model test conditions of an IRSS system developed by an overseas engineering company and installed on a domestic naval ship, and a numerical heat-flow analysis was conducted based on the results of the aforementioned analysis. Numerical heat-flow analysis was performed using a commercial numerical-analysis application, and various turbulence models were considered. As a result, the temperature and velocity of the exhaust gas at the educator inlet and diffuser outlet and that of the metal surface of the diffuser were measured, and found to agree well with the measurement results of the model test.

Infrared Signature Analysis on Armored Vehicle Applied with Emissivity Controlled Structure (장갑 차량의 방사율 제어구조 적용에 따른 적외선 신호 분석)

  • Kim, Taeil;Kim, Taehwan;Bae, Ji-Yeul;Jung, Daeyoon;Cho, Hyung Hee
    • Journal of the Computational Structural Engineering Institute of Korea
    • /
    • v.30 no.2
    • /
    • pp.179-184
    • /
    • 2017
  • Due to rapid development of infrared guided weapon, survivability of armored vehicle is severely threatened. Hence, reduction of susceptibility by lowering infrared signature level is essential to enhance survivability of the vehicle. For this purpose, numerical analysis is conducted to analyze time and spatial characteristics of infrared signature of the vehicle when surface emissivity changes in this study. The analysis shows that the emissivity which produces minimum contrast radiant intensity is significantly altered by time and detecting position. Based on the result, it is concluded that the controlled structures which have different emissivity should be adopted at different region of the vehicle to effectively decrease infrared signature level.

The Design of an Infrared Transcutaneous Control Unit for Totally Implantable Middle Ear System (완전 이식형 인공중이를 위한 체외 및 체내 제어시스템 구현)

  • 정의성;강호경;박일용;윤영호;김민규;송병섭;원철호;조진호
    • Journal of the Institute of Electronics Engineers of Korea SC
    • /
    • v.41 no.5
    • /
    • pp.71-78
    • /
    • 2004
  • An infrared remote control-type transcutaneous control device using a $\mu$-processor is design for the totally implantable middle ear system. An infrared light transmission model for the tissue of skin was introduced and then a radiant intensity and the required current of the infrared light emitting diode(IR LED) driving circuit at transmission part were calculated for the external control device. And the transmission part generates IR signal by the system's own data protocol which prevents interferences from other infrared remote controls of the household appliances. The control part of the implanted device was designed to analyze functions of the received infrared(IR) signal that indicate the power ON/OFF and volume UP/DOWN. After the system is implemented, a data transmission experiments using 4 mm thickness of porcine skin were carried out. From the experiment, it was verified that the infrared control signal was transmitted to receiving module of the implemented system without any error.