scholarly journals A method for rapid generation of 3D infrared radiation intensity field of engine exhaust plume

2020 ◽  
Author(s):  
Bao Xingdong ◽  
Yu Xilong ◽  
Wang Zhenhua ◽  
Mao Hongxia ◽  
Xiao Zhihe
Keyword(s):  
Radiation Intensity ◽  
Infrared Radiation ◽  
Engine Exhaust ◽  
Exhaust Plume ◽  
Intensity Field ◽  
Rapid Generation

Numerical evaluation of the exhaust-direction effects on plume flow and helicopter infrared radiation under hover and cruise statuses

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Zongyao Yang ◽  
Yong Shan ◽  
Jingzhou Zhang
Keyword(s):  
Radiation Intensity ◽  
Infrared Radiation ◽  
Design Methodology ◽  
Main Rotor ◽  
Content Type ◽  
Exhaust Plume ◽  
Ir Signature ◽  
Plume Flow ◽  
The Impact ◽  
Rotational Direction

Purpose This study aims to investigate the effects of exhaust direction on exhaust plume and helicopter infrared radiation in hover and cruise status. Design/methodology/approach Four exhaust modes are concerned, and the external flow field and fuselage temperature field are calculated by numerical simulation. The infrared radiation intensity distributions of the four models in hovering and cruising states are computed by the ray-tracing method. Findings Under the hover status, the exhaust plume is deflected to flow downward after it exhausts from the nozzle exit, upon the impact of the main-rotor downwash. Besides, the exhaust plume shows a “swirling” movement following the main-rotor rotational direction. The forward-flight flow helps prevent the hot exhaust plume from a collision with the helicopter fuselage generally for the cruise status. In general, the oblique-upward exhaust mode provides moderate infrared radiation intensities in all of the viewing directions, either under the hover or the cruise status. Compared with the hover status, the infrared radiation intensity distribution alters somewhat in cruise. Originality/value Illustrating the influences of exhaust direction on plume flow and helicopter infrared radiation and the differences of helicopter infrared radiation under hover and cruise statuses are identified. Finally, an appropriate exhaust mode is proposed to provide a better IR signature distribution.

scholarly journals Computation on Infrared Radiation of Side Exhaust Plume under Spraying Water

2021 ◽  
Vol 2112 (1) ◽  
pp. 012002
Author(s):  
Zhongke Sun ◽  
Zhongwei Chen ◽  
Xiao Ma
Keyword(s):  
High Temperature ◽  
Radiation Intensity ◽  
Infrared Radiation ◽  
Concentration Field ◽  
Exhaust System ◽  
Band Model ◽  
Exhaust Pipe ◽  
Liquid Droplets ◽  
Ansys Fluent ◽  
Exhaust Plume

Abstract The high temperature plume of ships has obvious infrared radiation feature. Spraying water-liquid droplets in side exhaust system can effectively reduce the high temperature of the tail gas to reduce the infrared radiation of the exhaust plume. In this paper, ANSYS Fluent is used to establish the concentration field and temperature field of the side exhaust plume atter spraying water-liquid droplets. And the statistic narrow band model (Malkmus model) and the C-G approximation method are used to calculate the infrared radiation intensity of the exhaust plume in the normal direction of the exhaust outlet from 3 to 5 μm on this basis. The final results show that spraying water-liquid droplets in side exhaust pipe can reduce the infrared radiation of the side exhaust plume from 3 to 5um by 88.9%% compared with the initial intensity; when the water flow reaches 0.7kg/s, infrared radiation intensity remains unchanged.

Thrust Measurements using Acoustic Sensing on a Turbofan Engine Exhaust Plume

2021 ◽  
Author(s):  
John Gillespie ◽  
Kevin T. Lowe ◽  
Wing Ng ◽  
Loren Crook ◽  
Victor Oechsle
Keyword(s):  
Engine Exhaust ◽  
Turbofan Engine ◽  
Acoustic Sensing ◽  
Exhaust Plume

scholarly journals Analysis of Infrared Radiation Intensity by Water-Mist Spraying in Ship Exhaust System

2021 ◽  
Vol 2112 (1) ◽  
pp. 012019
Author(s):  
Zhongke Sun ◽  
Zhen Wang ◽  
Zhongwei Chen ◽  
Zhihua Liu ◽  
Mo Liu ◽  
...  
Keyword(s):  
Radiation Intensity ◽  
Infrared Radiation ◽  
Exhaust System ◽  
Water Mist ◽  
Mist Cooling

Abstract The infrared radiation intensity in 3~5μm of conventional ship exhaust system are so severe [1] that can be easily captured by detector. Therefore, it’s necessary to take measure like spraying water mist to decrease temperature of exhaust system in order to decrease infrared radiation intensity. In this paper, the calculation of infrared radiation intensity of conventional ship exhaust system with water-mist spraying will be given. The results show that the average and maximum infrared radiation intensity of the exhaust system can be reduced by 90.3% and 95.7% after water mist cooling.

Study of Tunnel Water Detection through Infrared Acquisition Technology Based on 3D Trend Analysis

2013 ◽  
Vol 838-841 ◽  
pp. 1370-1380
Author(s):  
Shu Hao Zhang ◽  
Ya Wei Wang
Keyword(s):  
Trend Analysis ◽  
Radiation Field ◽  
Radiation Intensity ◽  
Infrared Radiation ◽  
Tunnel Construction ◽  
Water Detection ◽  
Visualization Software ◽  
Comparison And Analysis

The study discusses a revised method of water detection through infrared acquisition technology. In the case of Xianghe tunnel construction, the authors built 3D infrared radiation field functions through 3D trend analysis. The separately calculated radiation intensity trend values and outliers were processed by the visualization software, Voxler, and transformed into 3D distribution graphs for further comparison and analysis. The result indicates that the technique and method applied in this article successfully eliminate the random interference and realize the detection of aquifer.

Influence of Afterburning on Infrared Radiation of Liquid Rocket Exhaust Plume

2013 ◽  
Vol 42 (4) ◽  
pp. 480-485
Author(s):  
刘尊洋 LIU Zun-yang ◽  
邵立 SHAO Li ◽  
汪亚夫 WANG Ya-fu ◽  
孙晓泉 SUN Xiao-quan
Keyword(s):  
Infrared Radiation ◽  
Exhaust Plume ◽  
Liquid Rocket ◽  
Rocket Exhaust

scholarly journals Micro-Motion Dynamics and Shape Parameters Estimation Based on an Infrared Signature Model of Spatial Targets

Electronics ◽  
2019 ◽  
Vol 8 (7) ◽  
pp. 755 ◽  
Author(s):  
Dongya Wu ◽  
Huanzhang Lu ◽  
Bendong Zhao ◽  
Junliang Liu ◽  
Ming Zhao
Keyword(s):  
Radiation Intensity ◽  
Infrared Radiation ◽  
Estimation Method ◽  
Optimization Techniques ◽  
Parameters Estimation ◽  
Geometrical Shape ◽  
Infrared Signature ◽  
Micro Motion ◽  
Periodic Fluctuations ◽  
Motion Dynamics

Infrared imaging is widely applied in the discrimination of spatial targets. Extracting distinguishable features from the infrared signature of spatial targets is an important premise for this task. When a target in outer space experiences micro-motion, it causes periodic fluctuations in the observed infrared radiation intensity signature. Periodic fluctuations can reflect some potential factors of the received data, such as structure, dynamics, etc., and provide possible ways to analyze the signature. The purpose of this paper is to estimate the micro-motion dynamics and geometry parameters from the observed infrared radiation intensity signature. To this end, we have studied the signal model of the infrared radiation intensity signature, conducted the geometry and micro-motion models of the target, and we proposed a joint parameter estimation method based on optimization techniques. After analyzing the estimation results, we testified that the parameters of micro-motion and geometrical shape of the spatial target can be effectively estimated by our estimation method.

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