Article
Engineering, Aerospace
Zunyang Liu, Qing Ye, Feng Ding, Ying Xu, Xu Han
Summary: This study found that afterburning significantly increases infrared radiation, but the enhancement effect diminishes with increasing altitude. The enhancement effect is more pronounced at altitudes below 20 km, while it decreases above 20 km due to the decrease in oxygen concentration in the atmosphere.
INTERNATIONAL JOURNAL OF AERONAUTICAL AND SPACE SCIENCES
(2021)
Article
Instruments & Instrumentation
Jinlu Li, Lu Bai, Jingyu Bai, Yueyuan Xu, Danmeng Zhang, Lixin Guo
Summary: This study develops an accurate model to study the infrared radiation of rocket plume. The model calculates narrow-band radiation properties using a correction function and simulates the plume reaction flow using a refined chemistry scheme. The results show that the composition of the propellant, flight altitude, and flight Mach number all have an effect on plume infrared radiation.
INFRARED PHYSICS & TECHNOLOGY
(2022)
Article
Engineering, Aerospace
Zongyao Yang, Jingzhou Zhang, Yong Shan
Summary: A numerical investigation studied the influence of exhaust angle on plume flow, surface temperature, and infrared radiation of helicopters. Results showed that varying exhaust angles affected heating effect, exhaust temperature, and infrared radiation intensity.
AEROSPACE SCIENCE AND TECHNOLOGY
(2021)
Article
Thermodynamics
Jinlu Li, Lu Bai, Ligong Zhang, Jingyu Bai, Yueyuan Xu, Lixin Guo
Summary: Accurate modeling of rocket exhaust plumes' infrared spectral radiation is crucial in the aerospace field. The improved statistical-narrow-band (SNB) model can better adapt to the heterogeneous temperature and concentration fields of plumes, resulting in higher modeling accuracy at the spectral level. The model has been used to investigate the rocket plume spectral radiation during the booster phase, providing valuable insights for the development of the space-based infrared early warning system in the booster phase interception (BPI).
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2023)
Article
Engineering, Aerospace
Zongyao Yang, Jingzhou Zhang, Yong Shan
Summary: This study numerically investigated the effects of forward-flight speed on the exhaust plume flow and infrared radiation of an integrating infrared suppressor (IRS)-integrating helicopter. The results show that the interaction between forward-flight flow and downwash flow alters the exhaust plume development and the internal flow inside the IRS-integrating rear fuselage, and the influence of forward-flight speed on the overall infrared radiation intensity is complex due to the interaction between forward-flight flow and downwash flow.
CHINESE JOURNAL OF AERONAUTICS
(2022)
Article
Engineering, Aerospace
Zongyao Yang, Yong Shan, Jingzhou Zhang
Summary: The study investigates the effects of exhaust direction on exhaust plume and helicopter infrared radiation in hover and cruise status through numerical simulations and ray-tracing methods. Findings show that exhaust plume behavior is influenced by main-rotor downwash in hover, while forward-flight flow helps prevent collisions with the helicopter fuselage in cruise. The oblique-upward exhaust mode provides moderate infrared radiation intensities in all viewing directions, proving to be a suitable choice for both hover and cruise statuses.
AIRCRAFT ENGINEERING AND AEROSPACE TECHNOLOGY
(2021)
Article
Computer Science, Information Systems
Qinglin Niu, Wenqiang Gao, Yiqiang Sun, Shikui Dong
Summary: The study found that increasing the angle of attack shortened the scale and afterburning region of the rocket exhaust plumes, but the peak temperature remained relatively constant. With a higher angle of attack, the high-temperature region and Mach cells were compressed into a smaller domain.
Article
Chemistry, Physical
Juqi Zhang, Hong Qi, Donghang Jiang, Baohai Gao, Mingjian He, Yatao Ren, Kefu Li
Summary: This study investigates the integrated IR characteristics of aircraft, including the interaction between skin and exhaust plume, and obtains the IR intensity distributions at different Mach numbers. The results provide guidance for better detection and identification of typical flight targets.
Article
Thermodynamics
Rui Gu, Mingbo Sun, Peibo Li, Zun Cai, Yizhi Yao
Summary: The study of the thrust performance of rocket-based combined-cycle engines in ejector mode utilized a novel experimental facility, which provided acceptable test precision and a small difference in thrust between the test and simulation.
APPLIED THERMAL ENGINEERING
(2021)
Article
Thermodynamics
M. S. Yasar, G. Ozen, N. Selcuk, G. Kulah
Summary: This study investigates the influence of simplifying assumptions on the thermal radiation characteristics of rocket plumes. The results show that using mean diameters, temperature-independent optical properties, and gray optical properties can provide reasonably accurate predictions of radiative heat transfer.
COMBUSTION SCIENCE AND TECHNOLOGY
(2023)
Article
Engineering, Mechanical
Xiaojuan Shi, Xin Wei, Honghu Ji
Summary: This paper investigates the flow fields and infrared signatures of a turbofan engine axisymmetric exhaust system with and without afterburning. The results show that afterburning significantly increases thrust and infrared radiation of the exhaust system, with the plume being the main source of infrared radiation.
JOURNAL OF ENGINEERING FOR GAS TURBINES AND POWER-TRANSACTIONS OF THE ASME
(2023)
Article
Engineering, Multidisciplinary
Zhitan Zhou, Yiyin Bao, Peijie Sun, Guigao Le
Summary: The study investigates the afterburning effect on the thermal environment of rocket engine exhaust plume through numerical simulations, finding that the afterburning reactions have little impact on the Mach number exhaust flow, but significantly increase the temperature of the mixing layer. The afterburning effect reduces with increases in flight altitude.
ENGINEERING APPLICATIONS OF COMPUTATIONAL FLUID MECHANICS
(2021)
Article
Engineering, Aerospace
Zhitan Zhou, Limin Wang, Yiqing Li, Shuaixing Feng, Xiangyu Ding
Summary: The uplift angle of a deflector plays a crucial role in improving the thermal environment during rocket launches. Using a hybrid RANS/LES turbulence model and finite-rate chemical kinetics model, the researchers established an impingement model to investigate the effect of uplift angles on the thermal environment. The results showed that different uplift angles could significantly improve the thermal environment of the deflector, with a 6-degree uplift angle achieving the best guiding performance and reducing peak temperatures by 5.55% and 9.59% on the symmetry plane and deflector surface, respectively. This study provides valuable guidance for deflector system design.
ADVANCES IN SPACE RESEARCH
(2023)
Article
Engineering, Multidisciplinary
Zhi-Tan Zhou, Chang-Fang Zhao, Chen-Yu Lu, Gui-Gao Le
Summary: This paper investigates the flow field of a four-engine liquid rocket during launch phase, analyzing the impact of two different flame deflectors on the exhaust plume. The results show that cone-shaped flame deflectors outperform wedge-shaped ones in guiding exhaust gas, with higher pressure and temperature levels on the surface.
DEFENCE TECHNOLOGY
(2021)
Article
Engineering, Multidisciplinary
Zhitan Zhou, Yiying Bao, Peijie Sun, Yiqing Li
Summary: In this study, the cooling effects of a water spray system with different injection velocities on the thermal loads caused by the exhaust jet of a rocket engine were analyzed through numerical simulation. The results showed that the water cooling system effectively protected the launch platform from thermal loads. Additionally, the study highlighted the impact of high water injection velocities on the guiding performance of the deflector.
ENGINEERING APPLICATIONS OF COMPUTATIONAL FLUID MECHANICS
(2022)
Article
Thermodynamics
Mahsa Taghavi, Swapnil Sharma, Vemuri Balakotaiah
Summary: This study investigates the natural convection effects in the insulation layers of spherical storage tanks and their impact on the tanks' performance. The permeability and Rayleigh number of the insulation material are considered as key factors. The results show that as the Rayleigh number increases, new convective cells emerge and cause the cold boundary to approach the external hot boundary. In the case of large temperature differences, multiple solutions may coexist.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Jinyang Xu, Fangjun Hong, Chaoyang Zhang
Summary: This study introduces a self-induced jet impingement device for enhancing pool boiling performance in high power electronic cooling. Through visualization and parametric investigations, the effects of this device on pool boiling performance are studied, revealing the promotion of additional liquid supply and vapor exhausting. The flow rate of the liquid jet is found to positively impact boiling performance.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Wenchao Ke, Yuan Liu, Fissha Biruke Teshome, Zhi Zeng
Summary: Underwater wet laser welding (UWLW) is a promising and labor-saving repair technique. A thermal multi-phase flow model was developed to study the heat transfer, fluid dynamics, and phase transitions during UWLW. The results show that UWLW creates a water keyhole, making the welding environment similar to in air laser welding.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Xingrong Lian, Lin Tian, Zengyao Li, Xinpeng Zhao
Summary: This study investigates the heat transfer mechanisms in natural fiber-derived porous structures and finds that thermal radiation has a significant impact on the thermal conductivity in low-density regions, while natural convection rarely occurs. Insulation materials derived from micron-sized natural fibers can achieve minimum thermal conductivity at specific densities. Strategies to lower the thermal conductivity include increasing porosity and incorporating nanoscale pores using nanosize fibers.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Yasir A. Malik, Kilian Koebschall, Stephan Bansmer, Cameron Tropea, Jeanette Hussong, Philippe Villedieu
Summary: Ice crystal icing is a significant hazard in aviation, and accurate modeling of sticking efficiency is essential. In this study, icing wind tunnel experiments were conducted to quantify the volumetric liquid water fraction, sticking efficiency, and maximum thickness of ice layers. Two measurement techniques, calorimetry and capacitive measurements, were used to measure the liquid water content and distribution in the ice layers. The experiments showed that increasing wet bulb temperatures and substrate heat flux significantly increased sticking efficiency and maximum ice layer thickness.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Jinqi Hu, Tongtong Geng, Kun Wang, Yuanhong Fan, Chunhua Min, Hsien Chin Su
Summary: This study experimentally examined the heat dissipation of vibrating fans and demonstrated its inherent mechanism through numerical simulation. The results showed that the flow fields induced by the vibrating blades exhibited pulsating features and formed large-scale and small-scale vortical structures, significantly improving heat dissipation. The study also identified the impacts of different blade structures and developed a trapezoidal-folding blade, which effectively reduced the maximum temperature of the heat source and alleviated high-temperature failure crisis.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Dan-Dan Su, Xiao-Bin Li, Hong-Na Zhang, Feng-Chen Li
Summary: The boiling heat transfer of low-boiling-point working fluid is a common heat dissipation technology in electronic equipment cooling. This study analyzed the interfacial boiling behavior of R134a under different conditions and found that factors such as the initial thickness of the liquid film, solid-liquid interaction force, and initial temperature significantly affect the boiling mode and thermal resistance.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Jinyi Wu, Dongke Sun, Wei Chen, Zhenhua Chai
Summary: A unified lattice Boltzmann-phase field scheme is proposed to simulate dendrite growth of binary alloys in the presence of melt convection. The effects of various factors on the growth are investigated numerically, and the model is validated through comparisons and examinations.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Shaokun Ge, Ya Ni, Fubao Zhou, Wangzhaonan Shen, Jia Li, Fengqi Guo, Bobo Shi
Summary: This study investigated the temperature distribution of main cables in a suspension bridge during fire scenarios and proposed a prediction model for the maximum temperature of cables in different lane fires. The results showed that vehicle fires in the emergency lane posed a greater thermal threat to the cables.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Shuang-Ying Wu, Shi-Yao Zhou, Lan Xiao, Jia Luo
Summary: This paper investigates the two-phase flow and heat transfer characteristics of low-velocity jet impacting on a cylindrical surface. The study reveals that the heat transfer regimes are non-phase transition and nucleate boiling with the increase of heat transfer rate. The effects of jet impact height and outlet velocity on local surface temperatures are pronounced at the non-phase transition stage. The growth rates of heat transfer rate and liquid loss rate increase significantly from the non-phase transition to nucleate boiling stage.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Emad Hasani Malekshah, Wlodzimierz Wlodzimierz, Miros law Majkut
Summary: Cavitation has significant practical importance and can be controlled by air injection. This study investigates the natural to ventilated cavitation process around a hydrofoil through numerical and experimental methods. The results show that the location and rate of air injection have a meaningful impact on the characteristics of cavitation.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Feriel Yahiat, Pascale Bouvier, Antoine Beauvillier, Serge Russeil, Christophe Andre, Daniel Bougeard
Summary: This study explores the enhancement of mixing performance in laminar flow equipment by investigating the generation of chaotic advection using wall deformations in annular geometries. The findings demonstrate that the combined geometry can achieve perfect mixing at various Reynolds numbers.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Hui He, Ning Lyu, Caihua Liang, Feng Wang, Xiaosong Zhang
Summary: This study investigates the condensation, frosting, and defrosting processes on superhydrophobic surfaces with millimeter-scale structures. The results reveal that the structures can influence the growth and removal of frost crystals, with the bottom grooves creating a frost-free zone and conical edges promoting higher frost crystal heights. Two effective methods for defrosting are observed: hand-lifting the groove and airfoil retraction contraction on protruding structures. This research provides valuable insights into frost formation and defrosting on millimeter-structured superhydrophobic surfaces, with potential applications in anti-frost engineering.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Thiwanka Arepolage, Christophe Verdy, Thibaut Sylvestre, Aymeric Leray, Sebastien Euphrasie
Summary: This study developed two thermal concentrators, one with a 2D design of uniform thickness and another with a 3D design, using the coordinate transformation technique and metamaterials. By structuring the thermal conductor, the desired local density-heat capacity product and anisotropic thermal conductivities were achieved. The homogenized thermal conductivities were obtained from finite element simulations and cylindrical symmetry consideration. A 3D concentrator was fabricated using 3D metal printing and characterized using a thermal camera. Compared to devices that solely consider anisotropic conductivities, the time evolution characteristics of the metadevice designed with coordinate transformation were closer to those of an ideal concentrator.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Liangyuan Cheng, Qingyang Wang, Jinliang Xu
Summary: In this study, we investigated the supercritical heat transfer of CO2 in a horizontal tube with a diameter of 10.0 mm, covering a wide range of pressures, mass fluxes, and heat fluxes. The study revealed a non-monotonic increase in wall temperatures along the flow direction and observed both positive and negative wall temperature differences between the bottom and top tube. The findings were explained by the thermal conduction in the solid wall interacting with the stratified-wavy flow in the tube.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)