Numerical research of perspective technical solutions for thermal protection of surfaces flowed by high-speed dispersed flows

2019 ◽  
Author(s):  
Vladislav N. Kovalnogov ◽  
Ruslan V. Fedorov ◽  
Larisa V. Khakhaleva ◽  
Andrei V. Chukalin ◽  
Aleksandr N. Zolotov
Keyword(s):  
High Speed ◽  
Thermal Protection ◽  
Numerical Research ◽  
Technical Solutions ◽  
Dispersed Flows

scholarly journals Recent advancements in shape optimization of aero spiked high speed re-entry vehicle using CFD

2018 ◽  
Vol 172 ◽  
pp. 01007
Author(s):  
Harish Panjagala ◽  
E L N Rohit Madhukar ◽  
I Ravi Kiran
Keyword(s):  
High Speed ◽  
Structural Integrity ◽  
Elevated Temperatures ◽  
Thermal Protection ◽  
Space Vehicle ◽  
Protection Systems ◽  
Ultimate Outcome ◽  
Increasing Demand ◽  
Space Activities ◽  
Intense Heat

Due to increasing demand of High Speed Re-entry vehicles for Space activities within the world, a serious issue associated with the method of deceleration down a vehicle is by the intense heat generated because of development of stronger shocks at the nose. The price of thermal protection systems (TPS) to cut back the warmth generated by the return vehicles is extremely high. In this paper, the ultimate outcome is to cut back the aero heating which is achieved by introducing a spike at frontal region of the nose. Additionally, this spike avoids the deterioration and preserves the structural integrity of space vehicle over elevated temperatures. Further, four totally different geometries of tip specifically Blunt, Slender, Snap and Pan for the aerospike has been introduced and their impact on performance is evaluated and compared with the vehicle having TPS. Hence, usage of aerospike in return vehicles is the most successful and economical over different protection system.

scholarly journals The Concept of Development and Implementation of High-Speed Transport

2020 ◽  
Vol 18 (1) ◽  
pp. 58-72
Author(s):  
V. M. Alexeev ◽  
A. V. Vaganov ◽  
M. V. Katina
Keyword(s):  
High Speed ◽  
Magnetic Levitation ◽  
Transport Systems ◽  
Rolling Stock ◽  
Design Elements ◽  
Safety Issues ◽  
Current Collection ◽  
High Speeds ◽  
Technical Solutions ◽  
Original Approach

The article discusses the issues of implementation and organization of high-speed transport. The objective of the article is to consider possible options for implementing highspeed (HS) motion systems using the principle of magnetic levitation, which will ensure high speeds for delivery of goods and carrying people over long distances. To achieve this objective, it is necessary to develop an engine and technical solutions for design of HS rolling stock, make decisions on energy supply infrastructure and the HS track, address safety issues and new control systems considering the state of the infrastructure and its design elements. The article discusses several options for implementation of high-speed transport systems, differing in the power supply system, current collection and track based on the magnetic levitation approach. An original approach is proposed in implementation of magnetic levitation transport using the technology of electromagnetic guns designed to implement traction forces of a magnetic levitation vehicle. The advantage of this approach is that it opens the possibility of maneuvering for the vehicle while driving. This allows to abandon switch turnouts, now significantly limiting the use of magnetic levitation transport. A mathematical model describing interaction of an electromagnetic gun and supermagnets located on the track is considered. In constructing the model, methods of the theory of electromagnetic field and interaction of magnetic bodies were used, and when constructing a model of interaction of rolling stock with a magnetic track, methods of mathematical algebra and the Cauchy theorem were used. The article discusses various principles of organization of movement using the magnetic levitation for urban, suburban, and intercity transport.

scholarly journals Study on the thermal protection performance of superalloy honeycomb panels in high-speed thermal shock environments

2014 ◽  
Vol 4 (2) ◽  
pp. 021004 ◽  
Author(s):  
Dafang Wu ◽  
Anfeng Zhou ◽  
Liming Zheng ◽  
Bing Pan ◽  
Yuewu Wang
Keyword(s):  
Thermal Shock ◽  
High Speed ◽  
Thermal Protection

scholarly journals Research on Thermal Insulation Performance of Lightweight Thermal Protection Materials for High Speed Aircraft under Different Boundary Conditions

2018 ◽  
Vol 179 ◽  
pp. 02001
Author(s):  
Feng Wang ◽  
Dafang Wu ◽  
Haoyuan Ren
Keyword(s):  
Boundary Conditions ◽  
Thermal Insulation ◽  
High Speed ◽  
Thermal Protection ◽  
Different Boundary Conditions ◽  
Flight Vehicles ◽  
Calculation Results ◽  
Different Temperatures ◽  
Insulation Performance

The determination of thermal insulation performance of thermal protection materials or structures is an indispensable and important step in the safety design of high speed flight vehicles. To obtain the temperature difference of the radiating surface for plate specimens under three different boundary conditions in heat insulation experiments (the specimens were placed either vertically or horizontally with the radiating surface facing down or horizontally with the radiating surface facing up), three thermal test setups were established to test the thermal insulation performance of light-weight ceramic specimens at different temperatures. The results show that the radiating surface temperature was the highest when the specimen was placed horizontally with the radiating surface facing down, while it was the lowest when the specimen was placed horizontally with the radiating surface facing up.The numerical calculation results agreed very well with the experimental ones, confirming the credibility and accuracy of the experimental results. The different thermal insulation performances of the plate specimens obtained under three different boundary conditions will provide important guidance for designers in the design of thermal protection systems for large cabins of high speed flight vehicles.

Influences of Thermal Loads on Nonlinear Response of Thin-Walled Structures in Thermo-Acoustic Environment

2011 ◽  
Vol 105-107 ◽  
pp. 220-226 ◽  
Author(s):  
Yun Dong Sha ◽  
Zhi Jun Gao ◽  
Fei Xu
Keyword(s):  
High Speed ◽  
Nonlinear Response ◽  
Large Deflection ◽  
Thermal Protection ◽  
Thermal Loads ◽  
Acoustic Response ◽  
Restoring Force ◽  
Acoustic Environment ◽  
Thin Walled Structures ◽  
Thin Walled

Thin-walled structures of future hypersonic flight vehicles will encounter complex loadings and exhibit obvious nonlinear responses. The thermal loads from high speed flow or engine jet flow can cause thermal buckling of thin-walled structures, such as Thermal Protection System (TPS). If the structures are loaded with intense acoustic loads simultaneously, large deflection nonlinear response, including snap-through, can be induced. Snap-through will give rise to large amplitude stress cycles and non-zero mean stress, which can lessen the fatigue life markedly. Starting from Hooker’s Law with thermal components, the large deflection governing equations of motion for simply-supported plate under thermo-acoustic loadings are derived. The partial differential equation (PDE) of motion which is difficult to solve is then transformed with Galerkin’s method to the system of ordinary differential equations (ODE) under modal coordinates. The displacement responses under different combinations of temperature increments and sound pressure levels are calculated by employing Runge-Kutta method. Typical thermo-acoustic responses are predicted: 1) random vibration around pre-buckled equilibrium position, 2) persistent snap-through between post-buckled positions, 3) intermittent snap-through, 4) vibration around one of the two post-buckled positions. By dividing the restoring force term in the equation into linear term and nonlinear one, the evolutions of each term are obtained to illustrate the mechanism of thermo-acoustic response and the contributions of each force, including shear force, thermal force and membrane force. Thus a further insight into thermo-acoustic response has been achieved.

Comparative Assessment of Thermal Protective Characteristics of Metal and Ceramic Shields of Flow Paths of High-Temperature Gas Dynamic Facilities

2020 ◽  
pp. 52-75
Author(s):  
V.A. Tovstonog
Keyword(s):  
High Temperature ◽  
High Speed ◽  
Thermal Protection ◽  
Modern Technology ◽  
Flow Path ◽  
Comparative Assessment ◽  
Working Fluid ◽  
Gas Dynamic ◽  
Heat Shields ◽  
Ramjet Engines

In modern technology, gas dynamic facilities with a flow path of a high-temperature working fluid are widely used. Their effectiveness largely depends on the maximum achievable temperature, which is to a great extent determined by the heat resistance of structural materials and thermal protection systems of the most heat-stressed structural units. Most often, mass transfer thermal protection methods using the coolant of fuel components are used in such plants. However, in some gas dynamic facilities, such as high-speed ramjet engines, the use of such methods is only sufficient to maintain an acceptable temperature level for the elements of the flow path itself. As for the thermal protection of the enclosing structural elements which are adjacent to the path, it can be provided with either uncooled screens or heat-insulating linings. The study gives a comparative assessment of the temperature regime and characteristics of alternative types of heat shields

A New Micro Turbo-Machinery Test Facility

2010 ◽  
Author(s):  
Chen Xia ◽  
Guoping Huang ◽  
Jie Chen
Keyword(s):  
Mass Flow ◽  
High Speed ◽  
Modular Design ◽  
Thermal Protection ◽  
Dynamic Pressure ◽  
Pressure Sensors ◽  
Test Facility ◽  
Inlet Temperature ◽  
Test Bed ◽  
Turbo Machinery

The design and construction of a new test facility of micro turbo-machinery are presented for micro centrifugal compressors and radial turbines. The bed can be used for the full speed compressor test and the long duration hot turbine test. In order to adjust the testing condition rapidly, all the regulations of operating state are completed automatically by the control system. The test bed can be used for testing impeller performance with a series of diameter from 55 to 180 mm as a result of the modular design. A thermal protection system is designed to avoid the heat distortion caused by the high inlet temperature of turbine which may exceeds 1100K and provide a proper experimental environment for the electronic components. A photoelectric torque transducer with an accuracy of 1% is designed to measure the torque of a rigid shaft at a high speed over 120000rpm, and the maximum shaft torque is 7.7 N·m. The pressure and temperature are measured by pressure probes and thermocouples. The dynamic pressure signal of the centrifugal compressor is monitored by dynamic pressure sensors. The V-cone pressure-difference mass-flow meters are used for measuring mass-flow. The maximum rotating speed is 125000rpm, and the mass flow adjusted by the electric control valves varies from 0.1 to 1.0 kg/sec. The maximum inlet total temperature of the turbine is 1180K.

Aerodynamic Heating Numerical Simulation of Terminal-Sensitive Projectile at Deceleration and Despinning Trajectory

2013 ◽  
Vol 376 ◽  
pp. 317-322
Author(s):  
Jun Zhang ◽  
Rong Zhong Liu ◽  
Rui Guo ◽  
Xiao Dong Ma
Keyword(s):  
Numerical Simulation ◽  
High Speed ◽  
Thermal Protection ◽  
Thermal Characteristics ◽  
Simulation Method ◽  
Aerodynamic Heating ◽  
Transient Temperature ◽  
Physical Parameters ◽  
Temperature Distributions ◽  
Infrared Signature

Aero-heating problem severely affects the performance of terminal-sensitive projectile (TSP) when projected out of the carrier capsule by the gunpowder gas at a high speed. In this paper, based on the typical ballistic data and airflow physical parameters at deceleration and despinning trajectory, the aerodynamic thermal characteristics of a TSP was simulated by Fluent, and the transient temperature distributions were obtained under the different flying conditions. Finally, we got stagnation temperatures by the numerical simulations which were similar to those by the engineering evaluation, and demonstrate the effectiveness of the simulation method. The results are valuable to the research of thermal protection and infrared signature of TSP.

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