Semi-physical Simulation & Test System for Electromagnetic Wave Imaging

The process of converting a data structure or object state into a storable format is referred to as serialization. For the simulation of complex electromagnetic interference test environment, to evaluate the ability of the communication system, based on the semi physical simulation test environment, this paper presents a kind of instruction serialization mode based on TCP protocol as the data transmission and control scheme of multi device control, design and implementation of various types of equipment centralized monitoring framework for the realization of all kinds of network communications equipment and status data centralized testing and monitoring purposes, to achieve a data device management control process is accurate, real-time transmission.

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Physical Simulation Test on Temperature Field Distribution of Artificial Vertical Straight Multirow Freezing Inclined Shaft

Geofluids ◽

10.1155/2021/5574713 ◽

2021 ◽

Vol 2021 ◽

pp. 1-12

Author(s):

Jielong Sun ◽

Jianxi Ren

Keyword(s):

Temperature Field ◽

Field Distribution ◽

Wall Temperature ◽

Field Measurement ◽

Physical Simulation ◽

Three Dimensional ◽

Test System ◽

Simulation Test ◽

Temperature Field Distribution ◽

Frozen Sand

This study investigated the temperature field distribution of a freezing inclined shaft. Thus, a three-dimensional physical simulation test system was developed, and the system consists of six parts, which are simulation box and shaft model, loading system, freezing system, external environment simulation system, and data acquisition system. From the results of physical and mechanical property test of artificially frozen sand, in the range of 25°C to -20°C, the heat capacity of sand decreases first, then increases, decreases, and finally tends to be stable; the thermal conductivity of sand gradually increases and finally becomes stable; and the cohesion, internal friction angle, uniaxial compressive strength, and elastic modulus of artificially frozen sand all increase as the freezing temperature decreases. The three-dimensional physical simulation test and field measurement showed that the distance from the freezing pipe is the main factor affecting freezing wall temperature, and the closer to the freezing pipe, the faster the cooling rates. Comparison of theoretical calculation results and field measurement results shows that the calculation formula of freezing wall temperature with time of the inclined shaft can reflect the general law of freezing wall temperature cooling. Therefore, the 3D physical simulation test system is reliable and the test method is feasible.

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Physical Model Test of Artificial Freezing-Inclined Shaft

Advances in Civil Engineering ◽

10.1155/2021/6640722 ◽

2021 ◽

Vol 2021 ◽

pp. 1-11

Author(s):

Jielong Sun ◽

Xingzhou Chen ◽

Mingming Qiu ◽

Xueye Cao ◽

Shaojie Chen

Keyword(s):

Physical Model ◽

Physical Simulation ◽

Test System ◽

Physical Model Test ◽

Test Scheme ◽

Test Model ◽

Simulation Test ◽

Cooling Rates ◽

Artificial Freezing ◽

3D Physical Simulation

Based on the vertical straight artificial freezing engineering in Northern Shaanxi, a three-dimensional (3D) physical simulation test system was developed, consisting of six parts, which are simulation box, shaft model, loading system, freezing system, external environment simulation system, and data acquisition system. The physical model and actual test results show that the 3D physical simulation test system is reasonable and reliable. The test model results show that the distance from the freezing pipe significantly affects the freezing wall temperature. For the case of four adjacent, two adjacent tangential freezing, and two adjacent axial freezing pipes, the cooling rates were 1.37, 2.79, and 1.96°C/h, respectively. The field measurement showed that the proximity to the freezing pipe increases the cooling rates. The cooling rates of points 1k#, 2k#, and 3k# were 25.61, 25.32, and 25.35 mm/d, respectively. The increment rates of vertical and horizontal freezing pressures with temperature were 8.78 and 2.97 kPa/°C, respectively. Furthermore, the freezing pressure time fitting formula was given. The calculated results of temperature and freezing pressure are consistent with the measured results, indicating the reasonability and reliability of the 3D physical simulation test scheme of the artificial freezing-inclined shaft in this work.

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Ground Flutter Simulation Test Based on Reduced Order Modeling of Aerodynamics by CFD/CSD Coupling Method

International Journal of Applied Mechanics ◽

10.1142/s175882511950008x ◽

2019 ◽

Vol 11 (01) ◽

pp. 1950008

Author(s):

Binwen Wang ◽

Xueling Fan

Keyword(s):

Aerodynamic Force ◽

Test System ◽

Simulation Test ◽

Robust Controller ◽

Test Technique ◽

Reduced Order ◽

Aerodynamic Model ◽

Flutter Boundary ◽

Computational Fluid Dynamics Cfd ◽

Good Agreement

Flutter is an aeroelastic phenomenon that may cause severe damage to aircraft. Traditional flutter evaluation methods have many disadvantages (e.g., complex, costly and time-consuming) which could be overcome by ground flutter test technique. In this study, an unsteady aerodynamic model is obtained using computational fluid dynamics (CFD) code according to the procedure of frequency domain aerodynamic calculation. Then, the genetic algorithm (GA) method is adopted to optimize interpolation points for both excitation and response. Furthermore, the minimum-state method is utilized for rational fitting so as to establish an aerodynamic model in time domain. The aerodynamic force is simulated through exciters and the precision of simulation is guaranteed by multi-input and multi-output robust controller. Finally, ground flutter simulation test system is employed to acquire the flutter boundary through response under a range of air speeds. A good agreement is observed for both velocity and frequency of flutter between the test and modeling results.

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