Papers by Keyword: ICF

Abstract: Nowadays, one of the fastest growing technique is an Insulated Concrete Form (ICF). It has advantages like cost-effective, less maintenance, soundproof, energy-efficient, waterproof and disaster-resistant. ICF wall panels are made by interlocking Fibre Cement Board (FCB) sheet which poured in placed concrete. In this study, the behaviour of the ICF wall panel under axial compression is examined with experimental and analytical methods. ICF wall panels cast with various thickness and dense FCB are tested under axial compression. ICF panels with 1.2gm³/cm dense FCB with changing width of 6mm and 10mm were casted for experimental analysis. The experiments were carried out in an universal testing machine with the capacity of 600 kN. The maximum peak load of 540 kN is observed in FCB of 10mm thick and the maximum displacement of 13mm is observed in FCB80 at the peak load. An analytical investigation is carried with Euler’s crippling load equation and an average variation of 12% is observed between analytical and experimental results. It is concluded that the ICF system of construction provides desirable plastic behaviour against axial compressive loading. Hence ICF is recommended for construction to get the maximum benefits of the wall while it reaches ultimate strain.

Abstract: The size of pulse compression gratings (PCG) is very big in the ICF system, so we obtained a large size grating by mechanically stitching small caliber gratings. And we design the splicing mechanism to be a 5-DOF Parallel Mechanism with macro/micro dual feed drive control to meet the requirements of large travel, high precision, high stability and 5-DOF of the grating tiling. The macro-moving part is designed to be the 5PTS-1PPS parallel mechanism, using the Feed Mechanism of ballscrew with Stepper Motor Drive.The micro-moving part is designed to be 5TSP-1PPS parallel mechanism, using the feed mechanism of Flexure Hinge with Piezoelectric Ceramic Actuator. We derived control algorithm of parallel mechanism by the method of the Kinematics of parallel mechanism. We analyzed the systematic error and put forward the error correction method in order to improve the positioning accuracy. At last, we designed an optical detecting system to evaluate the feasibility of this scheme, the positioning accuracy and the Stability of parallel Splicing structure. The results showed that the mechanism performance can meet the requirements of grating tiling work.

Abstract: There are three subsystems in Microtarget-Automatic-Assembly System which is used in Inertial Confinement Fusion(ICF). It is microscopic image measurement subsystem,confocal probe measurement subsystem and three-dimensional motion subsystem. It is necessary to establish a unified coordinate system in order to interact information in three subsystems and provide accurate and reliable position and attitude information for micro-operating system.Each coordinate system and its errors are analyzed in this paper.In the end,the way to establish the unified coordinate system is given. It is proved that this subsystem meets the requirements for precision.

Abstract: The spatial temperature distribution in the target range of the ICF driver is one of the key factors, which affects the precision optical components and equipment for normal operation. Application of the basic theory of heat transfer, this paper has discussed the fluid motion mathematical model in ICF driver middle target range. With the aid of finite element analysis software FLUENT, the temperature Numerical Analysis Model has been established. In accordance with assuming the numerical simulation boundary condition, spatial temperature field distribution in the target range intermediate level has calculated. The results indicate that the target range intermediate level temperature field is uniform basically. The temperature fluctuation scope is in a tiny range around 23°C about in the entire space. Although the maximum gradient of temperature achieves 1.2°C in existence heat source region, it is in the range of temperature indicators. This indicates that the present HVAC system can satisfy the request. By analyzing, the results of numerical analysis are in good agreement with experimental results, because the error is only 0.2%.

Abstract: Influence of the cutter rake angle to the surface quality of crystal KDP is analyzed theoretically in this paper. Analysis result shows that the tension stress reaches minimum in the crystal KDP cutting region and optimal value of the surface quality is obtained as cutter rake angle is about -45°. Cutting experimental of different cutter rake angle is realized on the machine tool. Experimental results show that the surface roughness of the crystal KDP reach minimum (rms is 6.521nm, Ra is 5.151nm) as the cutter rake angle is about -45°, this experiment certifies the correctness of this theory analysis. Theory analysis and experimental results show that influence of the cutter rake angle to surface quality of the crystal KDP is very large, for ultra-precision machining of the crystal KDP, when large negative rake diamond cutter (-45°) is adopted, the super-smooth surface can be obtained.

Abstract: This paper describes a micro-target semiautomatic assembly system used in ICF. In the system two halves of a cylindrical gold hohlraum (1.6 mm long by 0.8 mm in diameter) and a microsphere capsule (about 0.2 mm in diameter) are assembled. CCD cameras are applied to monitor the process of closed loop assembly.