Advanced Materials Research Vols. 631-632

Abstract: A novel planar extended doublet filter based on substrate Integrated waveguide cavity resonators was proposed for the first time. This filter consists of a main doublet with an additional resonator grown in one of the branches. The source and load are coupled to both branches of the doublet in order to generate two transmission zeros. By employing the combinational structure of the TE101-mode and TE102-mode of the SIW cavity resonators, the negative coupling coefficient required for the design of a single-layer cross-coupled SIW bandpass filter is implemented. The measurement results show the return loss of the implemented filter is above 13dB, the insertion loss is below 4.238dB with only 0.56% of the bandwidth.

Abstract: The coal mine refuge chamber is the necessary production of emergency system used in the underground coal mine. It can be installed conveniently and moved with the workplace. So it is more widely applied. The composition and basic performance requirements of coal mine refuge chamber were introduced in this paper. The performance of reinforcing ribs was done by finite element analysis software ANSYS Workbench and the performance optimization method of square tube reinforcing ribs thin plate was proposed. It can provide some reference for the design and performance research of refuge chamber bulkhead.

Abstract: This article has carried out systematic research on the multi-tooth meshing problem of involute internal gear pairs with small tooth number difference of stub gear. It firstly establishes the entity assembly model of internal gear pairs with precise tooth profile, then determines the number of multi-tooth meshing teeth pairs with finite element software and finally analyzes the main factors and reason affecting the number of meshing teeth pairs. In the range of tooth number of internal gear equal to 40-150, the conclusion is that when tooth number difference equal to 1 the number of effective meshing teeth pairs is 2-10,when tooth number difference equal to 5 the number of effective meshing teeth pairs is 2-8. The main factors affecting the number of meshing teeth pairs are tooth number and tooth number difference. The fewer tooth number is and the greater tooth number difference is, the fewer the number of meshing teeth pairs is. The reason is that when tooth number is obviously reduced or tooth number difference is obviously increased, the clearance of adjacent gear surface will be greatly increased, which will cause the decrease of the number of meshing teeth pairs. Within the normal value scope of modification coefficient difference of involute internal gear pairs with small tooth number difference, the influence of modification coefficient difference and modification coefficient is very small. When the torque increases, the number of effective contacting teech pairs will keep unchanged. The research in this article provides reference for the calculation of loading capacity of multi-tooth meshing of internal gear pairs with small tooth number difference of stub gear

Abstract: The internal combustion engine should be enlarged the cylinder diameter for the Power requirements. In order to ensure the engine to work normally, it is needed to compute the strength of the connecting rod. Through adopting ANSYS software, the three-dimensional computational model is constructed, and the stress analysis is carried out. We can learn the stress field of process of deformation. Through calculation the stress and strength of connecting rod are derived. Using the stress which was calculated from ANSYS we can decide the Safety of connecting rod. In general, the analysis is meaningful to optimize the design of connecting rod.

Abstract: In this paper, a calibration-free wavelength modulation model via tunable diode laser absorption spectroscopy was setup. The laser modulation characteristics, modulation depth, linear modulation amplitude and frequency shift, were measured for the model setup. The experimental results show that modulation depth and the linear intensity modulation amplitude have well linear fitting to the scan voltage. Based on the laser parameters, the calibration-free model can be used to infer the gas temperature.

Abstract: A streamer corona discharge plasma was used to assist a propane-jet flame. The nonequilibrium plasma was produced by a 10k Hz sinusoidal power source. The experimental results shows that a streamer corona was generated between the flame edge and the nozzle, and the use of the streamer corona plasma discharge resulted in significant increase in flame stability.

Abstract: his paper is based on image processing techniques, combined principle of Matrix CCD and image grabbing card , measured divergency angle of laser by focus spot method. In windows environment, using VC++ develop tools, achieved De-nosing and recognition of image and the measuring of laser divergency angle. A standard laser which of divergency angle is known is measured with focus spot proposed by the paper, the relative error ≦ 5%，which meets demand of test precision.

Abstract: The virtual prototype simulation of the underground pumping system can’t realize the timing analysis with the ground pumping unit system. In order to solve this problem, the simulation analysis model of the pumped well virtual prototype was established via the multibody dynamics simulation software Adams by analyzing the working characteristic of the sucker rod string. The simulation was in accordance with the dynamic indicator diagram which verifies the correctness of the simulation analysis model of the pumped well virtual prototype and also offers a new analysis method for the underground pump dianamograph and pumping unit balance, etc.

Abstract: Turbulent Prandtl number used in numerical simulation has effect on exact prediction of velocity and heat transferring with two dimensional buoyant mathematical models. Various Prandtl number values advised by experiments are used to study its effect on numerical results approaching to real ones with model under axisymmetric coordinate. It shows that axial velocities can’t be affected by using various values of of Prandtl number in numerical simulations and can be predicted well. However, it affects the exact prediction of axial concentration to extent, and a smaller value of Prandtl number tends to forecast a smaller axial concentration than real one, and vice versa. A reasonable range of turbulent Prandtl number for various Reynold numbers was suggested.

Abstract: As lifting points for ship block turning over and hoisting operation, the strength of the lifting eye directly affects the safety of the operation, therefore it is required for extreme high reliability. The conventional strength analysis can not exactly describe the actual stress and working conditions of the lifting eye, nonlinear contact and simplified finite element arithmetic are used for analyzing and checking the lifting eye's strength in this paper; and the stress force distribution formula, which can well reflect the true status of the pressure-bearing surface, is researched. Through the comparison of the various calculation methods, it can be found that the reasonable simplified method can approach the nonlinear contact finite element arithmetic with high precision and is characterized with higher calculation speed and more concise and practicable.