Papers by Keyword: Model Analysis

Abstract: This study aims to review variation pattern of moisture content ratio of grains in deep-bed drying process, guide the drying technology design, realize real-time tracking and regulation in drying process, improve the quality of drying process and reduce energy consumption. Based on the moisture diffusion model in thin layer drying process, the principle of mass conservation of deep drying process, state function and irreversible thermodynamics analytic method, we have established and solved basic equations of deep-bed drying of grains, obtained the moisture content ratio of grains and analysis formula of drying velocity distribution in processes of concurrent flow drying, counter flow drying, cross-flow drying and standing drying and resolved the sustained decreasing drying process of grains in the concurrent flow drying and extreme point of drying rate in the counter-flow drying. Under the same conditions of temperature, humidity and air output, the drying velocity in counter-flow drying significantly higher than that in the concurrent flow drying. It means the energy utilization effects in counter-flow drying is better than that in the concurrent flow drying. Drying characteristics of grains in cross-flow drying and standing flow drying are the same, while drying rates in inlet-air side and outlet-air side vary widely. It means that when the layer thickness is 0.5m and the moisture content is over 20%, the drying rate in outlet-air side is nearly zero and the drying uniformity is bad. Tests on 5HP-3.5 recirculation drier shows that maximum deviation between analytic value and measured value in deep drying process is 0.69% and the range scope is -0.27%-0.69%. From the drying characteristics of grains, deviations mainly come from instrument detection deviations. The analytic method has important significance for realizing real-time tracking and regulation in drying process, guiding drying technology design, reducing energy consumption, increasing drying rate and drying machine capacity.

Abstract: A certain type of special computer was studied as the institute in this paper. Through researching on the structure of the special computer box, use the Pro/E software to create the simplified model of the case, including computer cabinet, PCB, power and fan etc. Model analysis is conducted in the FEA environment ANSYS, attains ten order natural frequency and vibration mode. Dynamic load in the model is applied with half sine impact acceleration, and the resistance performance of the PCB which is the important components of the model is researched by the acceleration, speed and displacement response results obtained. Verify the installation method of vibration isolator can effectively improve the shock resistance of special computer.

Abstract: Combining the method of finite element analysis with fatigue life prediction, fatigue cracks on the shaft parts is analyzed with cyclic loading. Analyzing the shafts with different sizes of cracks in different locations, a simulation modal is established. Informed by analytical and numerical simulation method, the crack formation and propagation life could be calculated. With considering the relationship of "Frequency - crack - fatigue life - remanufacturing ", the remanufacturability of the shaft parts might be evaluated based on service condition. And in this paper, a more convenient way to detecting and predicting the fatigue cracks on shaft parts is given.

Abstract: There are four kinds of ultra-precision lapping machine bed were developed: with/without reinforcing rib, with/without a pair of closed sides. The finite element analysis was used to find the optimal design of the machine bed. The 3D model of the ultra-precision lapping machine bed was built by SolidWorks, and ANSYS software was used for static analysis and modal analysis. The results suggest that when reinforcing rib and a pair of closed sides were owned, the machine bed had some better static and dynamic characteristics. The mix-deformation of this machine bed was 1.911μm, and the first-order inherent frequency was 101.74Hz.

Abstract: The choice of the element type of finite element is different and the division of elaborate degree of meshing is different, so the results of analysis on different modals are different. Combined with the use of ANSYS, specific practice analysis of modals, experimental result, various methods of modal analysis, this article states about the specific methods of modals analysis on carburetor.

Abstract: An automobile will sustain various incentives from the outside and inside in the process of being driven, in which the impact of the wheel and the vibration of engine mainly dominates. This paper gets the inherent frequency through modal analysis on finite element model in a heavy vehicle’s driving cab. And then it conducts the forced response analysis on finite element model by modeling a condition where the vibration of driving cab is caused by outside incentive. Through analyzing, it finds the main response region generated in driving cab when affected by outside incentive. At the same time, it can provide certain theoretical basis for controlling the noise of driving cab in the future.

Abstract: In wireless sensor networks based on ZigBee,we often see such a model that full symmetric transmission model of competition for channel resources based on CSMA/CA algorithm. For the purpose of reducing the energy consumption of entire network,this paper establishes a model that communicate as planned which based on CSMA/CA algorithm.

Abstract: The oblique impact of a golf ball with a rigid steel target was studied using a high-speed video camera. The video images during the impact were employed to measure the compressional displacement of the ball normal to the target and to determine the normal velocity and acceleration of the ball as a function of time. The rotation angle of the ball was also measured to evaluate the angular velocity during the impact. The results showed that the angular velocity increased and then decreased during the impact. To study the velocity change, we introduced an analytical model and suggested that the ball deformation can play an important role to understand the friction effect during the impact.

Abstract: This paper analysis a steel chimney outer wall with a spiral guide plate. Through calculation the steel chimney structure modal, self-vibration and wind vibration frequency verify this steel chimney can reduce the wind load impact on the chimney and flange connection. Achieve a method of improved the strength of chimney structure. The chimney under wind load resonant frequency band is reduced effectively and obtained a more stable exterior structure, offered basis for steel chimney transform in wind vibration problem.

Abstract: In order to analysis the internal relation between the matric suction change and the tunnel disease, the paper combines the Dayoushan tunnel as an engineering example, uses the mathematical, field monitoring and model shear test and to analysis the the change rule of the martic suction and the influence of martic suction on the tunnle supporting force and plastic zone. The results show that when the water content is increasing, the unsaturated loess matric suction is reduction, the force of tunnel support is increasing and the radius of plastic zone is increasing. Due to the influence of surface water infiltration, the matric suction of the around soil in Dayoushan tunnel is reduction and cause the crown settlement, landslides and lining cracks. The disease treatment mainly lies in keeping the drainage system is smooth and secure for waterproof. For the similar unsaturated loess tunnel, the research results have reference significance.