Advanced Materials Research Vols. 430-432

Abstract: Based on the literature research of the characteristics of domestic and foreign shale gas reservoir-forming conditions, in this paper we mainly study the development characteristics of organic-rich shale in Lower Paleozoic of Chongqing northeast, organic geochemical characteristics, reservoir characteristics, combined with geological survey and sample testing, analyse and study the development of shale, reservoir-forming conditions and distribution of shale gas to establish favorable target area and the resource potential prediction.

Abstract: Contamination of groundwater by petroleum-hydrocarbons is a widespread environmental problem. Generally in plumes of petroleum-hydrocarbon contamination, the dissolved oxygen (DO) demand imposed by biodegradation of organic contaminants exceeds the DO available creating anaerobic conditions within the plume core and mid-plume areas. The objectives of this bench-scale study were to (1) develop oxygen-releasing materials for continuous oxygen supplement, (2) determine the optimal components of the studied oxygen release material, and (3) evaluate the oxygen release rate and lifetime of this material. Moreover, the potential of using a passive oxygen release material to clean up aquifers contaminated by petroleum hydrocarbons was also studied. Bench experiments were conducted to design and identify the components of the oxygen-releasing materials. The mixtures of the oxygen release material were prepared by blending gypsum, calcium peroxide (CaO2), sand, and water together at a ratio of 1：0.5：0.14：0.75 by weight. Cement was used as a binder and regular medium filter sand was used to increase the permeability of the mixture. Calcium peroxide releases oxygen upon contact water (2CaO2 + 2H2O → O2 + 2Ca(OH) 2). The designed material with a density of 1.1 g/cm3 was made of 3.5-cm cube for the batch experiment. Results show that the oxygen release rate of the material is 0.025 mg/day/g. The oxygen release material is able to remain active in oxygen release for more than three months. With the application of this developed oxygen release material, the contaminated subsurface can remain an aerobic environment for subsequent aerobic bioremediation. For the future field application, the developed materials can be placed in remediation wells, trenches, horizontal wells, or barriers. Thus, the passive biobarrier system has advantages over conventional system including less maintenance, cost-effectiveness, no above-ground facilities, no groundwater pumping and reinjection, no air pollution problems, and groundwater remediation in situ. The proposed treatment system would be expected to provide a more cost-effective alternative to remediate petroleum-hydrocarbon contaminated aquifers. This technology can also be applied for other hazardous waste contaminated sites.

Abstract: According to the theory of heat transfer, it analyzed the calculating method of tooth friction heating in the process of face gear tooth meshing. It emulational analyzes the thermal coupling of the face gear with ANSYS/LS-DYNA, and extracts the state of each engaged positions in the meshing process, emulate the temperature distribution & temperature changing trends in the process of face gear tooth meshing. Through the temperature measurement experiment the face gear contact, it verifies the correctness of the emulation results. Simultaneously, it also analyzes the influence to the surface temperature of face gear of rotation and load, In the case of other conditions remain unchanged, low-speed is an effective way to prevent instantaneous temperature rise.

Abstract: A maize drying method of salt modulation is presented in this paper. Based on the thin-layer drying experiment [1], the effects of drying air temperature and salt amount on moisture removal rate is analyzed [2], and mathematical model equation is established on relationship between maize moisture ratio and drying time [3]. The experiment result shows that: a reasonable choice of the amount of salt, air temperature and other process parameters is useful to improve drying rate of maize. Salt modulated drying curve is exponentially. The more salt is added in, the faster the moisture removal rate. However, in the case of excessive salt, there may be a critical point of moisture change in the amount of salt until this point the faster the higher the salt amount, whereas the slower; if the critical changing point is higher than the safety moisture point, generally it will conductive to the maize moisture removal process.

Abstract: In view of the multiple performance parameters accelerated degradation and need to consider its dependence, we should know how to statistical analysis on the data of testing, establish multiple performance parameters degradation path model and its distribution model and the accelerated model of degradation rate. The multiple performance parameters degradation data’s statistics has two different situations which are independent and dependent. So, A method is proposed which is multiple performance parameters of reliability comprehensive evaluation method based on least squares parameters estimation. This method can achieve rapid and effective assessment of their reliability by using an efficient Monte-Carlo simulation method to get the performance parameters degradation data.

Abstract: In order to calculate the EMU fatigue calculation of wheels, calculation of fatigue loading to obtain the wheel to solve problems, the method that makes use of multi-body dynamics simulation combined with finite element method is proposed, in time domain the wheel of CHR3 EMU in random loading is conducted the simulation study of the fatigue life. First of all, modal analysis of the wheels and wheel contact analysis are conducted in the ANSYS, and axle contact strength is also analyzed. Second, create a model of the EMU in ADAMS, and simulate to receive dynamic loading process. Finally, combined with the finite element stress method, dynamic loading time history and the linear cumulative damage rule, using ANSYS/WORKBENCH to get the fatigue life prediction chart of the wheel. It can be seen from the results, the safety factor of the most dangerous point of CRH3 EMU wheel type is 1.376, to meet fatigue life requirements, which provide a theoretical basis for the safety maintenance of the EMU.

Abstract: The output performance of Automobile Exhaust Thermoelectric Generator (AETEG) is related to the temperature difference and electric connection topology of thermoelectric modules, in order to decrease the ring current among the thermoelectric modules in parallel with different temperature difference and enhance the output performance, a novel heat exchanger using in AETEG is designed in this paper. The interior structure of heat exchanger with fishbone is analysed, then its surface temperature distribution is simulated with ANSYS software and experimented with thermal imaging instrument. Both of the results show that the surface temperature distribution of the fishbone heat exchanger designed in this paper is more uniform in lateral direction and dispalys an obvious gradient in fore-and-aft surface, compared with the one of cavity designed before, the novel heat exchanger has overwhelming advantage in the output performance of AETEG, and the method adopted in this paper is feasible and practical.

Abstract: Effective implementation of technology of aquifer thermal energy storage (ATES) must form a "ground cold water reservoir" or "ground warm reservoir". In this paper, taking Sanhejian Coal Mine as an example, we analyze the effect of cold energy storage in single-well by analyzing the volume change of cold water body within different temperature ranges. Through the analysis of volume change of cold water body, it can prove that with the same irrigation temperature, the increase of irrigation flow makes the volume and percentage of cold water body in aquifer within different temperature ranges. And the impact on the cold water of 2-5°C is more obvious. With the same irrigation flow, both the cold water body and its percentage of 2-10°C in the condition of 2°C irrigation temperature are more than those in the condition of 5°C. The increase of irrigation flow and the decrease of irrigation temperature are beneficial to cold energy storage, and the effect of cold energy storage of the condition 3 (100m³/h irrigation flow and 2°C irrigation temperature) is the best in these four conditions.

Abstract: The rotor mass imbalance is main reason of rotating mechanical vibration. A new dynamic balance weighting method for single-disk rotor system based on phase difference mapping is presented. Firstly, the influence coefficient method and its characteristics are analyzed in detail. Secondly, the equivalent phase difference mapping relationship between incentive and vibration response for single-disk rotor system is proved by differential equations and Laplace transform theory. Finally, a specific application instance is showed. The new method is simple and easy to peel the phase coupling relationship between incentive and response, which can be used to guide dynamic balance weighting for single-disk rotor system on site.

Abstract: Research on spindle system of a machine tool, using Solidworks software to establish the spindle assembly model, using ANSYS finite element analysis method to analyze the dynamic rigidities of spindle systematacially. Compare dynamic rigidities of test with the motorized spindle were analyzed. Validate dynamic rigidities of the spindle accord with dynamic characteristic.