Advanced Materials Research Vols. 354-355

Abstract: With the purpose of optimizing the combustion system of a homogeneous charged gasoline direct injection engine, its working process was simulated with a 3-D CFD software package. The authors investigated the influence of injection timings and combustion chamber shapes on the charge motion, fuel injection and their influence on fuel-air mixture formation. With the comparisons of fuel-air mixture quality and combustion processes between two typical injection timings, the optimal injection strategy was chosen. To further improve the mixture quality, configuration on piston crown was optimized and analysis on mixture formation processes of the new configurations was made. Simulation results indicate that the new configurations have faster fuel evaporation rate and better mixture homogeneity.

Abstract: To reduce exposure and increase concealment, AIP (Air Independent Propulsion) power plant came into being. In a variety of AIP power devices, closed cycle diesel CCD (Closed Cycle Diesel Engine System) AIP system is the most commonly used at present. Drawing on the principle of existing CCDAIP closed cycle diesel, This paper presents a design about Zero Release Closed Cycle Diesel Engine System, which uses oxygen generation device to produce O2 for the fuel combustion by absorbing CO2，in order to realize the truely zero emissions of conventional submarines without exhaust trail. The paper also takes a preliminary exploration of the design.

Abstract: To reuse the existing power quality systems; share the information and support the changing of management business process in power quality, a power quality management platform based on Service Oriented Architecture (SOA) is proposed. The platform architecture is divided into five layers; the components of each layer are expounded. A business process of disturbance load evaluation implemented by Business Process Management (BPM) is illustrated. By using the architecture in real systems, conclusion can be made that the proposed architecture is feasible.

Abstract: Based on the virtual prototyping technology and flexible multibody system dynamic theory, the author founded the rigid-flexible coupling multibody dynamic analysis model of the crank and connecting rod mechanism of diesel engine, combining the means of 3D solid modeling, finite element analysis and multi-body dynamic simulation. Through the simulation, the dynamic loads in the working cycle of the mechanism are obtained, which provides reference for dynamic stress and fatigue analysis of the mechanism.

Abstract: This paper will put forward a device installed into the fuel system, which can use the sliding electric arc to electrolyze the natural gas to make hydrogen and then blend them in the fuel pipe for final combustion. This device can help to make a new type of HCNG engine fuel system, which electrolyses the single fuel (natural gas) partly to make appropriate-rate hydrogen for combustion. And in this paper, this new fuel system will be described in detail. The picture of sliding electric arc is shown in the end of this paper.

Abstract: A model for on-line calculation of equivalent stresses in steam turbine rotors has been built up based on Support Vector Machine (SVM) neural network and the finite element method. Regarding 125MW steam turbine rotor as an object, SVM method is employed as a tool to train large numbers of date about the equivalent stress of the rotor, which obtained from the finite element method. A model can be gotten after finishing training the data. Equivalent stresses of rotor obtained with finite element and SVM model are compared during cold start. Results show that similar calculation results of equivalent stress may be obtained with either finite element or SVM model. However, with the latter one, the calculation becomes easier and fast, which is applicable for on-line calculation of equivalent stresses in turbine rotors, and may serve as a reference for on-line life management of turbine rotors.

Abstract: In this paper, the finite element model of some car’s body-in-white is established in Hypermesh. The model analysis is executed based on the element model in ANSYS. Through the model analysis the dynamic parameters of the body-in-white are obtained. At the same time，the modal test of a real car body is implemented. The reliability of the finite element model is validated based on the modal test. The results show that the stiffness of the body-in-white is great enough and it can provide optimal design for future designers.

Abstract: Fault diagnosis is an important technical method to improve the safety index and economic effectiveness of wind turbines, it also provide support to advanced maintenance and design in wind power equipment. In this paper, we have done vibration testing on two wind turbines, one is in normal, the other is with faulty, and then carried on comparative analysis of vibration signal to the experimental data, finally designed a fault diagnosis method for direct-driven wind turbine generators.

Abstract: Methanol and diesel are almost not soluble, which greatly limits the further study and popularization of the methanol-diesel fuel. To study the emission and combustion characteristics, the 4100 turbocharged and intercooled diesel engine was fueled with 0# diesel and M10 with different additives in the experiment. The result shows that, the maximum cylinder pressure and the peak of the heat release rate in the initial stage of combustion for M10 with iso-octanol and isooctyl nitrate as additive are higher than that of diesel, while the soot emission is lower and NOx emission is slightly higher than diesel’. The maximum cylinder pressure and the heat-release peak in the initial stage of combustion for M10 with dimethyl ether as additive are both lower than diesel’, and the NOx and soot emissions are obviously decreased. The power of the two blend fuels is lower than that of diesel but the magnitude is small, meanwhile the HC emission is slightly increased, while the CO emission is little declined.

Abstract: The atomization characteristics of a certain type of aero engine fuel nozzle are discussed in this paper. The nozzle atomization characteristics have great influence on the combustion efficiency, ignition, outlet temperature field and pollution emissions. The flow characteristics, atomization particle size and distribution under different working conditions are obtained in this paper through the Phase Doppler particle analyzer and laser Doppler velocity system (PDPA / LDV). The test results show that to the dual pressure atomization nozzle, the flow rate range is wide and droplets size decreases with the increasing oil pressure, and tends to stabilize. The test data provide a reliable basis for the pressure atomizing nozzle design and modified.