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The noise emitted from distribution transformer often disturbs the normal life of people around it, hence it is necessary to research the noise characteristics of the vegetable insulating oil transformer. The characteristic of noise emitted by the 10KV vegetable insulating oil transformer under the condition with no load and different loads were tested in a spacious HV testing hall. As a comparison, the vegetable insulating oil in transformer was replaced by mineral insulating oil, and the noise of the transformer filled with mineral oil has also been measured in the same environment. The experiment results demonstrated that A-weighted sound pressure level of noise emitted from the transformer filled with vegetable insulating oil is about 5~6dB lower than that of noise emitted from the transformer filled with mineral insulating oil. Combined with the characteristics of insulating oil and the classical calculation formula of absorption coefficient, the sound absorption coefficient calculating formula of insulating oil has been derived. Though the calculation, it was found that the sound absorption coefficient of FR3 is about 2 times higher than that of mineral insulating oil. Thus vegetable insulating oil FR3 can reduce the transformer noise better than mineral insulating oil.

In order to make full use of the air in the chamber, improve the mixing process, reduce raw emission and fuel consumption of diesel engine, a novel combustion system, the Side Swirl Combustion System (SSCS), was proposed in the present paper. The effects of the distance between the flange and the nozzle (DBFN), a crucial parameter to the designing of SSCS, on the performance of the diesel with SSCS adopted were studied by numerical simulation. The results show that, adopting SSCS can improve the diesel engine's performance. Moreover, with the increase of DBFN, the quality of the fuel-air mixing is worsened.

Fuel-air mixing process is one crucial key to determine the performance of a diesel engine, and it is crucially determined by swirl within cylinder. For generating strong swirl within the cylinder, a new device named swirler has been propounded. In the present paper, four swirlers have been employed to experimentally study the performance on both the discharge capability and swirl generation capability. The steady flow test bench was employed to study the both capabilities in macro-level. Then, a water-flow model was employed to observe the flow motion within the cylinder via the tested swirlers. The results indicate that adopting swirler with a suitable configuration could generate strong swirl without remarkable discharge capability loss.

With the strict implementation of the emissions regulations, the electronic control of diesel fuel injection system is the development trend for diesel engine in the future. Diesel Electronic Unit Pump (EUP) enjoys the advantages of digital control of fuel charge and injection pulse width and also reliability in operation, thus has a strong value in the field of high-power diesel engine. In this paper, the authors have given the overall design for the higher voltage drive circuit which is conducted in accordance with the requirements of diesel engine electrical control unit pump drive, with dive Peak&Hold as its basis. The testing result shows that the minimum operating interval of this higher voltage drive circuit is 5ms, high-voltage peak current of electric-magnetic valve reaches 20A, maintaining current is 15A, action responding time is within 200µs, and low-voltage maintaining current is 8A. The circuit can meet the requirement of electrical control unit pump to higher voltage drive circuit.

Experiment was carried out on a steady flow test bench by using constant pressure drop steady flow measurement method to explore the characteristics of intake port on diesel engine both under naturally aspirated and supercharged conditions. The results showed that: under naturally aspirated condition: with the increase of pressure drop, discharge coefficient and swirl ratio hardly varied at a certain valve lift; under supercharged condition: with the increase of pressure drop, discharge coefficient and swirl ratio decreased at a certain intake pressure; with the increase of intake pressure, discharge coefficient and swirl ratio increased at a certain pressure drop; under supercharge condition, discharge coefficient was higher than that under naturally aspirated condition and new method should be promoted to evaluate the intake port on supercharged diesel engine.

The 5th female dummy (SID-IIs) added in the new FMVSS214 regulation is different from the ES-2 in structure and performance of biologic mechanics. Based on DOE method, the response surface methodology is adopted to model the thorax rib characteristic of SID-IIs. This paper focuses on analysis of the different factors related to the rib displacement.

By comparing dummy injury in frontal crash tests, this paper discuss the difference of the frontal and rear dummies, and the reason causing the differences is analyzed. It is of enormous significance to promoting and improving the passive safety of vehicle.

To enhance the running efficiency of AVS decoder in the embedded platform, an optimized method was proposed based on the L1P cache, the program code is divided to 4 modules, the capacity of each module is smaller than the capacity of L1P, change the traditional processing pattern by order aiming to single macro block, make every program module process the data of one macro block row in turn, thus reduce 4×M×(N-1) code washout. The experiment result show the method based on L1P cache enhances the efficiency of processor reading program code, makes the decoder speed enhance 20%.

Ample intake charge and suitable intake flow motion can improve the combustion quality in diesel engine for it can promote the mixing process between air and fuel. But enough air charge is more difficult to reach for high blower engine. The stead flow test method under naturally aspirated condition is usually used to obtain the flow characteristics of engine intake port. But it may over-evaluate the flow ability when the intake port is used for a high blower engine. The characteristics of intake flow under supercharging condition have rarely been studied in past. Therefore, it is necessary to make study on the relation between the supercharging pressure and intake flow characteristics for supercharging diesel engine. In this paper, the authors have completed experiments under supercharging condition. The test data showed that the flow coefficient and swirl ratio is reduced with pressure difference increase between inlet and outlet of the port, and the flow coefficient and swirl ratio increases with intake pressure increase.

Swirl is an important flow pattern of air motion, it not only affects the fuel-air mixing and combustion processes in diesel engine, but also has a significant impact on heat transfer, combustion quality, and engine-raw emissions. For generating swirl efficiently, many researches have been performed, however, almost the methods have more or less crucial disadvantages. For overcoming these shortcomings and generating more efficient swirl during the intake process, the authors design a new device, swirler, to induce intake swirl in non-swirl intake port diesel engine. In this paper, the authors design four types of swirler including one straight-shaped swirler and three arc-shaped swirlers. In order to research the fundamental characteristics of swirler, the authors make series of experiments researches. The total researches can be divided into three stages: in the first stage, steady flow tests are carried for researching the swirl capability and the discharge capability of swirler from the macro-level, in the second stage, flow fields in the cylinder are measured by Particle Image Velocimetry (PIV) technique in the water analog tests for researching the swirl performance from the micro-level, at last stage, the tested swirler is installed on a certain type of actual diesel engine for studying whether swirler can improve the engine operation performance noticeably. The results show that this new device can induces intake swirl efficiently and can improve fuel economy at on an optimized swirl ratio.

Double swirl combustion system, which is abbreviated to DSCS, is a new combustion system. For its noticeable effect on improving the fuel-air mixing process and reducing raw emissions, it has been accepted and applied widely. Double swirl combustion chamber, as one of the most important components of the DSCS, plays an important role to affect the fuel-air mixing processes and the fuel-air mixture quality which controls the combustion processes. Hence, make the further researches on the DS combustion chamber and design an optimized DS combustion chamber is very necessary and important. However, there has no reports about the researches on the configuration parameters of DS chamber have been published. Therefore, the authors make the research on parametric design of DS combustion chamber, to find out the main configuration parameters of DS chamber, and then explore how those configuration parameters affect the performance of DS chamber. In this paper, the authors make analysis on the configuration structure detailedly, and determine the crucial configuration parameters of DS chamber, and then, the authors make series of simulation researches on those parameters to reveal their effect rules, and indicate the design direction of DS chamber based on those results.

A concept of forced swirl combustion chamber in diesel engine is proposed in this paper. It can be used to enhance the intensity of swirl flow in the cylinder and accelerate the rate of air-fuel mixture process by designing the special structure in the combustion chamber. This new type of forced swirl combustion chamber includes double swirl combustion chamber that was discussed past and partial swirl combustion chamber that is mentioned in this paper. Firstly, the calculative result of double swirl combustion chamber by CFD code FIRE is calibrated by the method of Validation & Verification with experiment data. By the effect of the special structure of the ridge and slope in partial swirl combustion chamber, the rate of air-fuel mixture and combustion process has been accelerated twice by comparing with the calculative result of these two combustion chambers. At the same time, the utilization of air in squish zone has been improved. The characteristic of double-peak has appeared within main combustion duration on the instantaneous heat release rate curve of partial swirl combustion chamber. The result of calculation shows that NOx and soot mass fraction of partial swirl combustion chamber is lower than that of double swirl combustion chamber by 8.2 and 7.4 percent respectively, and indicated heat efficiency is 2.2 percent higher.

Aiming to some problems of armored vehicles research and development, such as few new types, few costing data and long research and development(R&D) cycle, it discussed some key techniques about R&D costing analysis of the armored vehicles, including identifying conversion coefficients about time worth, calculating dynamic and static expense and yearly expense distribution. Then, using parameters modeling method based on non-linear multi-regression technology, it built a prediction model between R&D costing and performance parameters of the armored vehicles. The model can be used to predict R&D costing of one new vehicle whose performance parameters are confirmed. The research results are significant to armored equipments life cycle costing(LCC) analysis that is comparatively weak currently in China.