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In order to understand heat transfer of the shell condenser in the closed-loop thermal propulsion system of the unmanned underwater Vehicles, the one-dimensional thermal model based on the hull-integrated condenser with helix channels is developed. After this, experimental research is conducted. Through the experiment data and theoretical calculation results compared, the accuracy of the heat transfer mathematical model is verified, and the correlation formulas about heat transfer are developed. In addition, the impacts of three factors on the performance of the shell condenser are investigated, including cross-sectional area of the cooling channel, flow rate and temperature of inlet steam. The research results indicate that the model and the correlation formulas about heat transfer is reliability and accuracy, which can provide a theoretical basis for simulation and optimization design of the shell condenser.

This paper built a hybrid power system, including wind power, PV power and hydro power generation. It is presented mathematical model for the optional design of hybrid power system. The object of the model are to minimize the initial investment cost, power supply reliability and power complementation. The constraint condition are included system working, installed capacity and load balance, So the capacity matching model is established. A stand-alone photovoltaic of pasturing area is calculated by using the model. The result shows that the optional design model have an important sense, which improved power supply reliability, complementary characteristics of hybrid power and reduce the total cost of the system.

According to the jet hole configuration mode of bionic jet surface and its influence on the drag reduction, as the basic form of jet hole configuration is the isosceles triangle elements, so this was used to establish the computational model of jet hole configuration. In this case, the height and base of the triangles were considered as variable. The SST k-ω turbulence model was used to simulate and research the drag reduction characteristics of bionic jet surface in different configuration modes of jet holes at the main flow field velocity value of 20m/s and the jet velocity value of 0.4~2.0m/s. Also the influence of different configurations of height and base on drag reduction characteristics of bionic jet surface was studied, which got the optimum size of jet hole configuration. Results show that in triangle configuration elements, the drag reduction characteristics of bionic jet surface can be influenced by the jet hole of different configurations of height and base; the drag reduction of bionic jet surface reaches the peak of 32.74% at 8mm height, 11mm base, and the jet velocity value of 2.0m/s. At the same flow field velocity, the drag reduction rate results achieved by experimental tests and by numerical simulation were changing consistently and were found same, which verifies correctness of numerical simulation results.

This paper focuses on the switching power amplifier of magnetic suspension support. The principle of magnetic suspension support was described. Due to the particularity that the load of magnetic suspension support is inductive, the response speed, efficiency and stability should be considered when the switching power amplifier is designed. In the power amplifier, PI circuit can make feedback current follow the given signal in time. In this paper, the amplifier adopts pulse width modulation (PWM) control strategy. The design of PI circuit, PWM circuit as well as the driving circuit were presented in the paper. After completing the designs of all parts, we choose MULTISIM as simulation software, which can establish an accurate circuit model. The simulation results show that the switching power amplifier designed in this paper has bigger bandwidth and less distortion and it can respond timely.

It is of significance for pile foundation design and construction to predict the penetration depth accurately of the displacement pile under a fixed pressure. A new type cone penetrometer and corresponding exploration methods are developed through increasing weight of the device, enhancing the strength of probing rod and probe, and embedding a new function on measuring the total penetration resistance. Not only applied appropriately to various strata except for pebble bed, functions such as the total penetration resistance determination, soil layer classification and soil compression modulus and dynamic-static friction ratio calculation are also provided. Data of total penetration resistance, static point resistance and side friction are measured with the new type cone penetrometer, a new coefficient of dynamic-static friction ratio is introduced and employed to calculate the dynamic side friction, a new estimation method, with which the influence of dynamic side friction is take into account, on penetration depth evaluation of the displacement pile is established and proposed subsequently. Validity of the new method is verified by means of case study of pile engineering and the results indicate, for its high accuracy, the method proposed is of practice and theoretical significance, as well as valuable for popularization.

The non-linear diffusion techniques were proposed for overcome the linear diffusion defaults. The linear diffusion was a homogeneous diffusivity with a constant conductivity. In this diffusion process, the noise and the edges were smoothed in the image. In order to prevent the edge from being smoothed during the denoising, the nonlinear diffusion was proposed by Pereona and Malik. In this method, noise was smoothed Simultaneously with the edges blurred. In diffusion processes, the conductivity is dependent on the image local information. We analyzed the ineffectiveness of isotropic and extended the work into the tensor-based anisotropic diffusion. It would be desirable to rotate the flux towards the orientation of interesting features. We compare the difference of isotroic linear and non-linear anisotropic diffusivity, and considere how to design non-linear anisotropic conductivity based on the different requires of the image filtering.