Aiming at the problem that the machine loss and fuel loss are large and prone to accidents when the steam turbine is started, the calculation of the thermal stress of the rotor is studied, and the calculation formula of the rotor thermal stress is derived. According to the continuous damage theory, the fatigue damage calculation of the rotor is discussed, and the optimization and starting problem of the steam turbine is discussed from the minimum total loss. The results show that the thermal stress at the start-up of the turbine is not as low as possible, but there is an optimal value, and the starting benefit is best around this value.

In the process of injection molding, the non-uniform filling speed of the melt front will lead to inconsistent orientation and non-uniform shrinkage and warpage deformation, and the ideal filling mode should keep the MFV unchanged as much as possible during the filling process. The key to controlling MFV is to optimize the injection flow rate of the mold filling process. In order to solve this problem, the genetic algorithm and numerical simulation technology are combined for the optimization of the injection molding filling process, and the optimal control point in the screw stroke and the optimal value of the injection volume flow rate at the control point are determined to obtain uniform and consistent MFV.

Using AutoCAD secondary development technology, a three-dimensional modeling system for heat exchange equipment parts was developed under the environment of Visual C++ 6.0 and ObjectARX 2000. Using extrusion, rotation and Boolean operations, given the basic parameters, the <>D solid model of the heat exchange equipment parts is automatically created, the design parameters are modified, and application examples are given. The system is convenient, time-saving, friendly interface, reliable operation, and realizes computerized parametric drawing from data to drawing. Practice has proved that the system saves time and improves the design analysis efficiency for the pre-processing and modeling of FEA parts of heat exchanger equipment.

A portable computer based on self-developed board and a universal data acquisition and signal analysis system based on Paradox database developed by C++ Builder are designed, with keyed phase channel, displacement channel and acceleration channel, which can be used for free acquisition, synchronous full-cycle acquisition and analysis of steady-state and transient signals of rotating machinery and reciprocating machinery. The selection and design of database were discussed, a fast query mode was established, and finally the data collection and management function based on relational database was realized. Experimental results show that it is stable and reliable in industrial sites and easy to upgrade and expand.

The main technical links of XML document application are introduced, two different XML document parsing technologies based on event-driven and tree-based structure are analyzed, the characteristics and applicable environments of event-driven and tree-based parsing technologies are compared, and the method of converting streaming text data into XML data by using XML parsing technology with tree structure is given, which solves the problem of converting the residual data of patent application documents into XML files.

The application progress of vibration technology in the polymer molding process, the basic concept of chaos and the method of chaos control were introduced, and it was pointed out that the aggregate state of polymer is a chaotic state, the transition process of polymer state is chaotic motion, and the polymer melt rupture phenomenon is a manifestation of chaotic motion. The molding process of polymers is a complex chaotic motion. The existence of vibration waves controls and interferes with the chaos of polymer melt flow and the chaos of viscoelasticity, and the study of the motion state of polymer melt under the action of vibration wave needs to be carried out by combining chaos theory with practical experimental results.

The fatigue limit of metal materials is usually obtained by testing and fitting with numerous experimental conclusions, which is expensive and sometimes it is impossible to obtain values under special working conditions. A simple calculation method for estimating the asymmetric cyclic fatigue limit σr is given, which can use limited data to determine the fatigue limit of materials, reduce the number of tests, and reduce the requirements of test conditions. After determining the fatigue limit value and static tensile strength limit, the Ding’s formula was used to draw the isolife curve by AUTOLISP, the determination method of each parameter in the sum formula was discussed, and the sum result and experimental data were compared. The results show that the results obtained by this method are in good agreement with the experimental results, and it is convenient and fast to draw the fatigue curve.

The composition design of multi-component iron-based amorphous Fe-Ni-P-B (TM-M) and Fe-Co-Ni-Zr-Nb-B (TM-(Zr,Nb)-M) systems was analyzed from the aspects of amorphous forming capacity and magnetic properties of the alloy, and the amorphous strips were prepared by the method of rapid quenching of single-roller copper wheel, and X-ray diffraction and transmission electron microscopy (TEM) analysis proved that the samples prepared in this study were uniform amorphous alloys. In addition, it can be seen from the hysteresis loop of the amorphous alloy that the prepared Fe-based amorphous alloy has good magnetic properties.

The effects of component composition on the relationship between peak height, peak width and temperature frequency of the blends α internal consumption of the blends were investigated. The results showed that the relationship between peak height and temperature frequency of the α internal consumption of the blend was between the pure components, and changed regularly with the composition of the components. The relaxation spectrum of the PEO/PMMA system is significantly wider than that of the pure component, while the relaxation spectrum width of the SAN/PMMA system is similar to that of the pure component. It is believed that because the glass transition temperature of the two components of PEO/PMMA is very different, the distribution of glass transition temperature and relaxation time becomes wider due to the fluctuation of composition, so the relaxation spectrum is also wide.

Numerical simulation was applied to calculate the unsteady state temperature field in the process of bimetallic compositation. Due to the different characteristics of temperature changes of the outer material and the core material in the solidification process, different weight coefficients are selected to calculate the temperature. At the same time, in the calculation of temperature, the influence of various factors such as thermal resistance of bimetallic composite bonding interface, latent heat release during solidification process, and thermal conductivity are considered. The temperature values at different locations are collected by thermocoupled, and the collected temperature curves are compared with the simulated temperature curves, and the results show that the simulated temperature curves can reflect the actual temperature changes.

Aiming at the problem that the curve machined by the workpiece under eccentricity is a circle or a heart-shaped line, the influence of workpiece eccentricity on the position accuracy and shape accuracy of the machined surface is analyzed, and it is pointed out that in the turning process, the eccentricity of the workpiece will cause the coaxiality position error between the machined surface (outer circle or hole) and the shape error of the roundness and cylindricality of the machined surface. The machined surface is neither a circle nor a heart-shaped line. Therefore, it provides an important theoretical basis for improving the accuracy of turning machining.

The structural characteristics of impedance matched balance transformers are briefly described, the negative sequence current under different load conditions is calculated and analyzed, the change law of current asymmetry on the high voltage side is described in the form of a curve, and a set of measured currents is given. The analysis results show that the impedance matched balance transformer has a significant effect on reducing the negative sequence current injected into the power grid under electric traction load.

Drawing on the idea of simulated moving bed (SMB), a set of mobile multifunctional chromatographic separation pilot plant was designed for purifying citric acid and other processes. Using the control system based on PROFIBUS bus and soft PLC, the overall division of labor of the system software follows the two-layer mode, the configuration management is realized by the configuration software WinCE, and the control function adopts the soft PLC solution WinAC.

Starting from the basic working principle of memory, according to the sampling theorem, the memory is studied theoretically, the function of function transformation of memory is summarized, the idea of designing function generator by DDS method is proposed, and on this basis, the application example of programmable multiple analog continuous function generators composed of EPROM is given. The results show that the function generator designed by this method has the characteristics of high intelligence and controllable parameters.

The mathematical model used in the optimal control design is always different from the actual system, and the control parameters designed according to this are not completely consistent with the reality. To solve this problem, a method is proposed to analyze the robustness of the stability of linear optimal control systems. Using Matlab’s special control function tool, the influence of parameter changes such as time constant and magnification in some links in the system and the selection of weighted matrix on the robustness of the system was analyzed. The simulation results show that the proposed method can specifically analyze the influence of each part on the stability of the system, which is conducive to system maintenance and system safety.

Aiming at the robustness analysis problem of linear optimal control system, this paper proposes to study the dynamic relationship between system parameters and stability margin by taking the system stability margin as the calculation object, so as to obtain a visual description of the robustness of the system. This method uses Matlab’s control function programming program to continuously solve the algebraic Riccati equation, and obtains the change trend of system stability margin with parameter perturbation, and then displays it by computer graphing. The simulation results show that it has practical value for the analysis of the optimal control system with accurate mathematical model.

Aiming at the problems existing in the existing reinforced concrete plane element models, the combined model of the reinforced concrete plane problem quadrilateral elements under various reinforcement forms is established, and the general expression of the element stiffness matrix of these models is derived. The comparative analysis with the diffusion element model shows that the combined element model not only conforms to the basic theory of finite element discretization, but also can accurately reflect the actual structural effect of steel bars, which has strong practicability.

The data processing methods in wind tunnel simulation atmospheric boundary layer test are introduced from the aspects of average wind speed profile and turbulence structure, and the formulas of friction velocity u*, dynamic roughness height z0 and exponential α in the exponential law are given by curve fitting method, the calculation of turbulence integration scale and boundary layer simulation ratio are discussed, and how to judge the rationality of average wind speed profile simulation by the trend of V~LNZ curve and the dispersion degree of exponential α. The analysis results point out that due to the insufficient turbulence characteristic data, the turbulence characteristic parameters of the simulated flow field will deviate from some literature data, which cannot be said to be unreasonable.

The elastic modulus and dry shrinkage value of the new lightweight wall material were experimentally determined, and three finite element models were established, namely the concrete unit without reinforcement, the concrete unit with reinforcement, and the concrete unit and the steel wire mesh unit working together, and according to these three finite element models, the maximum principal stress and the maximum cracking length of crack under various dry shrinkage values were calculated. The relationship between wall cracking and load, material properties, reinforcement ratio, etc., as well as the reasons for wall cracking and crushing, are analyzed, which provides a basis for the use of this new wall material in actual engineering.

According to the characteristics of the expanded pipe network, the optimization design objective function directly takes the pipe section diameter as the solution variable is constructed, and the generalized minimalistic gradient method (GRG) with obvious optimization effect is used to calculate by taking advantage of the hydraulic characteristics of the constraints, and the problem of solving the pipe diameter standardization is solved at one time through the objective function transformation.

The 20-node space block unit was used to divide the aqueduct body and the trough pier, and the coupling degree of freedom, low stiffness block unit and multiple spring units were used to simulate the lateral tie rod and stiffener of the trough body, the water body in the aqueduct and the basin rubber support, and the finite element model of the dynamic analysis of the structure of the large double-trough aqueduct was established, and the dynamic characteristics of a large double-trough aqueduct of the South-to-North Water Diversion Project were analyzed under multiple working conditions, and the influence of various factors such as the transverse tie rod of the aqueduct, the water body in the trough and the basin-type rubber support on the overall dynamic performance of the aqueduct was discussed. The calculation results show that the influence of the transverse tie rod of the aqueduct on the transverse dynamic characteristics of the aqueduct cannot be ignored, the vertical stiffness of the basin rubber support affects the dynamic characteristics of the aqueduct within a certain range, and the water level and distribution in the aqueduct have a great influence on the dynamic characteristics of the aqueduct.

Starting from the basic hypothesis analysis of TOPMODEL, the physical concept and overall structure of the model are discussed, and the differences between the traditional lumped model and distributed hydrological model are compared, pointing out that the TOPMODEL model is more appropriate than the traditional hydrological model for the simulation of the actual hydrological process, and it is easier to update the data, and it is simpler than the distributed hydrological model, with fewer preferred parameters and easy to use. At present, the development of TOPMODE model theory and application at home and abroad mostly focuses on the change of parameters and the form of basic equations, and some theoretical issues need to be further studied, such as the adjustment of model microstructure and topographic index calculation method in specific application.

Using Bayesian estimation method, using prior information, prediction information and sample information, the prior distribution, the posterior distribution under the prediction information, and the posterior distribution under the fitting information are derived, six combined prediction methods of the value yt0 of the quantity to be predicted at t time are given, and compared. Finally, the influence of subjective parameters on the model results is analyzed.

The solubility and crystalline metastability zone of p-hydroxyphenylglycine sulfate in water-acetone-acidity solution were determined by laser monitoring device. From the analysis results, it can be seen that with the increase of water in the solvent, the solubility of p-hydroxyphenylglycine sulfate increases slightly; The acidity increases, and its solubility increases significantly. The acidity of the solution has a great influence on the width of the metastable zone. Finally, the solubility data are correlated with the simplified solubility model, and the calculated solubility and experimental values are in good agreement.

Nitrite in water has many hazards to humans and animals, ion exchange, reverse osmosis, electrodialysis, biological and denitrification, chemical and chemical catalytic nitrification can remove nitrite from water, these methods have their own advantages and disadvantages. The ion exchange method concentrates nitrite in the medium or waste liquid, which is easy to cause secondary pollution; The biological method has the characteristics of high efficiency and low consumption, but the investment is large; Although chemical reduction can reduce nitrite to harmless nitrogen, its reaction needs to be carried out at higher temperatures and has low efficiency. For the treatment of nitrite in underground deep water with low content and small processing capacity, the chemical oxidation method has the advantages of simple equipment and low treatment cost.

The theory and application of roundness error evaluation are discussed, a mathematical model of roundness error is constructed, and the roundness error is obtained according to the minimum condition by using the substitution algorithm. An example of roundness error evaluation is given, and the results prove that the method has high accuracy and speed. In addition, this evaluation method has strong versatility and can provide a reference for solving other shape errors.

In view of the shortcomings of the closed nature of traditional instruments and the difficulty of function expansion, a set of networked signal analysis and data processing experimental benches based on virtual instruments are designed with LabVIEW as the development platform. The experiment is completed on the simulated rotor test bench, and the corresponding sensors and measuring instruments are configured according to the needs to realize the acquisition of engineering signals, and then the processing, display and printing of the collected data are realized in the developed signal analysis software, and HUB and multiple terminal displays can be configured, and a small LAN can be established, and finally the experimental test network can be realized.