4 results about "Critical energy" patented technology

This application provides an ultrasonic-assisted forming method for capillary glass tubes used in optical inspection, applied to a forming apparatus including an ultrasonic base and a metal core needle. After preheating the forming apparatus to a first temperature, molten glass is poured in, causing it to coat the core needle and tend to form a transiently solidified layer. An acoustic model is established by collecting the effective working length of the core needle and the material's acoustic parameters. Based on the acoustic model and considering the critical energy density required to destroy the transiently solidified layer and the effective glass forming time, the acoustic energy output parameters of the core needle are determined. According to these parameters, high-frequency ultrasound is continuously applied through the ultrasonic base during the cooling process of the glass from the molten state to a second temperature, causing the core needle to vibrate to destroy and suppress the transiently solidified layer. The ultrasound is then turned off. This method can reduce interfacial stress concentration, suppress the formation of microcracks on the inner wall, and improve the smoothness of the inner wall of the capillary glass tube as well as its optical and mechanical properties.

This invention proposes a method and storage medium for evaluating the reliability and lifespan of thermal barrier coatings, comprising: S1, characterizing and analyzing the microstructure of the sample to obtain the microscopic morphology image of the ceramic layer and the property parameters of the sample, and establishing a geometric model; S2, conducting coupled thermal shock and CMAS corrosion experiments on the sample until its failure, recording load parameters and determining the main failure modes and CMAS melt penetration behavior through cross-sectional analysis; S3, forming a set of thermo-coupling failure control equations based on the main failure modes and penetration behavior; inputting the geometric model and the set of thermo-coupling failure control equations into finite element software for solving to obtain simulated crack morphology and stress distribution results; S4, establishing a limit state equation based on the set of thermo-coupling failure control equations with the actual critical energy release rate as the criterion; S5, calculating the failure probability based on the limit state equations; S6, constructing a lifespan prediction model based on the limit state equations to predict the lifespan of the thermal barrier coating under test.

This invention discloses a transient stability analysis method and system for a multi-machine grid-connected system. First, a transient model of the system is established, and the stable equilibrium point before the fault is determined based on the power balance equation and the eigenvalues ​​of the Jacobian matrix. Using the stable equilibrium point as initial values, the fault trajectory is calculated, and an interpolation correction algorithm is introduced to eliminate discrete simulation step size errors and accurately locate the point on the fault trajectory where the potential energy derivative changes from positive to negative. Using this point as an initial value, the system iteratively searches for the minimum point of power imbalance along the gradient descent path. Solving the power balance equation using the minimum point as an initial value yields the dominant unstable equilibrium point. Finally, the energy of the dominant unstable equilibrium point is used as the critical energy to determine whether the system is stable after the fault is cleared. The method provided by this invention reduces the conservatism of the traditional energy function method for stability assessment in multi-machine systems, effectively reduces the multi-saddle point interference problem in multi-machine systems, and accurately locates the dominant unstable equilibrium point related to the fault path.

There is a need for improved shaping materials for 3D printing having improved printing characteristics, including but not limited to those related to light penetration depth or through-print characteristics. 【Solution】In one aspect, a shaping material intended to be used with a three-dimensional (3D) printing system is described herein. In some embodiments, the shaping material described in the present invention includes an acrylate component, a photoinitiator component, a non-curable absorption component, and water. The photoinitiator component of the shaping material is operable to initiate curing of the acrylate component and / or any other curable material that may optionally be present when the photoinitiator component is exposed to incident curing radiation having a Gaussian distribution of wavelengths and a peak wavelength λ. The shaping material has a penetration depth (D p ) and a critical energy (E c ). In some embodiments, D p is greater than 200 μm and less than 300 μm, and E c is 3 - 12 mj / cm 2 . In other embodiments, D p is greater than 10 μm and less than 50 μm, and E c is 5 - 40 mj / cm 2 .