56 results about "Thermal diffusivity" patented technology

The invention relates to an overmolding method for producing a component (1) having a decoration (2), also referred to as an overmolded part, said decoration (2) being made of an at least partially amorphous metal alloy (8), said method comprising the following steps: providing a blank (3) having at least one through-hole (4) which opens into the overmolded part (2) to be produced, said blank (3) being made of a first material having a low thermal diffusion coefficient or being at least partially plated with a layer made of said first material; providing an injection mould (6); positioning the blank (3) inside the injection mould (6); the liquid metal alloy (8) is injected through the through hole (4), and the through hole is communicated into the cavity of the injection mold (6) and / or the cavity of the blank (3); the blank (3) with the overmolded part (2) is demolded in order to obtain the component (1).

The invention relates to the technical field of tree management, and discloses an ancient and famous tree dynamic early warning and intervention decision-making system based on a health diagnosis model, and the system comprises the steps: collecting physical and chemical parameters of a target tree according to a preset position at a fixed time interval; constructing a health diagnosis model: performing cycle fitting processing on the temperature parameters of the daily time sequence to obtain fitting data; respectively determining a phase lag time, a thermal diffusivity and an amplitude ratio based on the fitting data; determining the heat variation of the soil, determining the corrected surface heat flux by combining the heat flux parameters, and extracting the peak value of the daily corrected surface heat flux; performing combined judgment processing on the volumetric water content, the dry density, the phase lag time, the thermal diffusivity and the amplitude ratio to judge whether the target tree is in a false water shortage state or not; in response to the false water shortage state of the target tree, determining the risk level of the target tree according to the peak value of the corrected surface heat flux; and generating an intervention decision scheme based on the risk level of the target tree.

The invention discloses a cutting control method for a steel structure product, which comprises the following steps: collecting data of a steel structure, establishing a three-dimensional stress field according to the collected data of the steel structure, and generating a three-dimensional stress distribution diagram by the three-dimensional stress field; collecting the heat conductivity coefficient and the heat diffusivity of the steel, and establishing a heat conduction model according to the heat conductivity coefficient and the heat diffusivity; identifying a stress sensitive area according to the three-dimensional stress distribution diagram, and planning a cutting path according to the three-dimensional stress distribution diagram and the stress sensitive area; an active heat management system is designed, the active heat management system comprises a temperature sensor, a cooling liquid spraying device and a control system, and heat input and heat dissipation strategies can be more accurately designed by researching stress heat conduction characteristics, so that the phenomena of local overheating and heat stress concentration are reduced.

The present application relates to the technical field of dynamic positioning of steel material local heating cutting, and discloses a steel material cutting positioning system, which comprises a cutting energy source numerical control controller and a thermal signal sensing base station which moves integrally with a workpiece, wherein the actual thermal diffusivity of the workpiece is self-calibrated through double-point inquiry before cutting, and in the cutting, the thermal pulse emitted by the energy source is responded by the base station and the real position is solved through three-side measurement to generate a coordinate offset value to correct the subsequent path in real time, the present application directly establishes the measurement reference on the workpiece body, so that the physical drift and deformation of the workpiece caused by local heating are converted from a continuous cumulative positioning error source into a background condition which is real-time surveyed and internally eliminated in each position solving, thereby solving the problem of dynamic disconnection of the coordinate system.

The present invention is a battery pack having a battery cell, a cooling plate, and a battery case that accommodates the battery cell and the cooling plate, the battery pack being provided with an adhesive sheet that adheres the battery cell and the cooling plate, the adhesive sheet having a reduction rate of thermal diffusivity before and after heating represented by formula (1) of 4.5% or more when the adhesive sheet is heated at 285 DEG C for 5 minutes. ((thermal diffusivity before heating-thermal diffusivity after heating) / thermal diffusivity before heating) * 100... (1) According to the present invention, it is possible to provide a battery pack provided with an adhesive sheet which has both excellent thermal conductivity in general and excellent thermal insulation properties during thermal runaway.

This invention discloses a method and system for quality acceptance of concealed sprinkler installation based on infrared thermal imaging, relating to the fields of building fire protection facility acceptance and non-destructive testing technology. The method includes: modeling and calibration, establishing a material parameter library containing thermal diffusivity, thermal conductivity, and temperature resistance limits, and completing coordinate system alignment and time synchronization; controlled excitation and triggering, applying hot / cold pulses to the pipe network or connecting metal parts where the sprinkler is located and recording the frequency band identifier; acquisition and preprocessing, obtaining infrared image sequences before, during, and after excitation and extracting temporal observation features such as isothermal contour radius, temperature difference response, temperature gradient center, and contour ellipticity; determining update weights based on signal-to-noise ratio, occlusion, and excitation effectiveness, and performing block fusion and recursion with time decay; installation geometry and fastening status estimation, outputting the sprinkler's position, tilt angle, extension amount or elevation, and fastening status indicators within the ceiling plane; compliance judgment and reporting, generating conclusions and rectification suggestions based on threshold-weighted scoring.

A method of deriving a thermal conductivity value and a thermal diffusivity value for a sample including the steps of providing a sample container comprising a solid annular cylinder of a material with a known thermal conductivity and a known thermal diffusivity, the internal radius of the annular cylinder defining a cylindrical sample space; providing the sample in the cylindrical sample space; applying heat to the sample along the central axis of the cylindrical sample space; taking temperature readings over time in the sample or in the annular cylinder at a first point of known radial distance from the central axis; and using the temperature readings to derive the thermal conductivity value and the thermal diffusivity value.

This shape-changeable structure comprises a non-deformable part and a deformable part. The non-deformable part has a first stiffness and a first thermal diffusivity. The deformable part is formed continuously with the non-deformable part and has a second stiffness lower than the first stiffness and a second thermal diffusivity lower than the first thermal diffusivity.

The invention belongs to the technical field of testing of physical properties of rock and soil, and particularly relates to a device and a method for testing thermal physical properties of expansive rock and soil, which ensure that a rock and soil sample is in a required humid and hot condition by accurately adjusting the temperature and humidity of an experimental environment. The expansion change of the rock and soil sample is synchronously recorded by acquiring displacement data. And all monitoring data are transmitted to a computer in real time for processing and storage. And the computer analyzes the thermophysical properties (such as heat conductivity coefficient, specific heat capacity, thermal diffusivity and the like) of the rock-soil sample in real time according to the collected data, and finally outputs an accurate test result. The whole working process ensures accurate measurement and efficient test of the thermal physical properties of the expansive rock and soil in a complex humid and hot environment.

The invention provides a non-contact thermal diffusivity measurement method and device of an anisotropic thin film material, and relates to the technical field of thermal diffusivity measurement of thin film materials. The method comprises the following steps: performing beam expansion and shaping on continuously emitted stable laser, and performing dynamic beam shaping and focusing to obtain a laser beam form with variable spatial distribution; meanwhile, the center of the annular heating spot is accurately aligned with the geometric center of the film sample, and the size of the annular heat source is adjusted. A non-contact temperature sensing array is adopted, infrared radiation is synchronously sampled, space-time temperature distribution data of the surface of a film sample is obtained, a thermal simulation algorithm and a machine learning model are input, fitting and dynamic comparison optimization parameters are carried out, and a final anisotropic thermal diffusivity value is obtained through inversion. The method has the advantages of non-contact, quick response, accurate characterization and inversion of in-plane anisotropic thermal diffusivity parameters of the material and the like, and solves the problems of poor sample applicability, local high temperature points, high cost and the like.

The invention provides a heat distribution optimization method and a portable moxibustion therapy instrument, and belongs to the technical field of medical instruments.The thermal diffusivity and thermal conductivity of a skin contact area are measured through a transient plane heat source method, and thermophysical parameters of multi-layer tissue are inversely recognized in combination with a genetic algorithm; a Kalman filter is used for fusing temperature and pressure sensing data to estimate contact thermal resistance and convective heat transfer coefficients in real time to update boundary conditions of a biological heat transfer equation set, and a segmented control strategy is started according to temperature deviation to select maximum power pulse heating or fuzzy proportional integral differential control. The compressed sensing theory is utilized to reconstruct full-field temperature distribution from sparse temperature data and calculate a high-gradient area heat dose accumulated value to output a safety early warning signal, and the technical problem that a portable moxibustion instrument is difficult to achieve deep tissue effective heating and surface layer safety temperature control balance under different individual thermophysical property differences and dynamic boundary conditions is solved.

A vacuum insulating panel may include: a first glass substrate; a second glass substrate; a plurality of spacers provided in a gap between at least the first and second substrates, wherein the gap is at a pressure less than atmospheric pressure; and a seal having at least one layer provided between at least the first and second substrates. Additive(s) may be provided in material(s) for the seal in in order to improve thermal diffusivity and / or thermal conductivity thereof.

The application discloses a kind of measurement system and method based on phase distribution inversion thin film material cross-scale thermal diffusivity, through unified time base and unified reference phase condition, the cooperative acquisition of macroscopic full-field lock-in observation and microscale scanning observation is realized, and the joint inversion framework of phase distribution matching and scale consistency is established, form the measurement process that can be checked, can be closed loop, to realize the thermal diffusivity of thin film material from micron to millimeter scale range in the same experimental system, efficient, stable characterization, improve cross-scale data consistency and inversion reliability, reduce the error and cost caused by repeated measurement, and enhance the adaptability to interface effect and non-uniform structure influence.For and improve the existing method, it is difficult to consider full-field positioning and microscale effect identification in the same measurement framework, the cross-scale data is not comparable due to the non-uniformity of phase reference, and the inversion stability is insufficient.

To overcome the technical challenge of only being able to measure the thermal diffusivity at a single location, we provide a device for measuring the thermal diffusivity of a material. [Solution] The measuring device includes a base, a modulated laser module fixed to the base, a beam shaping and focusing module, and a drive module. Above the beam shaping and focusing module is a vacuum sample chamber module, and above the vacuum sample chamber module is an infrared camera module that can move freely up and down. The drive module drives the infrared camera module to move freely up and down. The modulated laser module emits a laser beam to the beam shaping and focusing module, the beam shaping and focusing module guides the laser beam to the vacuum sample chamber module to irradiate the material, and the infrared camera module acquires a thermal image sequence of the material after heating.

This invention discloses a high-temperature solid particle interseasonal thermal storage system, comprising a vertical silo body, a closed gas circulation loop, and a heating device. The vertical silo body is filled with a solid particle thermal storage medium, which is surface-modified and coated with a nano-alumina coating. It also includes a multi-component composite insulation structure covering the silo wall, consisting of, from the inside out, a high-alumina refractory brick layer, a ceramic fiber blanket buffer layer, a nano-aerogel felt layer, and a microporous calcium silicate board layer. A sloped temperature layer control module is used to calculate the position and thickness of the sloped temperature layer in real time based on an effective thermal diffusivity model, maintaining the sloped temperature layer thickness within a set range. A multi-scale simulation prediction control unit is used to predict the sloped temperature layer trajectory in advance and calibrate and update the effective thermal diffusivity model. This invention enables large-scale, long-term (half-year) interseasonal thermal storage at the GWh level, while ensuring stable heat release temperature and minimal heat loss.

The invention discloses a samarium-doped oxygen calcium lanthanum borate nonlinear optical crystal material for pulse amplification and a preparation method and application thereof.The crystal material belongs to a monoclinic system, an m point group and a Cm space group, the chemical formula is Smx: La1-xCa4O (BO3) 3, x is 0.1-0.99, the thermal diffusivity is 0.865 mm / s and 0.531 mm / s at the temperature of 300 K and 600 K respectively, the specific heat capacity is 0.691 J.g <-1 >. K <-1 > and 0.871 J.g <-1 >. K <-1 > at the temperature of 300 K and 600 K respectively, and the samarium-doped oxygen calcium lanthanum borate nonlinear optical crystal material is a samarium-doped oxygen calcium lanthanum borate nonlinear optical crystal material. And the transmittance of the samarium-doped oxygen calcium lanthanum borate crystal material in the range of 500-900 nm and the transmittance of the samarium-doped oxygen calcium lanthanum borate crystal material in the range of 1600-2400 nm reach 85% or above, so that the samarium-doped oxygen calcium lanthanum borate crystal material can be used as a nonlinear optical crystal material with a wide application prospect in a quasi-parametric chirped pulse amplification system.

The present application relates to the rapid determination of the thermal conductivity-based green building insulation material detection and screening system, and relates to the thermal physical property measurement and temperature sensor technical field.The system comprises a transient plane heat source probe integrated with a high-density micron-level embedded micro temperature sensor array, a temperature sensing unit and a data processing unit, through synchronous acquisition of near-field multi-point temperature response and operation of multi-physical field coupling inversion and signal collaborative filtering algorithm, at least two of the thermal conductivity, the thermal diffusivity and the volumetric heat capacity are decoupled and output.The present application can solve the problem of poor repeatability caused by weak signal and environmental interference in the measurement of high thermal conductivity or high heat storage materials, and realize the overall accurate evaluation of the thermal physical properties of the materials in a single test.

The invention discloses a concealed nozzle installation quality acceptance method and system based on infrared thermal imaging, and relates to the technical field of building fire-fighting facility acceptance and nondestructive testing, and the method comprises the steps: modeling and calibration: building a material parameter library containing thermal diffusivity, heat conductivity coefficient and temperature resistance limitation, and completing coordinate system alignment and time synchronization; performing controlled excitation and triggering, applying hot / cold pulses to a pipe network or a connecting metal piece where the nozzle is located, and recording a frequency band identifier; acquiring and preprocessing to obtain infrared image sequences before, during and after excitation, and extracting time sequence observation characteristics such as isothermal contour radius, temperature difference response, temperature gradient center and contour ellipticity; determining an update weight according to the signal-to-noise ratio and the shielding and excitation effectiveness, and performing block fusion and recursion along with time attenuation; estimating mounting geometry and fastening state, and outputting the position, inclination angle, extension or elevation and fastening state indexes of the nozzle in the ceiling plane; and performing compliance judgment and reporting, and generating a conclusion and a rectification suggestion according to a threshold weighted score.

The application provides a frequency modulation type annular laser heating thin film thermal diffusivity transient measurement method and device, and relates to the technical field of thin film material thermal diffusivity measurement. The method comprises the following steps: generating a cosine electrical signal and converting the same into radio frequency power through a driving circuit to obtain a periodic heat flow with cosine distribution over time on the surface of a sample through laser modulation; the modulated light beam is expanded, phase shaped and bright spot eliminated to form an annular heating light beam and realize non-contact rapid heating and generation of a uniform annular heating zone; a micro displacement table is used to adjust a thermocouple probe to a light contact state on the back of the heating zone to collect an original temperature measurement signal; then, the signal is phase-locked amplified and post-processed to finally obtain the thermal diffusivity of the thin film. The application can significantly improve the non-destructiveness and high signal-to-noise ratio of the temperature measurement process, solve the problems of uneven heat flow distribution and large edge heat loss, and realize rapid and accurate evaluation and measurement of the thermal transport characteristics of the thin film.

Tissue-mounted devices and methods for monitoring a thermal transport property (e.g., thermal conductivity, thermal diffusivity, heat capacity) of tissue, such as skin, are disclosed. The devices conformally mount to the tissue and comprise one or more thermal actuators and a plurality of sensors. The actuator applies heat to the tissue and the sensors detect a spatio temporal distribution of a physiological tissue parameter or physical property resulting from the heating. This spatio temporal information may be correlated with a rate, velocity and / or direction of blood flow, the presence of a vascular occlusion, circulation changes due to inflammation, hydration level and other physiological parameters.

The embodiment of the invention discloses a heat insulation material screening method and device, electronic equipment and a readable storage medium. According to the method, boundary conditions are determined according to the thickness of a heat insulation material and the constant temperature applied to the front face of the heat insulation material at the initial moment, and initial conditions are determined according to the initial temperature of the heat insulation material; then solving a heat conduction equation according to the initial condition and the boundary condition to obtain a solution of the heat conduction equation, and realizing theoretical solution of a change relation of temperature with respect to space and time; and finally, determining the upper limit of the thermal diffusivity according to the constraint temperature of the back surface of the thermal insulation material and the theoretical solution, so that the proper thermal insulation material can be quickly selected according to the upper limit of the thermal diffusivity, thereby improving the design efficiency of the high-performance thermal insulation layer and reducing the manufacturing cost of the high-performance thermal insulation layer.

A polyarylene sulfide (PAS) foam layer that circumscribes a hollow inner tube and may have a 50% or greater density reduction relative to the density of an un-foamed PAS polymer material and / or a 50% or greater thermal conductivity reduction relative to the thermal conductivity of an un-foamed PAS polymer material and / or 50% or greater thermal effusivity reduction relative to the thermal effusivity of an un-foamed PAS polymer material. The PAS foam layer may have a low density (e.g., less than 0.67 g / cc) and / or a low thermal conductivity (e.g., anywhere from 0.017 W / (m-K) to 0.145 W / (m-K)) and / or a low thermal effusivity (e.g., less than 316 Ws1 / 2 / m2 / K, optionally anywhere from 38 Ws1 / 2 / m2 / K to 316 Ws1 / 2 / m2 / K) even at high temperatures (e.g., above 400 degrees Fahrenheit (° F.) (about 204 degrees Celsius (° C.)). Such a PAS foam layer may have characteristics appropriate for use as part of a steam hose.

The embodiment of the invention provides a carbon material and a preparation method thereof, a display screen and electronic equipment, the carbon material comprises a plurality of stacked carbon atom layers, the in-plane thermal diffusion coefficient of the carbon material is larger than or equal to 800 mm < 2 > / s, the Young modulus of the carbon material is 1000-6000 Mpa, the surface roughness Ra of the carbon material is smaller than or equal to 800 nm, and the elongation at break of the carbon material is larger than or equal to 2%. The carbon material has ultrahigh thermal diffusion coefficient, high modulus, low surface roughness and relatively high elongation at break, and can be used in appearance devices such as a flexible display module, so that the devices have good bendability and appearance delicacy while having high thermal conductivity.

The present application relates to the technical field of composite insulation layer, specifically to a container battery cabin composite insulation layer design method and system, in the present application, by establishing the initial parameter matrix composed of layer sequence coding, thickness vector, interface thermal resistance, honeycomb sandwich and corrugated geometric parameters and cabin wall heat exchange and radiation coefficient, the heat insulation performance evaluation can obtain accurate baseline under multi-dimensional input condition, through gradient boosting regression tree under the constraint of thermal conductivity, thermal diffusivity and propagation time, difference comparison and iteration screening is carried out, so that the heat insulation combination can gradually approach the optimal solution in the convergence process, avoid the deviation caused by the experience in the parameter selection in the traditional structure design, adopt simulated annealing algorithm to execute difference operation and convergence judgment on honeycomb size, wall thickness, height and corrugated geometric parameters, combined with finite element checking to ensure that the optimization process considers the requirements of thermodynamics and mechanics, so that the geometric parameters and thermal performance are synchronized to converge to stable combination.

A thermal diffusivity measuring device includes a sample holder, a light source, e.g., pulsed laser or flash lamp, designed to emit a pulse of light of a predetermined impulse energy, an optical system for directing the pulse of light in a light path onto the sample in the sample holder, an infrared sensor for time-dependent detection of an infrared radiation intensity emitted by the sample, and an evaluation unit designed to automatically calculate the thermal diffusivity of the sample on the basis of the time-dependent infrared radiation intensity. In addition, the light source may have a continuous wave laser that is designed to emit an intensity-modulated laser beam, the intensity of which is modulated with an intensity modulation frequency. The light source is arranged to emit the laser beam along a light path. The evaluation unit is designed to automatically calculate the thermal diffusivity of the sample on the basis of the time-dependent infrared radiation intensity and the intensity-modulation frequency.

The present disclosure provides an outer packaging material for a vacuum heat-insulating material, the outer packaging material having a water vapor permeability of 0.1 g / (m2·day) or less and an oxygen permeability of 0.1 cc / (m2·day·atm) or less. The outer packaging material for a vacuum heat-insulating material has a plane-direction thermal diffusivity α and a thickness T which satisfy the following (expression 1). Expression 1: α≤6.375×10-5 / (T×V) (In the expression, α is the plane-direction thermal diffusivity (m2 / s) of the outer packaging material for a vacuum heat-insulating material, T is the thickness (m) of the outer packaging material for a vacuum heat-insulating material, and V is the volumetric specific heat of the outer packaging material for a vacuum heat-insulating material and is 2.2×106 J / (m3·K) to 2.4×106 J / (m3·K).)

An overmoulding method for making an overmould (2) forming a decoration to be added to a part (1) or a part itself, including: providing an ébauche (3) used as an injection tool, the ébauche (3) having at least one through hole (4) forming a channel (5) for injecting the metal alloy (8), the ébauche (3) being made of a first material with a thermal effusivity less than or equal to 7,000 W K−1 m−2 s½ or being at least partially plated with a layer made of the first material; positioning the ébauche (3) inside an injection mould (6); injecting the metal alloy (8) through the through hole (4) opening into a cavity to obtain the overmould (2); and detaching the overmould (2) from the ébauche (3) to form the decoration to be added or the part itself.

The application relates to the technical field of infrared thermal wave nondestructive testing and material thermal physical property measurement, in particular to a high-precision thermal diffusivity inversion method based on a multi-terminal deep neural network. The application aims to solve the problems of low calculation efficiency, strong noise sensitivity and insufficient robustness in the traditional thermal diffusivity measurement method, and proposes a high-precision thermal diffusivity inversion method based on a multi-terminal deep neural network for materials containing damage defects. Specifically, the application uses a phase-locked thermal imaging technology to extract the amplitude and phase of the thermal wave, and obtains stable characteristics describing the thermal diffusion process. A deep learning network is constructed with spatial coordinates, excitation frequency, surface temperature information, amplitude and phase as inputs. Through multi-modal data fusion, advanced direct current component removal technology and multi-terminal deep neural network architecture, efficient and accurate measurement of the thermal diffusivity of complex materials is realized.

The invention relates to a microvascular blood flow monitoring method and an alarm type non-invasive wireless skin flap monitoring sensor, the surface of a skin flap is periodically heated, the temperature rise of skin on the surface of the skin flap is measured, and the heat conductivity coefficient and thermal diffusivity physical property parameters of the skin flap are calculated through measured temperature rise data on the basis of a plane heat source principle. The perfusion index of the flap is further solved based on a Pennes equation in combination with the physical property parameters; when the skin flap temperature and the perfusion index, measured by the monitoring sensor, of the patient are lower than the set crisis temperature and crisis perfusion index, an alarm prompt is triggered. Compared with the prior art, non-invasive wireless high-precision real-time monitoring of postoperative skin flap capillary blood flow, skin flap temperature and skin flap edema conditions is achieved, and an alarm function for vascular crisis is achieved.