77 results about "Specific heat" patented technology

The invention relates to an anti-overtemperature control method and system for an aluminum alloy sheet heating furnace, and the method comprises the following steps: arranging a plurality of thermocouples in the length direction and the width direction in the heating furnace, forming a temperature matrix, and collecting the temperature distribution data of a working area in the furnace in real time; a transient heat conduction prediction model of the aluminum alloy sheet is established, and the model is combined with physical property parameters of aluminum alloy and comprises the relation that the specific heat capacity, the heat conductivity coefficient, the density and the emissivity change along with the temperature; based on the temperature matrix and the transient heat conduction prediction model, predicting a temperature rise curve of the thin plate in a future set time; and when the predicted temperature exceeds the preset safety threshold value, the heating power or the start-stop state of the corresponding heating area is adjusted in advance, and active anti-overtemperature control is achieved.

The invention discloses a gas specific heat ratio measuring device and a gas specific heat ratio measuring method, particularly relates to the technical field of gas specific heat ratio measurement, and solves the technical problems of low measuring precision, inconvenience in operation, poor safety and narrow application range of a traditional gas specific heat ratio measuring experimental device in the prior art. According to the technical scheme, an air pressure sensor measures changes of air pressure and temperature in a bottle, and data can be displayed in real time by being connected with a computer; by optimizing sensor design and a signal processing algorithm, the measuring device can respond to air temperature and pressure changes more quickly; the stepping motor is used for controlling opening and closing of the piston, and errors caused by human factors are reduced; the change of the air specific heat ratio at different temperatures can be explored by changing the temperature; according to the invention, intelligent and automatic measurement is realized, errors caused by manual operation are reduced, and data change visualization in the whole experiment process is provided, so that students can intuitively analyze the change of each physical quantity.

The invention discloses an ORC working medium optimization method and framework based on Jacob number and critical temperature, and relates to the technical field of energy engineering, and the method comprises the following steps: A1, inputting heat source parameters, cold source parameters and a candidate working medium database; a2, calculating thermophysical parameters such as critical temperature, critical pressure and specific heat of each working medium and Jacob number under a design working condition; and A3, defining a dynamic working condition spectrum, analyzing the matching characteristics of the working medium critical temperature and the heat source at different heat source temperatures, simulating the evolution law of the system power and efficiency when the evaporation temperature changes, and tracking the Jacob number and time system performance in real time when the evaporation temperature of different working media changes by constructing the dynamic working condition spectrum. Therefore, a universal working medium optimization criterion is constructed from the perspective of thermodynamics, the problems that the ORC working medium optimization criterion is not uniform and the correlation mechanism of the working medium physical property and thermal performance is not clear are solved, and efficient optimization of the ORC working medium is achieved.

The invention discloses a mechanical friction spark temperature testing method based on multiple thermocouples and particle size analysis, which comprises the following steps of: 1, preparing a test piece, processing the surface of a friction test piece, and fixing an embedded thermocouple array in the test piece; secondly, dynamic pressure loading is conducted, and friction pressure is adjusted through a high-pressure air bottle and a piston type air cylinder; 3, synchronously monitoring multiple thermocouples, and arranging the thermocouples to synchronously acquire data; step 4, spark particle size capturing: a high-speed camera and a laser particle size analyzer are adopted to acquire particle size distribution and speed track of spark particles in real time; 5, temperature-particle size correlation correction is carried out, and a temperature attenuation model is established based on the specific heat capacity and the heat conductivity coefficient of spark particles; and step 6, data fusion output: fusing and outputting analysis results. A plurality of thermocouple arrays are arranged at the center and the edge of a friction interface and on a spark splashing path, and temperature data in the friction heat and spark cooling process are synchronously collected.

A water-cooled heat dissipation and monitoring system includes a pump, water-cooled piping, a water-cooling block, a water-cooling radiator, multiple temperature sensors, and a microcontroller. The pump and water-cooled piping are used to transfer the coolant. The water-cooling block is in thermal contact with a power element. The water-cooling radiator is used to facilitate heat exchange between the coolant and the surrounding environment. Multiple temperature sensors are located at at least two different points along the water-cooling path. The microcontroller is connected to the multiple temperature sensors and the pump, and is used to obtain at least one temperature difference at at least two different points and a measured flow rate of the coolant. Based on the at least one temperature difference, the measured flow rate, the specific heat capacity and density of the coolant, the microcontroller obtains an estimated power consumption and an estimated temperature of the power element, and controls the pump's rotation speed to adjust the coolant flow rate based on the estimated temperature.

In the method according to the application, the substance to be tested (FL) is allowed to flow through the pipeline in the specified flow direction, and the wall temperature value X Tw is ascertained, which represents the wall temperature T w of the wall of the lumen of the pipe, which encloses the pipeline. Furthermore, the density value X p of the density p of the substance to be tested flowing in the pipeline, the viscosity value X μ of the viscosity μ of the substance to be tested flowing in the pipeline, the thermal conductivity value X λ of the temperature conductivity λ of the substance to be tested, the heat capacity value X p of the specific heat capacity c cp of the substance to be tested, and the pressure difference value X Δρ of the pressure difference Δρ generated in the substance to be tested flowing in the pipeline in the flow direction are ascertained and then used to ascertain the characteristic number value X V of the characteristic number V of the substance to be tested, which characterizes the heating of the substance to be tested flowing in the pipeline as a result of dissipation, wherein the characteristic number V of the substance to be tested corresponds to the calculation formula: V = f(Δp, p, μ, λ, c p ) = Pr a · ec b · ζ c , which is determined by the Eckert number Ec of the substance to be tested flowing in the pipeline, the Prandtl number Pr of the substance to be tested flowing in the pipeline and the pressure loss coefficient ζ of the pipeline, and by the pipeline-specific first exponent a, the pipeline-specific second exponent b and the pipeline-specific third exponent c. Finally, the temperature value X V representing the temperature T Tw of the substance to be tested is ascertained using the characteristic number value X M and the wall temperature value X TM . For this purpose, the measuring system according to the application additionally comprises a temperature sensor, which is thermally coupled to the lateral surface of the wall for generating a temperature measurement signal, which corresponds to a change in the temperature T w of the wall as a function of a change in at least one signal parameter, and a measuring and operating electronics system, which is electrically connected to the temperature sensor.

The present application belongs to the technical field of natural gas hydrate exploitation, and discloses a device and method for real-time nondestructive calculation of equivalent specific heat in hydrate decomposition process. The device comprises a visual flat reaction kettle, a nondestructive high-precision phase state identification system, a gas and liquid inlet and exhaust system, and a computer acquisition system. The principle of the present application is that: through the method of providing uniform heat source by heat conduction outside the reaction kettle, hydrate decomposition is promoted, and internal heat convection can be ignored. Real-time volume fraction of each component is obtained by the nondestructive high-precision phase state identification system, Newton interpolation calculation is used for the volume fraction, latent heat of phase transition of hydrate deposit at adjacent temperature is calculated, and equivalent specific heat of hydrate deposit is obtained. The present application realizes real-time nondestructive calculation of equivalent specific heat field in hydrate decomposition process. The method is environmentally friendly and economical, and the device is clear and visual, which provides technical support for the research on latent heat of phase transition and equivalent specific heat in the process of hydrate exploitation.

The invention discloses a Fe-B-P-C-Cu-Co series amorphous-nanocrystalline transition state structure alloy with an excellent magnetic-electric synergistic effect and a preparation method of the Fe-B-P-C-Cu-Co series amorphous-nanocrystalline transition state structure alloy, and belongs to the field of metal material processing and manufacturing, the chemical components of the alloy comprise, by atomic percent, Fe B Pc < d > Cu < e > Co < f >, a is equal to 80-85, b is equal to 10-15, c is equal to 1-5, d is equal to 0.5-2, e is equal to 0.2-1, f is equal to 0-5, and the balance is inevitable impurities; the mother alloy is prepared by melting raw materials through vacuum induction, and an amorphous alloy thin strip is prepared by adopting a single-roller rapid quenching method; after the amorphous alloy is treated by a specific heat treatment process, the saturation magnetization of the amorphous alloy is 1.81 T, the coercive force is 3.8 A / m, and the resistivity is 117.2 [mu] omega.cm. The method has important theoretical and practical significance for developing amorphous-nanocrystalline transition-state structure alloy with an excellent magnetic-electric synergistic effect.

The invention relates to the technical field of building thermal engineering, solves the problems of inaccurate and incomplete evaluation of the heat storage performance of a building envelope and poor environmental adaptability in the prior art, and provides a method, a device and equipment for evaluating the heat storage efficiency of the building envelope and a storage medium to prepare a target test piece containing a functional material; carrying out a cross-characteristic change temperature interval experiment by utilizing the dynamic thermal and humid climate wind tunnel to obtain nonlinear thermal response data; constructing an enthalpy method discrete numerical model, and performing parameter inversion by taking the minimum root-mean-square error of theoretical surface heat flow and actually measured heat flow as a target to obtain thermophysical parameters and an effective specific heat capacity curve; and constructing a thermal network model based on the inversion parameters, and simulating hourly heat flow of each node of the test piece, so as to calculate a multi-dimensional heat storage efficiency evaluation index of the enclosure structure. According to the method, the high-precision wind tunnel experiment, the nonlinear heat transfer model and the inversion algorithm are coupled, the dynamic heat storage performance of the enclosure structure is accurately quantified, and an accurate and practical solution is provided for evaluating the heat storage efficiency of the functional enclosure structure.

This invention relates to a method and system for simultaneously measuring thermal conductivity, specific heat capacity, and interfacial thermal resistance, belonging to the field of thermophysical property measurement technology. First, a TDTR (Transient Thermal Resonance) measurement is performed on the sample under test using a preset laser spot size and modulation frequency that meet preset criteria, obtaining a measurement signal. Then, the initial parameter values ​​of the sample are input into a heat transfer model to obtain a simulated signal. The initial parameter values ​​are continuously adjusted until the deviation between the simulated signal and the measured signal is less than a preset value. At this point, the initial parameter values ​​are used as the measured parameter values ​​of the sample. Both the measured signal and the simulated signal include a negative delay time period of -20 to -5 ps and a positive delay time period of 0.1 to 4 ns. A single TDTR measurement can simultaneously determine the thermal conductivity, specific heat capacity, and interfacial thermal resistance of the sample, greatly expanding the measurement capabilities of TDTR technology.

This invention provides a method, device, electronic device, and storage medium for continuous casting and rolling temperature monitoring. The method includes determining the current values ​​of multiple first monitoring parameters and multiple second monitoring parameters based on the current temperature distribution and multiple preset mapping relationships. Each first monitoring parameter includes a two-phase composition ratio, and each second monitoring parameter includes a weighted specific heat capacity determined based on the two-phase composition ratio. The two-phase composition ratio is determined based on the current temperature distribution, the length of the temperature range for the austenite-ferrite phase transformation, and the average temperature of the temperature range. Based on the current temperature distribution, the current value of the weighted enthalpy, the current values ​​of each second monitoring parameter, and a preset finite difference heat conduction equation, the estimated enthalpy for the next moment is determined. The current value of the two-phase composition ratio is used as the estimated ratio value for the next moment, and the estimated temperature value for the next moment is determined based on the estimated enthalpy for the next moment. This invention introduces the thermodynamic effects of the austenite-ferrite phase transformation to improve the accuracy of temperature monitoring.

The present application relates to the technical field of cold storage. Specifically disclosed are a cold storage material, and a preparation method therefor and the use thereof. The cold storage material comprises a Gd2O2Se crystal. The cold storage material in the present application comprises the Gd2O2Se crystal, and the Gd2O2Se crystal has a phase transformation near 6.22 K, a relatively large specific heat in a temperature range of 1-10 K, and an obvious magnetothermal effect and can be used as a cold storage material at a liquid helium temperature.

A method for determining the adiabatic temperature rise of high fly ash concrete, which can accurately reflect the temperature change of high fly ash concrete, take into account the early age and later period, and more flexibly and accurately simulate the actual hydration heat process of high fly ash concrete. It comprises: (1) obtaining the thermal conductivity, temperature conductivity, bulk density, specific heat, linear expansion coefficient and Poisson's ratio of high fly ash concrete through experiments, and obtaining the initial adiabatic temperature rise parameters of high fly ash concrete through adiabatic temperature rise test; (2) determining the first part of the model first, using the measured data of the dam body and combining with simulation calculation to obtain the first part of the model; (3) using the thermometer pre-buried in the structure to measure the temperature rise value of the concrete after reaching the minimum temperature in the actual project, and according to the relationship between the data and the age, the second half of the model is analyzed by regression analysis to obtain the adiabatic temperature rise parameters of the second half of the model formula; (4) obtaining the complete formula, and calculating the concrete temperature field according to the formula.

The application relates to a high-power millimeter wave power online measurement method and device, and belongs to the technical field of power density measurement. The method comprises the following steps: a to-be-measured millimeter wave beam is incident to a test screen; the temperature of each pixel point on the test screen is obtained by using an infrared thermal imager; the infrared thermal imager deviates from a transmission channel of the to-be-measured millimeter wave beam; the power of the to-be-measured millimeter wave beam is determined according to the specific heat capacity, density, temperature rise and dielectric constant of the test screen and the angular frequency and pulse width of the to-be-measured millimeter wave beam; and the application can solve the technical problem that in the prior art, a directional coupler is used for online power measurement and monitoring of high-power millimeter waves, and the accuracy of the measurement result cannot be guaranteed.

The invention discloses a method for predicting thermodynamic parameters of drilling fluid based on basic physical properties of the drilling fluid. The method comprises the following steps: obtaining a relational expression between the thermodynamic parameters and basic physical property parameters of the drilling fluid; according to the basic physical property parameters of the to-be-tested drilling fluid and the relational expression, the thermodynamic parameters of the to-be-tested drilling fluid are predicted; wherein the thermodynamic parameters at least comprise one of specific heat capacity and heat transfer coefficient; the basic physical property parameters comprise density, solid phase content, oil-water ratio and viscosity. According to the scheme, the specific heat capacity and the heat conductivity coefficient of the drilling fluid under different basic physical properties can be accurately and rapidly calculated, the prediction accuracy rate reaches 90% or above, a large number of repeated and complicated thermodynamic parameter testing experiments conducted through a specific instrument are avoided, and basic data are provided for establishing a shaft temperature distribution model and regulating and controlling the temperature of the drilling fluid.

The application discloses a simulation method of track control thermal jet interference effect containing temperature influence, and comprises the following steps: determining the parameters of the flow Mach number, momentum and total enthalpy according to the real flight flow conditions, and determining the parameters of the real gas jet total pressure, total enthalpy, specific heat ratio and nozzle outlet momentum according to the real track control engine gas jet parameters; determining the ground research scaled model geometric size under the condition of ensuring the geometric similarity of the research configuration and the nozzle according to the ground research flow conditions, using air or gas jet to simulate the real track control engine gas, and simulating the jet and the flow momentum ratio and the total enthalpy ratio; and obtaining the force interference factor of the track control thermal jet interference and the track control deviation by using the ground wind tunnel test or numerical simulation method. The application can be used for thermal jet interference wind tunnel test or numerical simulation.

This invention provides a method for the overall identification of the isobaric specific heat capacity of a variable-property working fluid, comprising the following steps: conducting heat transfer tests on the variable-property working fluid under different inlet temperature conditions to obtain the inlet and outlet temperatures and the total heat transfer of the variable-property working fluid under various operating conditions; obtaining the maximum and minimum temperature values ​​of the inlet and outlet temperatures under all operating conditions, dividing the temperature range into intervals with fixed temperature intervals, and using the lower limit temperature of each temperature range as the qualitative temperature of the isobaric specific heat capacity of that temperature range; establishing an artificial neural network for each temperature range, using the inlet and outlet temperatures and the total heat transfer of the heat transfer process under different operating conditions as sample data, and training all artificial neural networks simultaneously to achieve the identification of the isobaric specific heat capacity of each temperature range. This invention effectively improves the identification accuracy by using the overall identification approach of "multiple operating conditions instead of multiple measurement points" to identify the isobaric specific heat capacity of a variable-property working fluid.

This invention discloses a four-step inversion method for thermal properties based on analytical models and unsteady-state numerical models, comprising the following steps: 1) Using water temperature observation data after the 10th hour of the thermal response test, the thermal conductivity of the soil and rock is calculated using the linear slope method based on a linear heat source analytical model; 2) Using water temperature observation data after the 10th hour of the thermal response test and the obtained thermal conductivity of the soil and rock, assuming the thermal conductivity and volumetric specific heat of the backfill material in the borehole, the volumetric specific heat of the soil and rock is inverted based on a one-dimensional unsteady-state numerical model in the entire space; 3) Using water temperature observation data from the first two hours of the thermal response test, the obtained thermal conductivity and volumetric specific heat of the soil and rock, the thermal conductivity and volumetric specific heat of the backfill material in the borehole are simultaneously inverted based on a one-dimensional unsteady-state numerical model in the entire space; 4) Using water temperature observation data after the 10th hour of the thermal response test, the thermal conductivity of the soil and rock, the thermal conductivity and volumetric specific heat of the backfill material are obtained, and the volumetric specific heat of the soil and rock is inverted based on a one-dimensional unsteady-state numerical model in the entire space.

The present application relates to the field of building thermal technology, solves the problem that the existing technology is not accurate, not complete, and poor in environmental adaptability for evaluating the heat storage performance of the envelope structure, and provides an envelope structure heat storage efficiency evaluation method, device, equipment and storage medium, a target test piece containing a functional material is prepared; a cross-characteristic change temperature interval experiment is carried out by using a dynamic thermal and humid climate wind tunnel, nonlinear thermal response data is obtained; a discrete numerical model of enthalpy method is constructed, parameter inversion is carried out with the minimum root mean square error of the theoretical surface heat flow and the measured heat flow as the target, and the thermal physical property parameters and the effective specific heat capacity curve are obtained; a thermal network model is constructed based on the inversion parameters, the hourly heat flow of each node of the test piece is simulated, and the multi-dimensional heat storage efficiency evaluation index of the envelope structure is calculated. The present application couples high-precision wind tunnel experiment, nonlinear heat transfer model and inversion algorithm, accurately quantifies the dynamic heat storage performance of the envelope structure, and provides a precise and practical solution for the heat storage efficiency evaluation of functional envelope structure.

The invention discloses a thermal comprehensive experiment instrument based on a vacuum environment, and relates to optimization of a heat conductivity coefficient and specific heat capacity measurement experiment in a college physical experiment. The thermal comprehensive experiment instrument comprises a vacuum heat insulation device (figure 1), a circulating water cooling device and a thermal comprehensive experiment instrument host (figure 2), wherein the circuit diagram of the thermal comprehensive experiment instrument host is shown in figure 3. In an experiment, heating of a pure resistance heating film (11) is controlled by regulating and controlling output of a direct-current stabilized power supply (26), refrigeration of a semiconductor refrigeration sheet (15) is regulated and controlled by a temperature controller (27), heat generated on the lower surface of the refrigeration sheet is taken away by a water-cooling radiator, finally, a vacuum environment is created by a vacuum pump (1), a sample (13) is clamped between an upper heat-conducting copper sheet (12) and a lower heat-conducting copper sheet (14), and the sample (13) is subjected to heat preservation. A thermocouple thermodetector is inserted into the temperature measuring holes of the upper heat-conducting copper sheet and the lower heat-conducting copper sheet, so that an experiment can be realized. The experimental instrument is a novel basic experimental instrument which can perform normal and efficient experiments in an environment where a traditional experimental instrument generates large experimental errors, and can be widely applied to college physics experiment teaching.

The present application belongs to the technical field of geological survey, and particularly relates to a porosity determination device and method. The porosity determination device comprises: a skeleton volume testing unit for measuring the skeleton volume of a sample by a gas method, the skeleton volume testing unit comprising a first measuring chamber for accommodating the sample; and a total volume testing unit for measuring the total volume of the sample according to the principle of specific heat capacity ratio measurement by a vibration method, the total volume testing unit comprising a connected specific heat capacity ratio measurement assembly and a second measuring chamber, wherein the volume of the internal space of the second measuring chamber is the same as the volume of the internal space of the first measuring chamber, and the first measuring chamber is connected with the specific heat capacity ratio measurement assembly. In the present application, gas is used as the measurement medium, and the skeleton volume and the total volume of the sample can be integrally determined, thereby providing technical support for reducing the influence of human factors, improving error control ability and data comparability in the porosity determination process.

This invention relates to the field of engineering thermophysical testing technology and discloses a method for measuring thermophysical parameters in the construction of a multi-phase model for the thawing of frozen coal in trains. The method first obtains the convective heat transfer coefficient of the train body surface as a function of the convective heat transfer coefficient and temperature through wind tunnel experiments and inversion using Newton's law of cooling. Second, it prepares standard frozen coal samples maintaining a multi-phase structure of ice, coal, and air using vacuum freezing sample preparation technology, and then uses a combination of laser flash calorimetry and differential scanning calorimetry to accurately measure the equivalent thermal conductivity, equivalent specific heat capacity, and latent heat of phase change of the frozen coal at low temperatures. Finally, it outputs a complete package of thermophysical parameters. This invention solves the problem of inaccurate thermophysical property measurements caused by the multi-phase characteristics of frozen coal, providing an accurate and reliable data foundation for constructing a high-fidelity thawing simulation model, and significantly improving the accuracy and reliability of simulation design.

The invention discloses a vehicle cooling liquid amount determination method and a related device. The method comprises the steps that the system net inflow heat of a cooling system, the system heat dissipation capacity coefficient of the cooling system, the system specific heat capacity of the cooling system, the power unit temperature, the power unit temperature change rate and the cooling water amount change rate are obtained; an actual physical equation is constructed, a state observer state-space equation is constructed based on the state observer and the actual physical equation, the output of the state observer state-space equation is the cooling liquid amount, and the cooling liquid amount is calculated by determining the coefficient value of the state observer state-space equation. The cooling liquid amount of the vehicle can be calculated by using the state space equation of the state observer, the coefficient value, the actual input and the actual output, that is, the internal variable cooling liquid amount which cannot be directly detected in the actual physical equation is estimated by using the state space equation of the state observer based on the principle of the state observer, and the cooling liquid amount of the vehicle can be calculated. Therefore, the amount of the cooling liquid can be detected.

A device for studying the relation between tissue temperature and electrical impedance comprises a tissue placing container, a heating and heat preservation subsystem and a tissue temperature and electrical impedance testing subsystem, and has the characteristics that (1) various general instruments are not stacked any more, the subsystems are controlled in a centralized mode, accurate synchronization is facilitated, and (2) the degree of automation is high, temperature adjustment is convenient, and time and labor are saved. The whole temperature adjusting scheme and the whole testing scheme can be set at a computer end at one time, and manual control is not needed in the middle process; (3) the highest heating power is high and can reach 2kW or even higher, and rapid heating is supported; heat transfer modes are various, water bath heating comprises heat radiation and heat conduction modes, and the heat transfer efficiency is high; and (5) due to large specific heat of water, heat preservation and constant temperature of tissues are facilitated, measurement of low-frequency impedance is facilitated, and impedance spectrum measurement of frequencies below 100Hz is successfully covered.

This invention relates to a method and system for calculating and compensating the State of Charge (SOC) of a hydrogen storage system. The invention includes: real-time acquisition of the pressure and temperature of hydrogen gas within the storage container; correction of the pressure based on the pressure and temperature to obtain a standard pressure at 20°C; calculation of the initial SOC value using the pressure-temperature method based on the 20°C standard pressure; acquisition of the heat transfer coefficient, heat exchange area, real-time hydrogen storage mass, and hydrogen specific heat capacity at constant pressure within the storage container, and calculation of a thermal effect compensation coefficient based on the pressure change rate and temperature change rate; thermal effect compensation of the initial SOC value based on the thermal effect compensation coefficient to obtain a thermally compensated SOC value; correction of the hydrogen density based on the second virial coefficient of hydrogen, the real-time absolute pressure within the storage cylinder, and the real-time thermodynamic temperature to obtain a density correction coefficient; and correction of the thermally compensated SOC value based on the density correction coefficient to obtain the final SOC value. This invention improves the accuracy and stability of SOC calculation for hydrogen storage systems.

The invention discloses a gas specific heat ratio determination experiment device and method based on an isolated gas system, and the device comprises a height bottom plate, the top of the height bottom plate is fixedly connected with a first connecting rod, the top of the first connecting rod is fixedly connected with an inflation and exhaust all-in-one machine, and the side wall of the inflation and exhaust all-in-one machine is communicated with a first connecting pipe. One end of the first connecting pipe communicates with a high-pressure air chamber, and a temperature and pressure sensing device is arranged in the high-pressure air chamber. The invention relates to the technical field of teaching aids for demonstrating physical phenomena. Through cooperation of the air inflation and exhaust all-in-one machine, the first connecting pipe, the high-pressure air chamber, the second connecting pipe and the non-elastic thick-skin balloon, the device is suitable for measurement of various kinds of gas, an isolated gas system is directly used as a research object, the experiment precision is effectively improved, students can conveniently and directly compare the measurement process with the adiabatic expansion process rule of the gas, and the experiment efficiency is improved. And the dependency relationship of each physical quantity of the learned gas in the measurement can be more intuitively understood.

The application discloses a kind of mixed molten salt solid heat storage materials, preparation method and application, belong to heat transfer heat storage material technical field, mixed molten salt solid heat storage material is eutectic salt, including component one and component two, the mass percentage of component one is 90.0~99.5%, the mass percentage of component two is 0.5~10.0%, wherein, component one includes NaCl-Na2SO4, component two includes magnesium chloride.The application uses sodium chloride, sodium sulfate and magnesium chloride as raw materials, adds MgCl2 in binary eutectic system NaCl-Na2SO4 of same cation, greatly improves the specific heat and thermal conductivity of molten salt material under the condition that the influence on melting point and decomposition temperature is small, the use temperature range is wide, and it is conducive to promoting the development of molten salt energy storage technology.

[Problem] Thermal conductance of a heat source is grasped to contribute to the effective utilization of unused thermal energy. [Solution] A thermal conductance measuring method includes: connecting the other end of a thermal conduction path to a heat source to be measured, the thermal conduction path having a cooling source at one end (S10); installing a heating element in the thermal conduction path, the heating element controllable to fluctuate a heat generation amount by applying fluctuating heating energy to the heating element; measuring a temperature within the thermal conduction path and acquiring a first temperature affected by heat generation by the heating element and a second temperature not affected by heat generation by the heating element (S30, S50); and calculating thermal conductance of the heat source based on a difference between the first temperature and the second temperature (S60) and the heating energy when the first temperature was measured (S80). Since this allows the thermal conductance of the heat source to be calculated without the need to grasp a specific heat, mass, or the like of the heat source, it is possible to contribute to the effective utilization of the unused thermal energy possessed by the heat source.