32 results about "Steady state heat transfer" patented technology

The invention discloses a method for calculating the critical air leakage volume that causes the vacuum deterioration of the condenser, comprising: setting initial iteration parameters; performing iterative calculation for each cooling pipe, and drawing the vacuum of the condenser and the air leakage volume The relational curve, in which the air leakage volume corresponding to the inflection point of the curve is the critical air leakage volume that causes the vacuum deterioration of the condenser. Beneficial effects of the present invention: under the condition that the load and the volume output of the air extractor are constant, by establishing a one-dimensional steady-state heat transfer model of the condenser, the change of the vacuum of the condenser when the air leakage volume changes is calculated, so as to determine the The critical air leakage of condenser vacuum deterioration provides guidance for the safe and economical operation of condensers in power plants.

The invention discloses a method for simultaneously measuring internal temperatures and wall thicknesses of high-temperature structures under steady-state conditions. The method has the advantages that the problem of incapability of simultaneously measuring internal temperatures and wall thicknesses of existing high-temperature structures under existing steady-state conditions can be solved by theaid of the method; the method is based on ultrasonic detection signals, and structure thickness and internal temperature simultaneous measurement is transformed into heat boundary conditions of heatconduction problems and multi-parameter identification problems for structure thicknesses; the initial time and time steps are prolonged, transiently solved internal non-uniform temperature field andsteady-state results of the structures keep consistent, a valid measurement datum under steady-state heat transfer conditions is transformed into a plurality of valid measurement data under transientconditions, and accordingly the problem of matrix singularity due to insufficient input information during multi-parameter identification can be effectively solved by the aid of the method; the inverse heat conduction problems can be solved, and accordingly the internal temperatures and the thicknesses of the related structures under the steady-state heat transfer conditions can be quickly and nondestructively measured in a non-contact manner by the aid of the method.

The invention relates to a device and method for in situ measuring steady-state heat transfer character of variable density fibrous. The device comprises a main force application device, a load-bearing positioning device, a digital camera device, a light measurement device, an intra-cavity pressure measurement device, a data acquiring card, a driving and control circuit, a data acquiring treatment and interface control module and a computer in the original patent, and further comprises improved components such as a push barrel measurement cavity, a fiber plug barrel, a lower measurement cavity, a heating control device, a heat testing device, a data acquiring card and a data acquiring processing module, wherein the data acquiring card and the data acquiring processing module are connected with the push barrel measurement cavity, the fiber plug barrel, the lower measurement cavity, the heating control device and the heat testing device. The testing method of the device comprises the steps of playing the effect of the force on the fibrous to change the density and the density distribution, playing the heating effect on the fibrous to generate a certain temperature difference between two ends of the fibrous, testing the temperature difference and heat fluxes at the two ends of the fibrous to obtain a heat conductivity coefficient and the heat resistance of the fibrous. The method and the device disclosed by the invention are high in measurement precision, convenient for sample preparation, short in testing time, wide in applicable range, and suitable for the in-situ measurement on the steady-state heat transfer character under a fibrous variable density condition.

The invention discloses an electrostatic atomizing and cooling capacity evaluation device with an adjustable nozzle space angle, belonging to the technical fields of heat exchange and cooling. The electrostatic atomizing and cooling capacity evaluation device comprises an electrostatic atomizing and cooling system and a critical heat flux and heat transfer coefficient measurement system, wherein the electrostatic atomizing and cooling system comprises a big fan-shaped disc, a small fan-shaped disc, an adjustable handle, a guide rail, a first sliding block, an injection pump, a silicone rubber tube and a bracket; the critical heat flux and heat transfer coefficient measurement system comprises a purple copper bar, a K-shaped thermocouple wire, a heat insulation sleeve, a box cover, a purple copper block, an electric heating bar, a graphite felt heat insulation tray, a second sliding block, a base, a supporting block, a graphite felt heat insulation supporting block, a guide block, a voltage meter, a variable resistor and a K-shaped thermocouple. According to the electrostatic atomizing and cooling capacity evaluation device, electrostatic atomization transient-state and steady-state heat transfer experiments can be carried out on the same device at different nozzle space angles, in different target distances and with different output voltages, heating powers and cooling medium fluxes of a high voltage static generator, and the critical heat flux and the heat transfer coefficient can be measured.

The invention discloses a simple and simple steady-state testing system for thermal conductivity of high thermal conductivity materials. During the test, the heating section is heated with constant power through the connection of the heating system and the electric heating film, the cooling system is connected with the cooling chamber to cool the cooling section at a constant temperature, and the data acquisition and processing system is connected with the thermocouple to complete the process of the tested high thermal conductivity material. Real-time acquisition and output of temperature. In addition, heat insulation materials are used to insulate the heating section and the insulation section of the tested high thermal conductivity material during the test, so that the heat is transferred along the length direction of the tested high thermal conductivity material, forming a one-dimensional stability of the tested high thermal conductivity material along the length direction. State-to-state heat transfer can realize a large temperature difference along the surface of the tested high thermal conductivity material under a small heating power, ensuring a certain test accuracy. The invention can solve the problems in the prior art that when testing the thermal conductivity of high thermal conductivity materials, the sample size is large, the heating power is large, it is difficult to implement, the test accuracy is low, and the thermal conductivity of the material cannot be obtained through a one-time test.