4 results about "Heat measurement" patented technology

This invention relates to the field of aircraft fire resistance testing technology, and discloses a device, system, and method for acquiring the surface heat flux density of a fire-resistant test specimen. The system initialization includes: total heat flux measurement (obtaining the theoretical total heat flux value q0); actual pure radiative heat measurement (setting a glass cover around the heat flux sensor without changing its position, shielding convective heat through the glass cover, and then collecting the theoretical radiative heat flux value q1 measured by the heat flux sensor); and multiplying the pre-measured emissivity of the test specimen surface by the theoretical radiative heat flux value q1 to obtain the actual pure radiative heat flux value q. r Actual heat flux calculation: Actual convective heat value q c The actual heat flux q is obtained by subtracting the theoretical radiative heat flux q1 from the theoretical heat flux q0. a Equal to the actual pure radiative heat flux value q r and actual convective heat value q c The sum of radiative heat and convective heat is achieved through precise measurement of these two heat sources under actual aircraft fire conditions, providing high-fidelity, multi-scenario, and highly consistent thermal flow data for twin experiments.

This invention relates to an online system for determining flue gas thermal energy and a method for assessing its recovery value, belonging to the field of flue gas heat measurement and heat recovery technology. It solves the problem that existing methods cannot achieve online, real-time, and direct measurement of flue gas thermal energy. The system includes a flue gas parameter measurement unit, a signal acquisition and processing unit, and a thermal energy calculation and display unit. The flue gas parameter measurement unit includes a flue gas acquisition chamber, a flue gas temperature sensor, an ambient temperature sensor, and a flow measurement device. The signal acquisition and processing unit calculates the flue gas heat flow and waste heat quality using the received ambient temperature, flue gas temperature, and flue gas flow rate. The thermal energy calculation and display unit calculates and displays the real-time thermal energy using the received heat flow and waste heat quality. This invention also provides a method for assessing the recovery value based on real-time flue gas thermal energy, determining the waste heat recovery value by comparing the real-time thermal energy value with the critical thermal energy value. This invention is applicable to the assessment of the thermal energy value and recovery value of materials after combustion.

The present application belongs to the field of hot water tank heat measurement, discloses a kind of effective capacity determination method of hot water tank added in cogeneration unit, and the effective capacity of hot water tank can be accurately determined according to real working condition by step-by-step quantitative calculation of key parameters such as heat load, peak shaving duration, heat storage efficiency and supply and return water temperature difference.First, by quantifying the average heat load of the heating period and the typical peak shaving or peak duration, the heat storage demand can be closely matched with the actual operating load, avoiding the use of traditional estimation method with large safety factor, reducing the capacity configuration from the source. The present application introduces the heat loss parameter of the hot water tank, and includes the inevitable heat loss in the energy storage process into the calculation, so that the final effective daily heat storage is closer to the real available value, thereby avoiding the insufficient effective capacity caused by ignoring the loss and improving the sustainable heating capacity of the unit during peak shaving and peak period.

The application provides a heat measurement switch loss circuit and method suitable for a bottom heat dissipation GaN device, in which the drain of a to-be-measured GaN device T1 and the drain of an auxiliary GaN device T3 are connected to the positive electrode of a voltage source V DC , the source of T1 is connected to the drain of an auxiliary GaN device T2, the source of T3 is connected to the drain of an auxiliary GaN device T4, the sources of T2 and T4 are both connected to the negative electrode of the voltage source V DC , a first node N1 is included between the source of T1 and the drain of T2, a second node N2 is included between the source of T3 and the drain of T4, the two ends of an inductor L are respectively connected to N1 and N2, and a capacitor C DC is connected in parallel to the voltage source V DC . For the bottom heat dissipation to-be-measured GaN device T1, the application selects the top heat dissipation auxiliary GaN devices T2, T3 and T4 when testing by using the heat measurement switch loss circuit, so that most of the loss heat of T1 is on the PCB, and the heat loss measurement precision of the to-be-measured GaN device T1 is improved.