2020 results about "Thermal fluids" patented technology

The invention relates to the field of liquid air energy storage, and discloses a liquid air energy storage and liquefied natural gas coupling efficient power generation device and method. The method comprises the steps that an air liquefaction circulation loop purifies, compresses and cools ambient air and then expands and decompresses the ambient air to obtain liquid air, and the liquid air is transmitted to an air power generation circulation loop; generated air compression heat is stored in the heat storage unit; the air power generation circulation loop generates power through expansion of received liquid air, and generated cold energy is stored in a cold storage unit; the LNG vaporization supply loop pressurizes, evaporates and gasifies liquefied natural gas and then supplies the liquefied natural gas to a user side, generated cold energy is stored in a cold storage unit or directly supplied to the air liquefaction circulation loop, and meanwhile gaseous natural gas naturally released by an LNG tank is collected and conveyed to a combustion chamber. The high-grade heat energy utilization loop conducts heat conduction oil circulation, low-grade heat energy and high-grade natural gas combustion heat energy of the heat storage unit are recycled in sequence, high-grade heat energy is transmitted to the air power generation circulation loop, and heat conduction oil returns to the initial state to continue circulation after releasing the heat energy.

An aircraft system is provided. The aircraft system includes: a gas turbine engine; a fuel system having a fuel tank and a fuel delivery system fluidly connecting the fuel tank to the gas turbine engine; an electric drive assembly including a component module; and a thermal management system including: a thermal fluid loop; a heat source heat exchanger in thermal communication with the component module and the thermal fluid loop; an airflow heat sink heat exchanger in thermal communication with the thermal fluid loop and further configured to be in thermal communication with a cooling airflow during operation of the gas turbine engine; and a fuel heat sink heat exchanger in selective thermal communication with the thermal fluid loop, the fuel tank, or both, the fuel heat sink heat exchanger in fluid communication with the fuel tank independently of the fuel delivery system during at least a first operating condition.

The invention relates to the technical field of temperature control, in particular to an enzyme reaction kettle self-adaptive temperature control system and method, and the system comprises a temperature detection module, a temperature control module, a heat conduction oil flow control module and an automatic regulation and control module; temperature data of a reaction kettle are collected in real time through a temperature detection module, a temperature control module adjusts parameters based on a PID algorithm and fuzzy logic to generate a control instruction, and a heat conduction oil flow control module adjusts flow by combining double-closed-loop cascade control with a feedforward compensation algorithm, so that thermal inertia lag is shortened. And the automatic regulation and control module generates optimized process parameters based on a reaction kinetic model and a genetic algorithm, and dynamically adjusts a temperature set value. The control method comprises the steps of temperature data acquisition, PID control instruction generation, conduction oil flow coordinated regulation, process parameter optimization and the like. The problems that in the prior art, temperature control precision is insufficient, conduction oil flow control is not accurate enough, and technological parameters cannot be automatically regulated and controlled are solved.

The invention relates to the technical field of hydraulic systems, in particular to a hydraulic and thermal fluid dynamic lubrication calculation model and an optimization method, comprising the following steps: S1, modeling a multi-scale heterogeneous system; s2, carrying out heat-friction-viscosity synergistic effect modeling; and S3, dynamic boundary lubrication and lubricant behavior prediction. According to the method, by integrating nanoscale, mesoscale and macroscopic level lubrication system modeling, physical phenomena on different scales and interaction of the physical phenomena are comprehensively captured, and the step covers multiple aspects of multi-scale heterogeneous system modeling, nanoscale lubrication behavior modeling, macroscopic fluid field and structure field coupling and the like; high-precision predictive capacity and systematic thermal management are achieved by combining multiple physical fields such as heat, friction, viscosity and fluid dynamics, through collaborative modeling of multiple scales and multiple physical fields, the accuracy and stability of a lubricating system are improved, a solid theoretical basis is provided for optimization design, and the method is suitable for popularization and application. And stable operation in high-load and high-temperature environments is ensured.

A thermal management system includes a thermal circuit having a thermal transport bus with a thermal fluid flowing therethrough. The thermal transport bus includes first and second bus segments. First and second thermal loads are on the first and second bus segments, respectively, and have different first and second inlet temperature requirements. The thermal management system includes a plurality of heat exchangers in thermal communication with the first and second thermal loads. The heat exchangers include a first heat exchanger and one or more second heat exchangers. The first heat exchanger is on one of the first or second bus segments for rejecting heat to engine fuel. The thermal fluid is split between each of the first and second bus segments such that only a portion of the thermal fluid flows through the first heat exchanger to accommodate the different first and second inlet temperature requirements.

The invention discloses a laser cladding preparation method for improving the wear resistance of a cladding layer by doping tungsten carbide. According to the method, cladding process parameters are preliminarily obtained based on finite element heat flow analogue simulation, cladding layer preparation is carried out, cladding quality characterization is carried out to obtain the optimal cladding process parameters, and finally the cladding layer with the wear-resistant characteristic is obtained. The method comprises the following steps: firstly, constructing a heat flow coupling three-dimensional model, carrying out grid division, establishing a heat source model, defining thermophysical parameters of tungsten carbide (10-15%) nickel alloy composite powder and a matrix, and determining simulated boundary conditions; setting a multi-factor process parameter combination to carry out numerical simulation calculation, and determining laser processing process parameters of laser power, scanning speed and light spot diameter; preparing a cladding layer on the surface of the nodular cast iron by using tungsten carbide (10-15%) nickel alloy composite powder through a laser cladding method; and carrying out microscopic morphology and microhardness experiments to carry out quality analysis verification on the cladding layer, determining the optimal process parameters of laser power, scanning speed and light spot diameter when the cladding layer has no obvious defect morphology and the hardness is higher than that of the raw material, and obtaining the laser cladding preparation method for improving the wear resistance of the cladding layer by doping tungsten carbide. The invention provides a new research method and a high-quality preparation approach for improving the wear resistance of the cladding layer by tungsten carbide, and can be widely applied to the fields of strengthening and repairing mining machinery, aerospace parts and the like.

The invention relates to the field of blast furnace pulverized coal preheating. A blast furnace pulverized coal preheating system comprises a coal injection workshop, a nitrogen heater, a common pulverized coal heater, a compressed nitrogen tank, a blast furnace, an oil storage tank, an expansion tank, a waste heat exchanger, a heat conduction oil pump, a PLC control system and a sound-light alarm device. Pulverized coal discharged from a coal injection workshop is heated in a common pulverized coal heater through waste heat of a blast furnace, and the heated pulverized coal enters the blast furnace to be combusted. The combustion characteristic of the preheated pulverized coal is remarkably improved, and the pulverized coal can be quickly combusted after entering a main combustion chamber of the blast furnace, so that the conventional three-section combustion process of heating, ignition and combustion is broken through.

The embodiment of the invention provides a heat conduction oil heating temperature control system and method. The system comprises a first detection module, a temperature control module, a circulating pump, a waste heat recovery module, a plurality of segmented heat conduction oil pipelines, heating modules corresponding to the heat conduction oil pipelines and a second detection module. The first detection module sends the environment temperature to the temperature control module; the temperature control module calculates the initial heating power corresponding to each heat-conducting oil pipeline, contains the initial heating power in a heating instruction and sends the heating instruction to the corresponding heating module; the circulating pump drives the heat-conducting oil to each heat-conducting oil pipeline; the heating module heats the heat utilization equipment according to the initial heating power; the second detection module sends the heating temperature of the conduction oil pipeline corresponding to the current time period to the temperature control module; the waste heat recovery module calculates the waste heat utilization rate and sends to the temperature control module; and the temperature control module calculates to-be-adjusted heating power required by the next time period, contains the to-be-adjusted heating power in a heating instruction and sends the heating instruction to the corresponding heating module for subsequent heating temperature control, so that the heating temperature control precision of the heat-conducting oil is improved, and the energy consumption is reduced.

A multi-way valve adapted to control a flow of fluid to different thermal fluid circuits includes a valve housing, a valve flow controller, and a sealing system. The valve flow controller is arranged in the valve housing to control flow through the valve housing. The sealing system is configured to seal between the valve housing and the valve flow controller.

The utility model discloses a magnesium-based solid hydrogen storage device which comprises a tank body, an upper cover, a hydrogen pipe and a heat-conducting oil pipe, the tank body is of an upward opening structure and comprises an outer tank and an inner tank, an oil guide inlet is formed in the top of the outer tank, an oil guide outlet is formed in the bottom of the outer tank, an oil guide channel is formed between the outer tank and the inner tank, and a magnesium-based solid hydrogen storage material is filled in the inner tank; the upper cover covers the tank body; the hydrogen pipe penetrates through the upper cover and is communicated with the inner tank, and a plurality of air holes are formed in the hydrogen pipe; the heat conduction oil pipe penetrates through the upper cover and extends into the inner tank. An oil guide channel and a heat-conducting oil pipe are arranged, heat-conducting oil is continuously added in the hydrogen absorption and desorption process, the internal temperature of the tank body is regulated and controlled, the magnesium-based hydrogen storage material is in a high-temperature environment through internal and external combination, the temperature of the inner tank is kept stable, and the hydrogen absorption and desorption reaction rate is increased; and a plurality of air holes are formed in the surface of the hydrogen pipe, so that hydrogen fully reacts with the magnesium-based hydrogen storage material in each area of the inner tank body, and the hydrogen storage performance is enhanced.

The invention relates to the technical field of solar thermal power generation, and discloses a mirror field and heat absorber cooperative control method and system, and the system comprises a simulation coupling module which determines a light incident angle based on irradiation data and a sun position model, builds a heliostat model in a simulation environment, simulates a three-dimensional thermal fluid, determines a heat absorber model, and controls the heliostat model and the heat absorber model; the control strategy module determines a control strategy according to the heliostat model and the heat absorber model, the control strategy module integrates a plurality of intelligent control algorithms, predicts a future state and adjusts control input based on the models, and the environment simulation module provides a training scene and a fault working condition scene of extreme weather and sets the extreme weather as a plurality of risk levels. The data analysis module collects and stores operation data, the operation state and performance indexes are displayed through a visual interface, control input is adjusted for the actual working condition and the future state on the basis of a dynamic model, and good control stability is achieved.

The invention relates to the technical field of microorganism culture, and discloses a microorganism culture tank device which comprises a culture tank, a concave observation area is arranged in the center of the top of the culture tank, a central culture area surrounding the observation area is arranged in the culture tank, an oil path temperature control area wraps the culture tank, and a double-helix heat conduction oil path is integrated in the oil path temperature control area. Through the cooperation of the uniform distributor and the distributed simulated liquid conveying unit, the gas-liquid proportion and fluid distribution can be accurately regulated and controlled, the physical and chemical conditions in the deep sea or extreme environment are simulated, the constant-temperature precision of + / -0.005 DEG C is realized through the double-helix heat conduction oil way, the low-temperature environment is stably maintained, and the real thermodynamic conditions of deep-sea sediments are simulated; the device meets the sensitive requirements of different microorganisms on temperature, and has the characteristics of high practicability and capability of simulating a dynamic fluid environment of deep sea.

An aircraft system includes an electrified powertrain having a first power module and a second power module. The aircraft system further includes a thermal management system having a thermal fluid loop for conveying a thermal fluid. The first power module and the second power module are in thermal communication with the thermal fluid loop. The thermal management system further includes a heat exchanger in thermal communication with the thermal fluid loop upstream of the first power module and the second power module such that the thermal fluid from the heat exchanger is partitioned between the first power module and the second power module.

The invention discloses a pure electric vehicle heat pump type whole vehicle thermal management system and method, and relates to the technical field of new energy vehicle thermal management, and the method comprises the following steps: constructing a combined twin system of thermal fluid, structural vibration and acoustic fluctuation, collecting pressure waves and vibration phases by using an array sensor, forming a steady state baseline spectrum and a transient state baseline spectrum, and calculating the temperature of the steady state baseline spectrum and the transient state baseline spectrum; and a unified reference is established. According to the method, a combined twinborn system of thermal fluid, structural vibration and acoustic fluctuation is constructed, the dynamic characteristics of pulsating waves are accurately monitored, and instability early warning is carried out by using a phase locking tracking method. Through pipeline topology reconstruction and segmented damping link design, a self-adaptive pulsation buffer zone is introduced, and pulsation energy is effectively absorbed. And in combination with a multi-target control law and a time reflection mirror cooperative regulation strategy, refrigerant flow is accurately controlled, pulsation energy is actively counteracted, and stable operation of the system is guaranteed. Through the innovative design, the stability of a heat management loop is improved, the fault risk caused by pulsation is reduced, and the cooling efficiency and safety are improved.

The invention provides a conduction oil boiler system optimization control method and system based on an adaptive algorithm. The method comprises the steps of data acquisition, data preprocessing, model training, parameter optimization and real-time control. The system comprises a sensor network, a data processing module, a model training module, an optimization calculation module and a control execution module. Boiler operation data are collected in real time through a sensor network, a combustion boiler natural gas dynamic prediction model and a circulating pump efficiency optimization model are constructed after preprocessing, parameters such as the number of boilers, the circulating pump frequency and the oil supply temperature are optimized through an adaptive differential evolution (ADE) algorithm, and finally closed-loop adjustment is achieved through a control execution module. According to the method, the data-driven modeling technology and the self-adaptive optimization capability are utilized, so that system parameters can quickly respond to process demand changes, the heat efficiency is remarkably improved, the energy consumption is reduced, the temperature fluctuation is reduced, the operation and maintenance cost is optimized, and the operation performance and the economical efficiency of the heat conduction oil boiler system are comprehensively improved.

The invention relates to the technical field of heavy oil thermal recovery, in particular to a multi-element thermal fluid generator system operation control system which comprises a data acquisition module used for acquiring working parameters of a multi-element thermal fluid generator during working, and the working parameters comprise multi-element thermal fluid parameters, working pressure, working temperature, water flow, gas amount and air flow; the trend identification module is used for identifying change trends of the working parameters at different positions, selecting the change trends of the corresponding working parameters according to different types of abnormal states when the working parameters are in abnormal states, and judging fault positions and processing measures of the working parameters according to the change trends; the work adjusting module is used for acquiring the parameter proportion and the distribution quantity of the working parameters according to the fault positions of the working parameters, and setting adjusting factors of the working parameters according to the parameter proportion and the distribution quantity of the working parameters; the stability, reliability and operation efficiency of the system are improved, and the maintenance cost is reduced.

A multi-way valve adapted to control a flow of fluid to different thermal fluid circuits includes a valve housing, a valve flow controller, and sealing systems. The valve flow controller is arranged in the valve housing to control flow through the valve housing. The sealing systems are configured to seal between the valve housing and the valve flow controller.

The invention relates to the technical field of temperature control, in particular to an intelligent solar heat supply temperature management and adjustment system which comprises a thermal distribution modeling module, a thermal equilibrium optimization module, a fluid heat transfer design module, a dynamic layout adjustment module and an environmental factor coupling module. According to the method, through calculation based on solar radiation intensity and heat absorption parameters, a thermal distribution field is accurately established, a dynamic optimization basis is provided, thermal gradient differences are reduced, heat distribution balance is achieved, and through optimization of heat absorption coating covering density and pipeline layout, the heat energy transfer efficiency is improved, and local overheating and energy loss are reduced; pipeline distribution and fluid flow rate optimization are combined with heat transfer oil heat exchange performance, heat transfer efficiency is enhanced, radiation angles and layout parameters are dynamically adjusted, the solar energy absorption rate of the heat collection device is improved, output parameters are adjusted in real time in combination with environment temperature and wind speed, the capacity of the system for adapting to complex climate conditions is improved, and efficient and stable heat energy utilization is achieved.

The present invention discloses a high and low temperature performance test box based on a mixed refrigerant and a control method, including a box body, a refrigeration chamber, a heating chamber, an electric refrigeration device, an electric heating device, and a support roller. The upper part of the box body is provided with a refrigeration chamber that penetrates forward, and the bottom is provided with a heating chamber that penetrates forward. The refrigeration chamber is provided with an electric refrigeration device, and the electric refrigeration device uses a mixed refrigerant for refrigeration, and the heating chamber is provided with an electric heating device. During the temperature test of the present invention, the heat transfer oil in the heat preservation tank is refluxed into the heat dissipation pipe by controlling the lifting mechanism to rise, and then the electric control stop valve is controlled to be cut off, and the electric heating device and the electric refrigeration device are controlled to be powered on to work. At this time, the heat transfer oil in the heat dissipation pipe can absorb the heat generated by the electric heating device, but the heat will not be dissipated to the outside to cause waste, but will be retained in the heating chamber to heat the object being tested.

Conduction oil is adopted as a heat-carrying medium of a boiler tail flue gas heat recoverer and an external air pre-heater, flue gas low-temperature corrosion is effectively avoided, meanwhile, efficient recycling of waste heat of flue gas of the steam boiler is achieved, and the steam boiler is compact and convenient to install and arrange. The composite heat-carrying type steam boiler is characterized in that the steam boiler adopting water as a heat-carrying medium and the heat-conducting oil boiler adopting heat-conducting oil as a heat-carrying medium are combined, and the composite heat-carrying type steam boiler has a good application prospect.

The invention discloses an oil heat conduction emulsification tank based on the Internet of Things, and relates to the technical field of stirring, the oil heat conduction emulsification tank comprises a rotating shaft, blades, hollow adjusting blocks, a heating pipe, a cooling pipe and other assemblies, the flow can be adjusted in a deformable mode through a piezoelectric material, emulsification stirring and accurate temperature control integration is achieved, and unique double-cone through holes in the blades are matched with a partition plate structure; the materials are fully dispersed and mixed in the extrusion-expansion process, so that the emulsification efficiency is remarkably improved; through the hollow design of the rotating shaft and the blades, heat conduction oil or cooling liquid circularly flows along a preset path, the temperature can be rapidly increased and decreased, the temperature can be flexibly controlled in a partitioned mode, the controller has the functions of data collection, the Internet of Things and remote monitoring, temperature information collected by multiple sensors in the tank can be processed in real time and fed back and adjusted, and efficient, energy-saving and intelligent production is achieved.

The invention discloses a shell-and-tube heat exchanger, which relates to the technical field of heat exchangers and comprises a shell, a first end cover, a second end cover, a plurality of heat exchange tubes and fluid guide tubes, the shell is of a cylindrical structure, a cold fluid inlet and a cold fluid outlet are formed in the side walls of the two ends of the shell respectively, a first end cover and a second end cover are arranged at the two ends of the shell, tube plates are arranged between the first end cover and the shell and between the second end cover and the shell, a hot fluid inlet is formed in the first end cover, and a hot fluid outlet is formed in the second end cover. The heat exchange tubes are arranged in the shell, the two ends of each heat exchange tube are connected to the tube plate so as to communicate with the first end cover and the second end cover, and a plurality of annular fins of an annular structure are arranged on the outer circumference of each heat exchange tube at intervals in the axial direction of the heat exchange tube; the fluid guide pipe is inserted into the hot fluid inlet and extends in the axial direction till abutting against the inner wall of the first end cover, and a plurality of through holes are formed in the side wall, close to the heat exchange pipe, of the fluid guide pipe. Therefore, the heat exchange efficiency of the heat exchanger can be improved.

According to the composite cascade power generation system coupled with the multi-stage different turbines, through coupling of high-pressure supercritical heat absorption and low-pressure subcritical heat absorption of a working medium, a dual-pressure heat absorption organic Rankine cycle is formed, the working efficiency and the heat utilization rate of the system are synchronously improved, and # imgabs0 # loss is reduced; the temperature matching effect of circulation and heat source fluid is effectively improved; according to the system, the design of coupling multi-stage different turbines is adopted in the expansion power generation process, the system can better adapt to the expansion ratio and flow characteristics of a working medium under the same pressure level, higher expansion efficiency can be achieved by conducting cooperative expansion on the turbines at all stages, and therefore efficient gradient utilization of medium-low-temperature heat energy from water, flue gas, heat conduction oil and the like is achieved; and efficient operation of the system can be ensured under all working conditions. On the basis, the invention further provides a composite cascade power generation method executed by using the system.

The processing equipment comprises a screw extruder, a feeding mechanism located at the top end of the screw extruder, a heat conduction mechanism located on the outer side of the screw extruder, an upper mold body and a lower mold body, the upper mold body and the lower mold body are located at the output end of the screw extruder, and the upper mold body and the lower mold body are combined. A mold supporting frame is supported at the bottom end of the lower mold body, and the bottom end of the mold supporting frame is fixedly connected with a base. The heat conduction mechanism comprises a heat pipe body and a cold pipe body, the heat pipe body is filled with heat conduction oil, the cold pipe body is filled with cooling liquid, and a plurality of hollow heat conduction blocks are connected between the heat pipe body and the cold pipe body at the same time. The enhanced polypropylene engineering plastic processing equipment and the preparation method thereof disclosed by the invention have the effects of guaranteeing the melting requirement, the fluidity, the mixing property and the finished product quality of raw materials in the feeding process, simultaneously playing a role in saving the cost, avoiding chilling of a mold in the cooling process and effectively protecting the mold.

A method of operating a thermal system implementing a ground-source heat pump includes receiving design parameters associated with a design of the thermal system and receiving one or more measurement inputs associated with a flow of a thermal fluid through a borefield of a ground heat exchanger. The method further includes, based on the measurement inputs and the design parameters, predicting one or more predicted thermal values of the thermal fluid using a forward model. The method further includes predicting one or more predicted borefield parameters of the borefield based on inverting the forward model. The method further includes monitoring the thermal system based on the predicted borefield parameters.

The invention discloses an aluminum alloy flat cable for a new energy automobile, and relates to the technical field of power cables, the aluminum alloy flat cable comprises an aluminum alloy solid conductor, the outer side of the aluminum alloy solid conductor is provided with a composite insulating layer, the composite insulating layer is internally coated with an aerogel thermal insulation layer, the inner side of the aerogel thermal insulation layer is provided with a limiting center groove, and the inner side of the aerogel thermal insulation layer is provided with a limiting groove. A heat conduction silica gel sheet is clamped to the inner side of the limiting center groove, and a center connecting sleeve is connected to the middle of the heat conduction silica gel sheet. Heat in the flat cable is directionally transferred through circulation of heat conduction oil in the flow guide outer pipe and the backflow inner pipe; the flat cable ensures that the interior of the flat cable can be kept in a proper temperature range in the using process, effectively prevents the situation that heat generated in the working process of the flat cable is randomly diffused to cause abnormal temperature rise of peripheral electronic components to affect normal use, and ensures that the flat cable does not affect normal use of an automobile in the using process. And the use safety of the flat cable is effectively improved.

The invention discloses a heat energy cyclic utilization control system and method for a copper-clad plate factory, and relates to the technical field of heat energy cyclic utilization. The heat energy cyclic utilization control system for the copper-clad plate factory comprises a heat energy circulation module, wherein high-temperature waste gas is introduced to perform efficient countercurrent heat exchange with low-temperature high-medium heat-conducting oil; the temperature-pressure dynamic model building module is used for building a temperature-pressure coupling function according to the thermal expansion and phase change characteristics of the medium and building a temperature-pressure dynamic model in combination with the basic equation and the temperature-pressure coupling function; the temperature and pressure coupling optimal control sequence determination module is used for solving an optimal control sequence in a prediction window through a rolling optimization algorithm; and the heat energy utilization module is used for inputting the high-temperature and high-medium heat conduction oil obtained by heating in the heat energy circulation module into a plurality of heat utilization devices according to the optimal control sequence. According to the method, the optimal control sequence in the prediction window is solved through the rolling optimization algorithm to dynamically adjust the operation parameters of the system, and the problem that the heat energy circulation efficiency is reduced in the prior art is solved.

The utility model discloses a pilot plant for producing fulvic acid by a pyrolysis method. The pilot plant comprises a conduction oil boiler, a grinding machine, a reaction kettle, a sleeve cooler, a buffer tank, a circulating cooling tower and a circulating cooling water pump, wherein the heat-conducting oil boiler is circularly connected with the reaction kettle; the grinding machine is sequentially connected with the reaction kettle and the buffer tank; the sleeve cooler is arranged on a pipeline between the reaction kettle and the buffer tank in a sleeving manner; the sleeve cooler is further connected with a circulating cooling tower, a circulating cooling water pump and a buffer tank in sequence; and the buffer tank is also respectively connected with the sleeve cooler and the circulating cooling tower.

A system for operating at least a pair of pumps using a driver. The driver can be coupled to a first portion of a first drive shaft that is not positioned in within an interior area of a thermal fluid tank of a first thermal circuit. A magnetic coupling can couple the first portion to a second portion of the first drive shaft that is within the thermal fluid tank. Rotational displacement of the first portion of the first drive shaft can be translated, via the magnetic coupling, to the second portion of the first drive shaft to drive a first fluid pump. The first portion of the first drive shaft can also be coupled to a second drive shaft by a clutch, the second drive shaft being used to operate a second fluid pump that provides a force for circulating a second thermal fluid of a second thermal circuit.