Constant Temperature Control System Research Articles

Experimental Study on Evaporation and Micro-Explosion Characteristics of Ethanol and Diesel Blended Droplets

In this study, the constant temperature control system of a heating plate was established, ethanol–diesel fuel with different proportions was prepared, and a series of experiments were carried out. The experimental system was used to observe, summarize, and analyze four evaporation and crushing modes of mixed droplets, which were explosion, liquid filament stretching, exocytosis, and ejection mode. The evaporation process of four kinds of mixed droplets in their life cycle was analyzed by normalizing the diameter square. It was proposed that the evaporation process of droplets could be divided into the following three stages: a heating stage, a fluctuating evaporation stage, and an equilibrium evaporation stage. It was also pointed out that the expansion, ejection, and micro-explosion of droplets were the causes of fluctuating evaporation. The concept of expansion and crushing intensity was put forward and the expansion and crushing intensity of ethanol/diesel mixed droplets with different proportions were calculated. The reasons why expansion and crushing intensity first increased and decreased with the increase in ethanol blending ratio were analyzed. Finally, the time proportion of ethanol–diesel mixed droplets in each evaporation stage was calculated, which explained that the time proportion of the instantaneous heating stage showed a parabolic law with the increase in ethanol content.

Fast and Precise Temperature Control for Axon Stretch Growth Bioreactor Based on Fuzzy PID Control.

A suitable environment is essential for successful long-term cell culturing in vitro. Too high or too low temperature will affect the growth of cells, so we need to maintain the constant temperature of the cell culture environment. Usually, cells are cultured in a cell incubator, and the constant temperature is provided by the cell incubator. Recently, we have developed a multi-channel axon stretch growth bioreactor for rapid acquisition of autologous nerve tissue. Since the motor and controller are placed in the incubator for a long time, the service life of the equipment will be shortened or even damaged due to high humidity and weak acid environment. In order to enable the axon stretch growth bioreactor to culture cells independently, we designed a constant temperature control system for the device. Firstly, the simulation results show that the fuzzy PID control reduces the overshoot and improves the traditional PID control with large overshoot and low control precision. Then, the two control algorithms were applied to the multi-channel axon stretch growth bioreactor by STM32F4 microcontroller. The experimental data show that the fuzzy PID control algorithm has good control effect and can meet the requirement of constant temperature of cell growth. Finally, nerve cells derived from human pluripotent stem cells were successfully cultured in a cell culture amplification chamber under a constant temperature environment provided by a fuzzy PID controller, and well-developed axons could be seen. In the future, we may transplant stretch growth axons into living organisms to repair nerve damage.

A constant temperature control system for indoor environments in buildings using internet of things

A constant temperature control system for indoor environments in buildings using internet of things

A constant temperature control system for indoor environments in buildings using internet of things

A constant temperature control system for indoor environments in buildings using internet of things

A convenient and practical triaxial coupled seepage testing apparatus for deep buried coal.

As the world's shallow coal resources are being depleted, resource development continues to progress faster. To explore the coupled hydromechanical behavior of coal reserves that are buried deep underground under high stress, complex seepage, high temperature, adsorption, and desorption, we have developed a triaxial seepage testing apparatus under multifactor coupling effect. The system consists of a high-pressure and high-precision servo control loading system, a triaxial core holder (TEMCO), a seepage dynamic control system, a low-field Nuclear Magnetic Resonance (NMR) test system, a constant temperature control system, and a data acquisition and monitoring system. This system is capable of applying high pressure and long-term loading for specimens under adsorption or desorption. In addition, both steady-state method and pressure transient methods can be applied, thus covering the entire range for coal reserves buried deep from ultralow permeability to high permeability and significantly shortening the testing time. The characteristics of pores and fractures in the specimens and their impacts on permeability can be quantitatively evaluated by the low-field NMR experimental technique. We conducted experiments to understand the evolution of permeability of different gases under different stress conditions and to study the impact of adsorption on pore size distribution. Our experimental results show that the performance of this system is stable and reliable, which allow it to reflect the coupled hydromechanical response of coal buried deep underground. We envision this apparatus has a wide range of application value and can provide a scientific experimental basis for improving the recovery of coalbed methane and geological sequestration of CO2 in the future.

First Prototype of a Cesium Oven Design for Negative-Ion-Source-Based Neutral Beam Injector at ASIPP

The RF-driven negative ion source has a steady state characteristic and will be a promising ion source for neutral beam injection (NBI) in the future. Cesium (Cs) injection is an efficient method to enhance the yield of negative ions during plasma discharge. In order to support the engineering and physical research in this field, the Cs oven prototype has been developed for negative ion source based neutral beam injector at ASIPP. This article presents the design details of a Cs oven system, including the constant temperature control system, the mechanical structure of Cs oven, and the surface ionization detector (SID). SID is a measurement method for the cesium flux in the nozzle. The experiment results of constant temperature control system show that the control accuracy and function meet the requirements of device operation. Meanwhile, the simulation analysis of Cs vapor concentration has been carried out in this paper. According to the simulation results, the graph of total Cs flux is given in the article, which presents the reference for the subsequent device testing.

Research on electric kettle temperature control system based on MATLAB/Simulink

Constant technology control has been widely used in modern agriculture and industry and daily life, control performance affects the safety, the industry productivity and product quality. Based on MATLAB/Simulink software, take the electric kettle as the control object, the simulation model of constant temperature control system is proposed in the paper, the PID controller is used to calibrate the system, and realize constant temperature control of electric kettle. The simulation results show that the PID controller is used to control temperature, which reduces the time of overshooting and adjusting, improves the control accuracy and system reliability, and has practical reference value.

Development of a special cell for optical and electrochemical measurements using 3D printing and modern electronic base

A special design of the measuring cell was proposed, which makes it possible to determine the optical and electrochemical characteristics of thin-film electrochromic electrodes simultaneously. Also, the proposed cell provides constant temperature control using a small-sized thermostating unit built on Peltier elements and digital boards of W1209 thermostats. The cell was made using 3D printing with ABS plastic by the fused deposition method (FDM), followed by a sealing stage using a solution of polymethyl methacrylate dissolved in dichloroethane. In the course of the research, the use of a green laser with a wavelength of 520 nm was substantiated. Separately, the linearity of optical readings, the dependence of the indicators of the optical characteristics measurement system on temperature, as well as the uniformity of electrolyte heating in the cell, were studied. In addition, the pattern of the electric field was determined, which was an indicator of the uniformity of the current density distribution on the measured electrode. The obtained dependences made it possible to assert that the characteristics of the cell and the measuring system as a whole are suitable for the stated research purposes. It was also shown that the cost of the cell, together with the optical measuring system and the constant temperature control system, is more than two times cheaper than simple electrochemical cells offered by manufacturers. The proposed algorithm for the development of the cell design, the approach to the selection of components, as well as the given technical details, allow us to manufacture measuring equipment for the specific goals of the researcher. In this case, the given schematic, structural, and hardware solutions can be used separately from each other

Research on Electric Kettle Temperature Control System Based on MATLAB/Simulink

Constant technology control has been widely used in modern agriculture and industry and daily life, control performance affects the safety, the industry productivity and product quality. Based on MATLAB/Simulink software, take the electric kettle as the control object, the simulation model of constant temperature control system is proposed in the paper, the PID controller is used to calibrate the system, and realize constant temperature control of electric kettle. The simulation results show that the PID controller is used to control temperature, which reduces the time of overshooting and adjusting, improves the control accuracy and system reliability, and has practical reference value.

Constant temperature control system of building energy system

Due to the poor effect of traditional systems on constant temperature control, the paper proposes to design an embedded continuous temperature control system in a dynamic, intelligent building. In the smart building, the thesis takes the building as the research object and uses the embedded technology to design the overall structure diagram of the system. The thesis aims at the output control module of the thermostat. It uses the Peltier effect to develop the thermocouple closed-loop and drives the semiconductor refrigeration device select. In the software part, the paper establishes a cross-compilation environment, transplants embedded kernels, and sets fuzzy rules for constant temperature control. The validity of the system design is verified through experiments. It can be seen from the experimental results that the system has a better thermostat control effect.

Thermal energy constant temperature control system of building energy system based on dynamic analysis method

If the intelligent building?s indoor environment?s constant temperature is accurately controlled, the comfort of the building can be improved. When we perform constant temperature control, there will be large fluctuations in the supply air temperature, which results in the traditional methods that cannot control the temperature within a reasonable range. Therefore, the paper proposes an optimal control method for the indoor environment constant temperature of intelligent buildings. In the IoT environment, we integrate the multi-agent technology to design the temperature fuzzy control structure, determine the input and output variables of the intelligent building temperature control system and its fuzzy set, use the dynamic analysis method to modify the fuzzy rules, and integrate it with bilinear The control algorithm builds a dynamic temperature control model for intelligent buildings to maintain the indoor temperature at the set value when the supply air temperature fluctuates significantly. This method makes up for the shortcomings that the current system cannot adapt to the intelligent building environment changes. The simulation results show that compared with the traditional algorithm, the improved algorithm can significantly improve the robustness of the intelligent building constant temperature control, and the temperature control stability is vital.

Dynamic performance and control strategy of CO2-mixture transcritical power cycle for heavy-duty diesel engine waste-heat recovery

Carbon dioxide mixture transcritical power cycle (CMTPC) is considered as a new promising technology for waste heat recovery (WHR), while there are still critical challenges arising from the transient fluctuations of heat sources when it comes to the heavy-duty diesel engines (HDDEs) applications. This paper presents a dynamic model of CMTPC systems, which is carefully validated against experimental data. Constant temperature, constant pressure and optimal control strategies are proposed to realize stable and optimal operation. The dynamic performance of the system with different control strategies is predicted under slow step change and transient change conditions. The results demonstrate that under slow step change conditions, the stability of optimal control system and constant pressure control system is better than that of constant temperature control system. In addition, the net power output keeps maximum under the optimal control because of the compromise between operating pressure and temperature. However, under transient conditions the control performance of optimal control is not as obvious as under slow step change conditions. Compared with open loop system, the improvement of system power by optimal control under slow step change is 2.31%, while that is only 0.07% under transient change condition. By contrast, it is found that the constant pressure control achieves the best power improvement of 0.58% under transient conditions because of the satisfactory control effect on operating pressure and relatively small fluctuations of expander inlet temperature. In a word, different control strategies behave obviously different performance under various conditions.

Constant temperature control system for indoor environment of buildings based on internet of things

In order to improve the stability of constant temperature control for indoor environment of buildings, a design method of constant temperature optimisation control system for buildings' indoor environment based on internet of things (IoT) is proposed. The system design is divided into two parts – the control algorithm design and the hardware structure design of the control system – to conduct the overall design framework analysis and functional component analysis of indoor environment constant temperature control system. The time-delay feedback error compensation method is adopted to optimise the design for temperature control law for indoor environment of buildings. The test results show that the minimum root-mean-square error of the designed constant temperature control system is 0.021, which significantly reduces the temperature error of the constant temperature control system, indicating that the system has good temperature output stability, strong adaptive adjustment ability and effectively improves the constant temperature control ability of indoor environment.

Constant Temperature Control System for Indoor Environment of Buildings Based on Internet of Things

In order to improve the stability of constant temperature control for indoor environment of buildings, a design method of constant temperature optimisation control system for buildings' indoor environment based on internet of things (IoT) is proposed. The system design is divided into two parts – the control algorithm design and the hardware structure design of the control system – to conduct the overall design framework analysis and functional component analysis of indoor environment constant temperature control system. The time-delay feedback error compensation method is adopted to optimise the design for temperature control law for indoor environment of buildings. The test results show that the minimum root-mean-square error of the designed constant temperature control system is 0.021, which significantly reduces the temperature error of the constant temperature control system, indicating that the system has good temperature output stability, strong adaptive adjustment ability and effectively improves the constant temperature control ability of indoor environment.

The Design of Closed-Loop Piecewise PID Constant High Temperature Control System

The Design of Closed-Loop Piecewise PID Constant High Temperature Control System

Design, Simulation, and Verification of a Heating and Stirring Device for Cold Patching Materials in the Plateau Cold Region of China

In the plateau cold region of China, the highway maintenance line is long, the maintenance fund is insufficient, the annual average temperature is low, the air is thin, the temperature difference between day and night is large, and the freezing and thawing cycle is frequent and intense. These conditions lead to the poor highway maintenance in the cold region of the plateau. At present, cold patching materials are commonly used for daily maintenance in the plateau cold region. Due to the low-temperature construction environment in the plateau cold region, the moisture of cold patching materials after demulsification is not easy to evaporate, the compaction effect is weak, re-freezing and thawing easily occur after the temperature rises, and the maintenance quality is low. In order to avoid the restriction of season and weather on highway maintenance in plateau cold areas and to solve the problem of poor maintenance and construction quality of cold patching materials in plateau cold areas in low temperature environment, this paper proposes a scheme of heating emulsified asphalt cold patching materials to a certain temperature and then constructing it, and designs a heating and stirring system, a constant temperature control system, a control system circuit and other parts according to the scheme requirements, finally completing the overall design of the heating and stirring device. Then, working parameters such as stirring motor power 2 kW and stirring speed 30 r/min are determined through theoretical calculation. To verify that the design is reasonable, we established a 3D model of the heating device by using ANSYS CFX fluid analysis software. Simulation analysis was carried out on the heating device, and the design parameters were optimized. On the basis of optimized parameters, production equipment of heating device prototype, and prototype field experiment, field experiment results show that the simulation and experimental results are in good fit and that the design parameters are reasonable. The results of this study can serve as a reference for highway maintenance in cold highlands.

Design on Monitoring and Controlling System of Blast Furnace Recovery of Waste

A constant temperature and variable flow control system was designed for that blast furnace slag is not continuous and water temperature largely fluctuated , which included hardware and software . Data acquisition module in the hardware part used Siemens S7-300 series PLC. The software part used Wincc and Step7 to realize system configuration and the data acquisition for respectively. The system is verified by experiments. The results show that the system has the characteristics of stable running, easy to operate and maintain. It can realize the function of real-time monitoring of residual heat in B. F. waste water to ensure that system can be run under the optimal conditions.

The constant temperature control system of multi-pass and die-less shear spinning by flame heating

In order to improve the formability of challenging materials, the innovative flame-heating integration into a spinning machine is proposed to apply new processing strategies for flame-assisted die-less shear and multi-pass metal spinning. The device mainly includes measurement system and control system. The calculating function of control system is designed to adjust the forming temperature according to the feedback of measurement system. TC4 and TA2 are used for shear spinning and multi-pass spinning to verify the feasibility and reliability of the system with the forming temperature 450 and 850 °C respectively. The temperature change during the process of spinning is recorded once a second by temperature sensors. Then the absolute values of mean relative deviations under two conditions are less than 5% by comparing measurement temperatures and preset temperatures. Furthermore, the result shows that the forming accuracy by adopting the system under two conditions is acceptable.

大功率半导体激光器驱动电源及温控系统设计

In order to solve the output wavelength and power stability of high power semiconductor laser, high power semiconductor laser constant current driver and temperature control system were designed. Deep negative feedback circuit was used to control the laser drive current, the analog Proportional-Integral (PI) circuit and constant current driver were adopted to control the working current of Thermoelectric Cooler (TEC), the laser working temperature can be kept accurately. The design can realize the linear adjustment of output current from 0-12.5 A, and has the function of current detection, over-current protection and Transistor-Transistor Logic (TTL) modulation. The control precision of the temperature control system can achieve 0.05℃. Temperature can be adjusted continuously and can be monitored in real time. Experiment results show that the design can guarantee the output current and temperature control stably, which satisfies the requirement of high power semiconductor laser.

The Research of Constant Temperature and Humidity Air-Conditioning System of Underground Cellar

Accordance with the high Precision control problem of constant temperature and humidity air-conditioning system of wine storage of large underground cellar and based on the cellar building construction features and the reasonable allocation of ducts and valves., this paper proposes the distributed intelligent temperature and humidity PLC control solution and designs a remote monitoring system and gives the test results. Actual operating results show that the use of distributed PLC control constant temperature and humidity control system with high efficiency, low energy consumption, remote operation of the file, and meet the environmental requirements of various types of wine storage.