Overview of electric pump units for spacecraft thermal control systems

The paper reports a brief description of spacecraft operating conditions, the main reasons of heating and thermal gradient appearance and need to reassign the thermal energy. Active thermal control systems and their advantages are considered, spacecraft for which the use of this type of thermal control systems is a priority. The electric pumping unit is pointed as a key unit of active thermal control systems. The electric pump unit is considered from the as the electromechanical system, its key elements are pointed. A description of the preferred pump types is reported and the types of active thermal control systems are briefly discussed. The foreign and domestic operating experience of spacecraft electric pumping units, the features of their designs are considered, the most common types of key elements are determined. Based on the results of the review, it is concluded that the most relevant layout of the electric pump unit is a centrifugal electrical pump with a brushless DC motor and hydrodynamic bearings. It is also indicated that the electric pump unit is a product with a long lifetime, which complicates the task of monitoring the technical condition in order to prevent failure.

Protection of precision spacecraft equipment from internal sources of vibration

The work is devoted to the protection of a spacecraft from the influence of unacceptable internal vibration sources. The urgency of reducing the vibration activity on board the spacecraft to improve the accuracy of the target equipment is indicated. A particular problem of vibration protection of the spacecraft platform from a vibration source – an electric pump unit of a liquid thermal control system – is being solved. The basic requirements for electric pump unit vibration protection have been determined. Possible ways to reduce the level of vibration excited by the electric pump unit on the surface of the spacecraft fixation are considered. Particular attention is paid to such vibration protection methods as damping and vibration isolation, implemented by installing special vibration protection devices between the source (electric pump unit) and the object (spacecraft) – vibration isolators and vibration dampers. The principles of operation of vibration dampers and vibration isolators, the most common materials for vibration dampers are described. Examples of constructive solutions for linear single-axial vibration isolators are considered, recommendations for the use of promising products are developed. Particularemphasis is placed on the use of metal rubber as a material for vibration isolators. With regard to a specific design of electric pump unit, a diagram of the spatial structure of vibration isolation is proposed. Formulas for calculation are given in detail, a mathematical model of the vibration isolation system is developed. The procedure for calculating the parameters of the system has been formed. Based on the model, the maximum possible level of vibration suppression in the mid-frequency region was determined. Minimum required number of operable pixels was identified for monitoring the water surface with sufficient accuracy and reliability.

Design of Automatic Watering and Humidity Systems Based on Internet of Things for Screenhouse

<p class="Abstract">Central Bureau of Statistics <span lang="EN-GB">reports that the population in Indonesia continues to increase every 10 years. The more the population swells, the greater the need for food. To meet the community's need for food availability, there are several agricultural obstacles such as growth criteria that are not by the type of commodity. Air temperature, humidity and intensity of water supply are included as criteria for plant growth (Budiman and Saraswati, 2005). Erratic weather changes make farmers unable to guarantee production results with good quality_, and quantity. This research is designed using a tool that has been integrated with the </span>I<span lang="EN-GB">nternet of </span>T<span lang="EN-GB">hings system embedded in a raspberry pi as the overall processing core</span> [1]<span lang="EN-GB">. In addition to the raspberry pi, there are also several sensors as real condition readings, several relays as an electric pump controller and a solenoid valve as an electrical faucet controller, </span>and <span lang="EN-GB">these components will be connected</span><span lang="EN-GB">with the ESP8266/NodeMcu module using a wifi connection. The data read by these sensors is displayed on the smartphone screen as a monitoring function in real-time and also the user can directly take action using the remote control, both automatic actions using machine learning or manual action.</span><span lang="EN-US">This sophisticated screenhouse can perform irrigation actions and temperature regulation automatically without having to do direct monitoring every time. The use of this system in agriculture allows the owner to not need to do direct monitoring by coming to the screenhouse, users can simply monitor using a smartphone connected to the </span>I<span lang="EN-US">nternet network.</span><span lang="EN-US">The application of this system can carry out watering actions and regulate the temperature in the screenhouse room automatically according to the aspects of good growth criteria for plants. Like controlling the microclimate in the screenhouse. <em></em></span></p>

The Portable Fuel Transfer Pump Control System of Android Based for The Fuel Filling Effectiveness of Penerbad’s Helicopter

– The task of Army Aviation Operations is carried out in remote areas where airport services are still minimal, the process related to refueling for pilot helicopters is an obstacle in carrying out the pilot's main tasks. So, we need tools to make the process more effective. This research uses a method that will obtain quantitative data for research to prove the hypothesis. The method is known as the Development Life Cycle Waterfall Diagram and experimental research. Currently still using a hand pump, therefore it is necessary to have a tool that is portable and uses an electric pump. specifically for fuel which is controlled by Arduino and the android application as input for a filling command and can store charging data. In this case the tool system uses supporting components, namely batteries, Bluetooth hc 05, 5v relays and flow sensors. With the research on portable pump tools, the process can be more efficient than hand pumps. When refueling the helicopter, it is enough to enter the charging value from the android application, the charging is already running, and the charging data is stored in the android file.

Regulation of the temperature of an individual heat point by changing the speed of the asynchronous motor

THE PURPOSE. To develop and investigate a mathematical model of an operating object – an individual heat point with two methods of controlling the temperature of the coolant. In the first case, the control of the temperature of the coolant is considered, with the help of a control valve installed on a real object. In the second case, a more reliable and less energy-consuming solution is proposed – replacing the control valve with a frequency- controlled electric drive operating according to the proposed optimal algorithm. METHODS. When solving this problem, the method of computer simulation modeling, implemented by means of Matlab Simulink, was used.RESULTS. The article deals with the problems that arise during the operation of an individual heating point. Possible solutions to the problem associated with the failure of the control valve are given. A solution for regulating the temperature of the coolant is proposed, based on the use of a frequency-controlled electric drive of the electric pump. To implement the proposed solution, no redevelopment of the premises is required, only the installation of a frequency converter on the pump already available in the device of an individual heat station is necessary. CONCLUSION. The conducted research has a practical focus, since the proposed solution is implemented at the existing facility. The use of a frequency-controlled electric drive of a centrifugal pump made it possible to increase the reliability of the existing facility. The results obtained during the simulation allow us to draw a conclusion about the feasibility of using the proposed solution.

Best Practices in Development and Production Optimization of Offshore Low Permeability Reservoir

The development effect of low permeability reservoirs of offshore Shahejie Formation in China is poor with fast formation pressure drop, rapid production decline and numerous abnormal wells due to the influence of low permeability, strong heterogeneity, ultra-high reservoir temperature and pressure and high wax and asphaltene content. To overcome these difficulties, this paper takes geological conditions, reservoir potential, stimulation technology and actual wells situation into consideration on the basis of the reservoir performance research, and gives full play to the integration of reservoir and mechanical recovery. A set of production enhancement and efficiency improvement technologies has been formed, including moderate periodic water injection based on pressure fluctuation theory, liquid extraction optimization for low permeability fields, modified compound plugging removal technology, small flowrate and broad width electric pump selection technology, and pump stuck early warning technique to achieve the efficient development of offshore low-permeability oilfields. Moderate periodic water injection not only makes full use of the imbibition effect to achieve the equilibrium displacement, but also avoids the water channeling in fracture area; eight main controlling factors are used to classify and evaluate the liquid extraction potential and select the well group at level-1 for the workover with the effect of daily oil increase of 42 m3; modified compound plugging removal technique completely removes the pollution and plugging of the formation and the wellbore to release the potential of the oil wells to the greatest extent and cumulative oil increase of 6 well times is expected to be 12.44×104 m3; small flowrate and broad width electric pump selection technology applied for more than 30 well times improves the adaptability of the pumps substantially and extends the pump inspection cycle to 857 days; real-time pump stuck warning technique through the dual pattern of analyzing both conventional and high-frequency data guarantees the efficient operation of oil wells. The technologies in this paper have been applied in the target low-permeability field with daily oil production of 429 m3, oil recovery rate of 1.1%, natural decline rate drop year by year and the expected recovery factor of 20.9% under current well pattern. The key technologies in this paper have improved the target reservoir development effect significantly and provided important reference significance for other offshore low-permeability reservoirs development.

Device for modeling of intra-arterial circulation: application in experimental cardiology

Purpose of study Using an original device for modeling of intra-arterial blood circulation, to study the features of intravascular hemodynamics with a regular heart rhythm and with various rhythm disturbances. Material and methods We used an original device developed by us to simulate intra-arterial circulation (Document of invention No. RU 202780 U1). The main part of the device is a glass tube of a rotameter with a length of 365 mm, an inlet end with a diameter of 20 mm, an outlet end of 16.5 mm, which is a model of an arterial vessel. Flexible silicone tubes are attached to the rotameter on both sides, with free ends connected to an electric pump, with various modes of operation (imitation of pulse waves with regular rhythm, premature ventricular contractions (PVCs), atrial fibrillation (AF). An aqueous solution of glycerin was introduced into a closed system diluted with water corresponding to the viscosity of the blood. A 5 mm long silk thread was alternately installed inside the tube, an intravascular piezoelectric crystal pressure probe connected to an oscilloscope. Also it was injected inside the tube a dye - clerical ink. Results With electric pump, we simulated the spreading of the pulse wave in regular heart rate, PVCs and AF. We observed the effect of a pressure wave (deflection of a silk thread, the appearance of a turbulent flow when using a dye) on the walls of the rotameter, with the formation of standing, reflected waves during the PVCs and AF. The pressure probe registered an increase in pressure inside the tube during the spread of the 1st post-extrasystolic contraction wave up to 58%, the wave after a long pause of more than 2 seconds with AF by 44% compared to the regular rhythm. Conclusion A device for modeling of intra-arterial circulation allows a wide range of experimental work in cardiology, normal and pathological physiology, and biophysics. FUNDunding Acknowledgement Type of funding sources: None.