Stability conditions for a heat transfer object control system with Schipanov controller under imperfections in the controller

2016 ◽  
Vol 77 (12) ◽  
pp. 2159-2174
Author(s):  
E. M. Solnechnyi
2021 ◽  
pp. 36-51
Author(s):  
Рустем Юсуфович Турна ◽  
Артем Михайлович Годунов

The progress of space technology is leading to more and more energy-equipped spacecraft. The International Space Station already has the capacity of solar panels of more than 100 kW. Autonomous spacecrafts and satellites (including stationary ones) have the capacity of power units of kW, in the nearest future - more than 10 kW. Forced heat transfer using single-phase liquid coolants is still considered as the main method of thermal control on high-power spacecraft (SC). Single-phase mechanically pumped fluid loop is a fully proven means of thermal control of spacecraft with a moderate heat load. A significant disadvantage of such systems is that the coolant temperature varies significantly within the loop. The temperature difference can be reduced by increasing the coolant flow rate, but for this, it is necessary to increase the pump capacity, which inevitably leads to an increase in power consumption, pipeline diameters, and weight of the system as a whole. In the case of spacecraft with high power capacity (more than 5-10 kW) and large heat transfer distances (10 m and more), a two-phase mechanically pumped fluid loop for thermal control is more preferable in terms of weight, the accuracy of thermoregulation, power consumption (and other parameters). The use of a two-phase loop (2PMPL) as a spacecraft thermal control system allows to reduce significantly mass and power consumption for own needs in comparison with a single-phase thermal control system (TCS). The effect is achieved due to the accumulation of transferred heat in the form of latent heat of vaporization and intensification of heat exchange at boiling and condensation of coolant. The article provides a critical review of published works on 2PMPL for spacecraft with high power (more than 5...10 kW) and a large heat transfer distance (more than 10...100 meters) from 1980 up to nowadays. As a result, a list of the main problems on the way of practical implementation of two-phase loops is formed.


2018 ◽  
Vol 769 ◽  
pp. 371-376 ◽  
Author(s):  
Elena Alexandrovna Muravyova ◽  
Alexander Ivanovich Kubryak

The article describes the development of a mathematical model for a condenser-evaporator, which occupies a central position in chlorine liquefaction process. The model describes the key processes in the equipment unit: freon evaporation, chlorine condensation, change in freon level and in equipment pressure. The model is based on the equations characterizing the processes mentioned above, which makes it possible to use the model for design and calculations of non-contact heat transfer equipment with phase transitions of heat carriers of various characteristics. The simulation was carried out with the aim of further development of a condenser-evaporator control system.


2019 ◽  
Vol 256 ◽  
pp. 03002
Author(s):  
Han Xiao ◽  
Zhou Ying ◽  
Jia Ruijin ◽  
Zijuan Wang

The optical characteristics of the space science detectors are very sensitive to the temperature fluctuation. In order to study the effect of it, a method to simulate the temperature fluctuation was put forward in this paper, and the feasibility of this method was verified numerically. A radiation disturbance was artificially applied at a certain distance from the test platform, so that the surface temperature of the platform changed periodically with the radiation heater. The results show that the radiation heat transfer disturbance could produce a temperature fluctuation on the test platform, which provides a reliable theoretical support for the time-varying temperature control system.


1966 ◽  
Vol 88 (2) ◽  
pp. 337-342 ◽  
Author(s):  
H. C. Khatri ◽  
R. E. Goodson

In the design of controllers for heat transfer systems, one must often describe the plant dynamics by partial differential equations. The problem of optimizing a controller for a system described by partial differential equations is considered here using exact and approximate methods. Results equivalent to the Euler-Lagrange equations are derived for the minimization of an index of performance with integral equation constraints. These integral equation constraints represent the solution of the partial differential equations and the associated boundary conditions. The optimization of the control system using a product expansion as an approximation to the transcendental transfer function of the system is also considered. The results using the two methods are in good agreement. Two examples are given illustrating the application of both the exact and approximate methods. The approximate method requires less computation.


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