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This paper aims to present a different cooling method (water cooling) to protect all the mechanical/electrical components for Tokamak in-vessel inspection manipulator. The method is demonstrated effective through high temperature experiment, which provides an economical and robust approach for manipulators to work normally under high temperature.

The design of cooling system uses spiral copper tube structure, which is versatile for all types of key components of manipulator, including motors, encoders, drives and vision systems. Besides, temperature sensors are set at different positions of the manipulator to display temperature data to construct a close-loop feedback control system with cooling components.

The cooling system for the whole inspection manipulator working under high temperature is effective. Using insulation material such as rubber foam as component coating can significantly reduce the environmental heat transferred to cooling system.

Compared with nitrogen gas cooling applied in robotic protection design, although it is of less interest in prior research, water cooling method proves to be effective and economical through our high temperature experiment. This paper also presents an energetic analysis method to probe into the global process of water cooling and to evaluate the cooling system.

The purpose of this paper is to experimentally and numerically investigate the cooling performance of the air-to-water thermoelectric cooling system under different working conditions.

An air-to-water thermoelectric cooling system was designed and manufactured according to the principle of discrete binary thermoelectric Peltier modules, and the thermal performance, heat transfer rate and average COP values were examined at different cooling water temperatures and voltages applied. Additionally, numerical simulations were performed by computational fluid dynamics approach to investigate the temperature distribution and airflow structure inside the cooling chamber.

Analyses were performed using experimental tests and numerical methods. It was concluded that, by decreasing the cooling water temperature from 20 to 5 °C, the average COP increases about 36%. The voltage analysis showed that the efficiency of the system does not always increase as the voltage rises; more importantly, the optimum voltage is different and depends on whether it is desired to increase COP or increase the cooling rate.

In the studies published in the field of thermoelectric cooling systems, little attention has been paid to the voltage applied and its relationship to other operating conditions. In most cases, the tests are performed at a constant voltage. In this study, several options, including applied voltage and cooling water temperature, were considered simultaneously and their effects on performance have been tested. It was found that under such studies, optimization work should be done to evaluate maximum performance in different working conditions.

The hollow copper wires of the generator are seriously corroded in cooling water. This paper aims to explore the mechanism of copper corrosion by thermodynamic calculation and kinetic experiments and to find out the precise pH range for preventing corrosion of copper in stator internal water and dual internal water cooled generators.

Thermodynamic and kinetic studies were carried out for the purpose of preventing the corrosion of hollow conducting copper wires in the internal cooling water. Thermodynamic calculation results demonstrate hollow copper wires electrochemically corroded by oxygen rather than acids (H+) and find out a precise anti-corrosion pH range. Kinetic experiments research on the effect of the pH value and oxygen concentration on corrosion and protection methods of copper in desalted water.

Research results demonstrate that, in the internal cooling water, hollow copper wires are electrochemically corroded by oxygen, rather than acids (H+). The method of preventing copper from corrosion in the desalted water is to control the pH value of the stator cooling water and the dual water inner cooling water between 7.86-8.86 and 7.86-9.26, respectively.

The thermodynamic calculation and potentiometric-pH diagram are used to obtain the accurate pH range of the inner cooling water and inner cooling water in the inner cooling water system. The kinetic experiments provide data support for the effect of temperature, pH value and oxygen concentration.

The buried pipe element method can be used to calculate the temperature of mass concrete through highly efficient computing. However, in this method, temperatures along cooling pipes and the convection coefficient of the cooling pipe boundary should be improved to achieve higher accuracy. Thus, there is a need to propose a method for improvement.

According to the principle of heat balance and the temperature gradient characteristics of concrete around cooling pipes, a method to calculate the water temperature along cooling pipes using the buried pipe element method is proposed in this study. By comparing the results of a discrete algorithm and the buried pipe element method, it was discovered that the convection coefficient of the cooling pipe boundary for the buried pipe element method is only related to the thermal conductivity of concrete; therefore, it can be calculated by inverse analysis.

The results show that the buried pipe element method can achieve the same accuracy as the discrete method and simulate the temperature field of mass concrete with cooling pipes efficiently and accurately.

This new method can improve the calculation accuracy of the embedded element method and make the calculation results more reasonable and reliable.

This article discusses the basics of computer‐room air conditioning, an important component of the special environment required by mainframe computers and many mini‐computers as well. Computer room air conditioners differ in some significant ways from “comfort” air‐conditioners, which are designed for the comfort of people rather than machines. These differences make it less than ideal to use air conditioning systems designed for human comfort for computer cooling. The author describes several different types of air‐conditioners, considerations related to the construction of a computer room, and factors that determine air‐conditioning requirements.

An effective chemical conditioning technique was successfully tested and investigated to control and minimize the chemistry-related damages within mixed metallurgy steam and water cycle of Heller dry cooled combined cycle power plants (CCPPs), in which cooling water and condensate are completely mixed in direct contact condenser. This study aims to perform a comprehensive experimental research in four mixed metallurgy steam and water cycle.

A comprehensive experimental study was carried out in four mixed metallurgy steam and water cycle fabricated with ferrous- and aluminum-based alloys which have various corrosion resistance capabilities in contact with water. Chemical conditioning was conducted using both volatile and non-volatile alkalizing agents, and, to perform chemical conditioning effectively, quality parameters (pH, conductivity, dissolved oxygen, sodium, silica, iron, aluminum and phosphate) were monitored by analyzing grab and online samples taken at eight key sampling points.

Results indicated that pH was the most critical parameter which was not mainly within the recommended ranges of widely used standards and guidelines at all key sampling points that generally increases the occurrence of chemistry-related damages. The other quality parameters were mostly satisfactory.

In this research, the development of a suitable chemical conditioning technique in mixed metallurgy steam and water cycle, fabricated with ferrous and aluminum-based alloys, was studied. The obtained results in this thorough research work was evaluated by comparison with the chemistry limits of the widely used standards and guidelines, and combined use of volatile and solid alkalizing agents was considered as a promising chemical conditioning technique for utilization in mixed metallurgy units of Heller dry cooled CCPPs.

Pipe cooling is an important measure for controlling the temperature in mass concrete. Since the temperature field in mass concrete containing cooling pipes is unsteady and three‐dimensional, and there are huge quantities of the cooling pipes in the concrete, the study of efficient and reliable algorithm is crucial. The purpose of this paper is to develop the composite element method (CEM) for the temperature field in mass concrete containing cooling pipes.

Each cooling pipe segment is looked at as a special sub‐element having definite thermal characteristics, which is located explicitly within the composite element. By the variational principle, the governing equation for the composite element containing cooling pipes is established.

One of the remarkable advantages of the method proposed is that each cooling pipe can be simulated explicitly while the difficulty of mesh generation around cooling pipes can be avoided.

The paper demonstrates how composite elements containing cooling pipes are degenerated to the conventional finite elements automatically when the first stage artificial cooling finished, and conversely, the conventional finite elements can also be transformed to the composite elements automatically when the second stage artificial cooling started. The comparison of the numerical example using FEM and CEM shows the rationality of the proposed method.

The aim of this study is to analyze future changes of freshwater needs in the electricity production sector and to identify hotspots where future cooling water needs may not be fulfilled.

To address the goals of this study, a scenario and simulation approach was selected to estimate water availability and water uses in Europe up to 2050. Two SCENES scenarios were selected to cover a wide range of water‐related driving forces including future developments in population, GDP, electricity production, technological and structural changes, as well as climate change.

Depending on the scenario, water withdrawals in the electricity production would increase by 68 percent or decrease by 33 percent between 2000 and 2050. At the same time, water availability at low flow (Q90) would decrease because of climate change in southern and south‐eastern parts of Europe as well as in Ireland and the UK. Especially in these regions hotspots were identified where water is scarce and where growing water demand promotes water stress that may cause economic losses.

This paper presents hotspots of the thermal electricity production sector in Europe. In these regions water shortages were expected to lead to water stress due to climate change accompanied by increasing water demand for cooling purposes and by competing water use sectors.

The aim was to study the effect of an electromagnetic treatment used on corrosion control of carbon steel in cooling systems.

The aim was to assess the performance of an electromagnetic treatment used on corrosion control of carbon steel in cooling water systems.

The main conclusion is that the electromagnetic system cannot induce a direct effect on the corrosion rates. The use of chemical corrosion inhibitors cannot be suggested.

The optimized industrial use of water is an objective of unquestionable importance, as water is a finite resource. The use of efficient corrosion control on water cooling systems permits the reduction of the water volume required. Consequently, a social benefit can be associated with the improvement of corrosion control technologies.

The development of alternative corrosion control technologies, such as the use of physical treatments, has been considered as a promising tool. In this work, a consistent assessment of the results achieved on a full-scale system, without using chemical corrosion inhibitors, is presented.

Cold-formed steel (CFS) sections are a popular choice for constructing medium and low-rise structures that are engineered to support relatively light loads. An important characteristic of CFS sections is that they are produced without the use of heat during manufacturing. Consequently, it becomes essential to gain a comprehensive understanding in the behavior of CFS sections when exposed to fire or elevated temperatures.

In this study, sections of 1.5 m length and 2 mm thickness were taken and analyzed to find its flexural behavior after heating them for 60 and 90 min. There were two modes of cooling phase which was considered to reach ambient temperature, i.e. air or water respectively. Performance of each sections (C, C with inclined flanges, sigma and Zed) were examined and evaluated at different conditions. Effects of different profiles and lips in the profiles on flexural behavior of CFS sections were investigated fully analytically.

The variation in stiffness among the sections with different lipped profiles was noted between 20.36 and 33.26%, for 60 min water cooling case. For the sections with unlipped profiles, it was between 23.56 and 28.60%. Influence of lip and section profile on reduction in stiffness is marginal. The average reduction in load capacity of sections for 60 min specimens cooled by water was found to be 43.42%. An increase in deflection is observed for the sections in the range of 25–37.23% for 60 min case. This is the critical temperature responsible for reduction in yield strength of material as it substantially increases the material safety margin to be considered for the design. Sections with Zed profile have shown better performance among other types, in terms of its load carrying capacity.

This paper deals with the flexural behavior of Galvanized (GI) based CFS unsymmetric sections at elevated temperature and cooled down to ambient temperature with air or water.