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The purpose of this study is to investigate the performance of fire protective materials in protecting steel section. A new indexing system is introduced, named as fire endurance index (FEI), which can be used to evaluate the performance of fire protective materials.

In this study, experiments were carried out using W4 × 13 steel section. Eight samples were prepared; one was a bare steel section without any coating material, and seven were prepared using four types of materials such as vermiculite-gypsum plaster, gypsum plaster, concrete cover and glass wool-concrete cover for fireproofing of the sections. An enclosed electric coiled furnace was used for heating the samples for a certain period. The duration of protection was determined, and the FEI of the materials was calculated. The higher the index value is, the better the performance.

The results demonstrate that the glass-wool-concrete cover offered the best performance at high temperature among the four types of materials. In the experiment with glass-wool-concrete cover, the furnace temperature reached 750°C, whereas the steel temperature reached only 100°C. The FEI of the coatings were calculated. Among the eight samples, glass wool-concrete cover also achieved the highest index value.

The experimental work was performed using a limited number of specimens. Furthermore, the robustness of the indexing system needs to be evaluated with other materials and a wide range of heating rate and temperature. This study sets the foundation for future work.

The findings of this research may contribute to a better understanding of the performance of the materials used as fire protective coatings. This might be helpful for the researchers and practitioners in their design and implementation of legislation of fire safety codes.

Understanding the performance of the fire protective coatings will help in evaluating the fire resistance capabilities of the materials to use for the structural steel members, which may protect collapses and disasters of buildings.

This paper deals with the performance of four types of materials, that can be used as fire protective coatings for structural steel members. Furthermore, the FEI explicitly indicated their performance with numerical values. In this study, the heating of the specimens was performed using a non-standard fire curve based on the concept that naturally occurring incidents of fire do not follow the standard fire curves.

The objective of this work was to develop practical experimental techniques for monitoring corrosion in “difficult‐to‐test” conditions such as corrosion under insulation (CUI).

An electrochemically integrated multi‐electrode array namely the wire beam electrode (WBE) method has been used in combination with noise signature analysis for the first time to monitor the penetration of corrosive species under simulated corrosion‐under‐insulation conditions. Corrosion of aluminium exposed under insulation materials such as rock wool, glass wool, cotton wool and tissue paper has been successfully monitored.

A typical potential noise signature of a major potential jump from AA1100 WBE was observed which corresponded to the corrosive species reaching the WBE surface in WBE current distribution map. A good correlation between the galvanic current maps and the corroded surface was also observed.

The preliminary results suggest that the proposed novel electrochemical method is capable of monitoring CUI.

Refractance window drying (RWD) has been identified as the method that can give high-quality products at a relatively low production cost. However, knowledge about its use and adoption remains lacking both in academic curricula and industry in the developing world.

A lab-scale batch RWD of a closed-loop control system was designed, fabricated and evaluated for drying rates, evaporation rate, the energy of evaporation, energy efficiency and throughput. Testing was done using mango and tomato pulps.

Drying rates at 95°C of 1.32 gg⁻¹min⁻¹ and 0.854 gg⁻¹min⁻¹ at 2 and 3 mm, respectively, for tomato, 0.6 gg⁻¹min⁻¹ and 0.33 gg⁻¹min⁻¹ at 2 and 3 mm for mango pulp were obtained. The dryer had an evaporation rate of 4.63 × 10^–4 kg/s and 4.25 × 10^–4 kg/s, the energy of evaporation of 1.05 kW and 0.96 kW and thermal energy efficiency of 25.64% and 21.73% while drying tomato and mango pulps, respectively. Dryer throughput of 0.6 kg/h of dried mango Pulp and 0.47 kg/h of dried tomato pulp was obtained.

The designed RWD can be adequately used in laboratory experiments on different products to produce powders. This will enable the transfer of knowledge about RWD technology in developing countries.

This paper aims to present a comparative study of a solar dryer with and without multiple phase change materials (PCMs). It also involves designing and fabricating the experimental model of an indirect solar dryer which uses PCMs for thermal energy storage.

A corrugated aluminium sheet is used as an absorber plate. Aluminium pipes of 0.75 inch are welded under the corrugated sheet to store the PCM. Here, multiple PCMs are used – one with a high melting point and the other with a low melting point for the purpose of improving efficiency. A single air pass model in which air moves over the absorber plate is used for the study. Air is heated in an air heater section which also contains thermal energy storage. The energy obtained in the air heater section is first used to heat and melt the PCM.

Thus, heat energy is stored into the PCM and then the heated air moves into the drying chamber in which drying take place. When the sun’s insolation reduces, discharging from the PCM takes place. Thus, it reduces the fluctuation in the energy and provides continuous energy to the system. Glass wool is used as an insulation material. Different parameters for this air heater-dryer have been calculated.

The current study enhances the understanding of solar drying process and the developed model with and without multiple phase change materials can be used for optimising the drying process.

The examination and identification of solvents and binder resins in particular has been discussed in detail previously. It is the sole purpose of this section to indicate the means available for obtaining these substances from finished paints in such a way as to facilitate their analysis. For example, the ASTM (15) has published a standard procedure for examining the solvent portion of paints by direct injection on to a GC. In this case, so as to prevent blockage of the column by the resin and pigment components, the sample was injected either via a glass injection port sleeve or on to a glass wool plug positioned in the heated injection port. Hence solvent analysis could be carried out without the need to apply any preliminary separation procedures. If however, both solvent and binder resin are to be examined then a procedure for separating these constituents must be applied.

This work aims to present an experimental study of steel fibre-reinforced concrete (SFRC) subjected to high temperature, especially focusing on residual behaviour.

Compressive strength and split tensile strength of SFRC cubes and ultimate bending strength of prisms were evaluated under ambient and elevated temperatures. The specimens were heated by ceramic heaters and then repacked for testing.

The results showed that a compressive strength of SFRC is reduced by 38 and 66 per cent, tensile strength is reduced by 25 and 59 per cent and ultimate bending force is reduced by 33 and 56 per cent in case of 400°C and 600°C, respectively, comparing with ambient temperature.

The developed testing procedure could be used for determination of material properties of SFRC under elevated temperatures.

A general numerical method for finding the steady state solution of a cyclic system is presented. The method determines the initial values by enforcing the conditions of periodicity. In this way the initial value is found by integrating through only one cycle, often resulting in a considerable saving of computing effort. The method is applicable to any linear discrete set of difference equations with periodic parameters and forcing functions. The application of the method to a single pole representation of heat flow in buildings is demonstrated.

ENGINE starting at low temperatures is difficult for the following reasons: (a) A cold engine requires higher torque to start it and thus imposes a greater load on the accumulator. This is not so marked with ball or roller bearings.

IN order to make available to industry generally the means for testing materials and products under various climatic conditions, particularly in tropical conditions conducive to corrosion, the Dutch research organisation Centrale Organisatie voor Toegepast Natuurwetenschappelijk Onderzoek (T.N.O.)—Central Organisation for Applied Physical Research—has recently founded an institute at Rijswijk (Z.H.), near Delft, known as Klimaat‐kamers T.N.O., which incorporates test chambers for simulating climatic conditions to be found in various parts of the world. Should sufficient interest be forthcoming from industry it is further proposed to enlarge the institute to include other facilities such as test installations for observing the effect of salt spray, dust storms and low temperatures.

The most efficient method of lubricating the cylinders of steam engines is to employ an atomizer in the steam flow, situated a little distance before it enters the steam cylinders, and thus inject the oil in the form of a spray so that the steam carries it to the cylinder walls and valves. In other words, the steam is made to act as a lubricant. In this way there should be no part that comes into contact with oil that is unlubricated and, furthermore, this is not only the most efficient method of lubricating a steam engine, it is also the most economical, since only small quantities are required of the finely atomized oil. It is possible to lubricate a number of pumps or several high and low pressure steam cylinders from a single feed lubricator in this way.