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Paint drying is a very important process in an industry where shorter drying time for productivity and lower energy consumption for production cost are required while maintaining the product’s painting quality. In the present study, a drying process in a line-type paint drying furnace equipped with nozzles for hot air supply and moving conveyer belt to dry painted automotive parts is numerically simulated for the flow and heat transfer inside the furnace to evaluate the quality of the drying or baking at the end of the drying process in a production line.

A baking window for a specific paint is used for judging the local degree of baking (DOB) of the painted parts, which can be useful to identify under-baked or over-baked locations of the painted parts, and hence the quality of the baking process.

Numerical results of a time history of temperatures at two monitoring points on the painted parts were obtained and compared to the measured data in an actual furnace and showed good agreement. Three types of paints were considered in the present study and numerical results showed different drying characteristics. In addition to the original furnace nozzle configuration, two more furnace nozzle configurations with different numbers, direction and speed of hot air supply were simulated to improve the furnace’s drying performance. As a result, a newly suggested nozzle configuration with quick drying paint can give us a remarkable improvement in surface averaged DOB compared to the original nozzle configuration with original paint.

The present simulation technique and DOB methodology can be used for the optimal design of a drying furnace.

This study aims to present a numerical analysis of the behavior of the electric field and flow field characteristics under electrohydrodynamics (EHD) force. The influence of the jet airflow under the EHD force is investigated when it impacts the inclined flat plate.

The high electrical voltage and angle of an inclined flat plate are tested in a range of 0–30 kV and 0–90^°, respectively. In this condition, the air is set in a porous medium and the inlet jet airflow is varied from 0–2 m/s.

The results of this study show that the electric field line patterns increase with increasing the electrical voltage and it affects the electric force increasing. The angle of inclined flat plate and the boundary of the computational model are influenced by the electric field line patterns and electrical voltage surface. The electric field pattern is the difference in the fluid flow pattern. The fluid flow is more expanded and more concentrated with increasing the angle of an inclined flat plate, the electrical voltage and the inlet jet airflow. The velocity field ratio is increased with increasing the electrical voltage but it is decreased with increasing the angle of the inclined flat plate and the inlet jet airflow.

The maximum Reynolds number, the maximum velocity field and the maximum cell Reynolds number are increased with increasing the electrical voltage, the inlet jet airflow and the angle of the inclined flat plate. In addition, the cell Reynolds number characteristics are more concentrated and more expanded with increasing the electrical voltage. The pattern of numerical results from the cell Reynolds number characteristics is similar to the pattern of the fluid flow characteristics. Finally, a similar trend of the maximum velocity field has appeared for experimental and numerical results so both techniques are in good agreement.

Steel structures have often been painted with good, unbroken films which have lasted as long as ten years without repainting, in reasonably dry and unpolluted areas. To endeavour to reach such an ideal state on the steel structures and plants which are essential features of a large integrated steelworks is a much more costly and difficult process. It must be appreciated that much of the plant engaged in or ancillary to the production of iron and steel operates continuously with very few shutdown periods for maintenance. This is particularly true of the coke‐oven and by‐products plants and unfortunately much of the corrosion at steelworks is due to the operating conditions which are necessary for the continuous production of coke. In this article the maintenance painting of steelworks in similar conditions is described.

In any environment careful consideration must be given to the most cost effective way to protect steel and concrete structures against the effects of corrosion. The special factors which apply to sewage and water treatment plants are described and examples are given of systems which have been used for their protection throughout the world. Paint is the material most widely used to protect steel. Surface preparation, selection of the paint resin, total dry film thickness, ease of application and maintenance are among the many factors to be considered when deciding which type of paint system to use. Where concrete is painted, the need for an alkali resistant paint is an additional factor to be considered.

Making Fine Powders ‐ Extremely fine and uniform particles, of 5–50 nanometers, have been produced by a process being developed at Battelle Pacific Northwest Laboratories. Researchers have used the technique to synthesize new, highly dispersed catalysts with a high surface area. It offers a way to make other products which have improved properties: ceramic ball bearings and gears which are stronger and more durable than those available today, and pigments for paints and inks.

A mixed metal oxide-based spinel ceramic pigment has been successfully synthesized incorporating inorganic, high-temperature stable furnace cement as an inbuilt binder. Step by step synthesis was done for the spinel and cement mix formulations.

The pigment mix was synthesized by a solid-solid method where the inorganic binder was incorporated in the mix. The results suggested that CoCuMn-based spinel ceramic pigment with cement mix could be obtained at an annealing temperature of 1,100ºC for 1 h and the size, morphology and crystallinity of spinel mix were greatly influenced by the calcination temperature.

The pigment mix synthesized was applied as a coating to different substrates such as aluminum, glass and Mild steel. The results revealed that spectral selectivity of TSSS paint coatings based on the CoMnCu spinel ceramic mix was much better than that of solvent-based coatings for high-temperature applications. The presence of cement as an inorganic binder makes the functioning and application of paint easy as it becomes that of a waterborne type.

Ease of application, stability at high temperatures, best absorptivity at the solar selective spectrum and excellent adhesion properties for the selected surface are the key features of the designed pigment system. The applied pigment mix was studied as a coating to get the results for solar selective system.

Melting Furnaces. A British firm has recently developed mains frequency ferrous and non‐ferrous electric melting furnaces. These are specially designed for large and small furnaces.

CORROSION is a continual problem for those who are responsible for metal structures and the well‐known Southend Pier provides Mr. Frank Flintoff, the pier manager, and his staff with a never‐ending task of protecting the mile‐and‐a‐third‐long steel framework against exposure to a heavily salt‐laden atmosphere. The pier is situated on the Essex side of the Thames Estuary and the scheme of protection devised for the Southend Pier has to take into consideration also the pitting and chemical effect of minute cement particles which are carried towards the pier by the prevailing south‐west wind from a factory six miles away on the other side of the estuary.

Widespread use is being made of Meehanite metal castings, which are produced in a number of different types, each processed to give a particular set of physical properties and to meet a specific need. They are broadly divided into four groups: general engineering, heat, wear and corrosion resistance. Each group consists of several types, all made to definite specifications.

The spectrally selective solar absorption paint is prepared from spinel-based mixed metal oxides with inorganic binder as a key component. Inorganic binder (furnace cement) is blended with mixed metal oxide pigment during synthesis. High temperature stability upto 1,100ºC is achieved by the use of this modified coating system. The purpose of this paper is to work on solar selective coating synthesis, and application of a coating as a water-borne paint is the additive key feature that helps in reduction of solvent use.

The paint was formulated using water-based system, and the main component of colorant was made by mixed metal oxide–based spinel pigment and highly temperature stable inorganic binder.

The paint formed shows excellent absorptive power with low emittance even at high temperature. Optical and thermal properties were determined along with adhesion, abrasion and other properties. The solar absorptance for these samples were as = 0.93–0.95 with corresponding thermal emittance of eT = 0.096 (at room temperature) and 0.2–0.22 (at elevated temperature 100°C).

The paint formed shows excellent absorptive power with low emittance even at high temperature. The paint can be applied in solar absorptive tower system. The obtained results indicated excellent thermal stability of prepared paint coatings. As inorganic binder was used, the paint has reduction in solvent use, and being water as a base, it is environment friendly, easy to apply and durable at high temperatures, as the binder itself is stable up to 1,500ºC.