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The purpose of this study is to examine the effects of inclination angle on the thermal energy storage capability of a phase change material (PCM) within a disc-shaped container. Different container materials are also tested such as plexiglass and aluminium. This study aims to assess the energy storage capacity, melting behaviour and temperature distributions of PCM with a specific melting range (22°C–26°C) for various governing parameters such as inclination angles, aspect ratios (AR) and temperature differences (ΔT) and compare the melting behaviour and energy storage performance of PCM in aluminium containers to those in plexiglass containers.

A finite volume approach was adopted to evaluate the thermal energy storage capability of PCMs. Five inclination angles ranging from 0° to 180° were considered and the energy storage capacity. Also, the melting behaviour of the PCM and temperature distributions of the container with different materials were tested. Two different AR and ΔT values were chosen as parameters to analyse for their effects on the melting performance of the PCM. Conjugate heat transfer problem is solved to see the effects of conduction mode of heat transfer.

The results of the study indicate that as AR decreases, the effect of the inclination angles on the energy storage capacity of the PCM decreases. For lower ΔT, the difference between the maximum and minimum stored energies was 20.88% for AR = 0.20, whereas it was 6.85% for AR = 0.15. Furthermore, under the same conditions, the PCM stored 8.02% more energy in plexiglass containers than in aluminium containers.

This study contributes to the understanding of the influence of inclination angle, container material, AR and ΔT on the thermal energy storage capabilities of PCM in a novel designed container. The findings highlight the importance of AR in mitigating the effect of the inclination angle on energy storage capacity. Additionally, comparing aluminium and plexiglass containers provides insights into the effect of container material on the melting behaviour and energy storage properties of PCM.

This study aims to focus on understanding how different jet angles and Reynolds numbers influence the phase change materials’ (PCMs) melting process and their capacity to store energy. This approach is intended to offer novel insights into enhancing thermal energy storage systems, particularly for applications where heat transfer efficiency and energy storage are critical.

The research involved an experimental and numerical analysis of PCM with a melting temperature range of 22 °C–26°C under various conditions. Three different jet angles (45°, 90° and 135°) and two container angles (45° and 90°) were tested. Additionally, two different Reynolds numbers (2,235 and 4,470) were used to explore the effects of jet outlet velocities on PCM melting behaviour. The study used a circular container and analysed the melting process using the hot air inclined jet impingement (HAIJI) method.

The obtained results showed that the average temperature for the last time step at Ф = 90° and Re = 4,470 is 6.26% higher for Ф = 135° and 14.23% higher for Ф = 90° compared with the 45° jet angle. It is also observed that the jet angle, especially for Ф = 90°, is a much more important factor in energy storage than the Reynolds number. In other words, the jet angle can be used as a passive control parameter for energy storage.

This study offers a novel perspective on the effective storage of waste heat transferred with air, such as exhaust gases. It provides valuable insights into the role of jet inclination angles and Reynolds numbers in optimizing the melting and energy storage performance of PCMs, which can be crucial for enhancing the efficiency of thermal energy storage systems.

This study aims to investigate the effect of the material thickness and build orientation on the mass transfer of low molecular weight substances through polyamide 12 (PA12) structures produced by laser sintering (LS).

Disc-shaped PA12 sheets having a nominal thickness ranging from 700 to 2,000 µm were built in horizontal, vertical and diagonal orientations and their permeation properties to oxygen and water vapor were measured. The structural properties of the sheets were examined by X-ray micro-computed tomography, differential scanning calorimetry and polarized light microscopy.

All the LS sheets that were investigated had water vapor and oxygen permeation coefficients that are in the range of those of PA12 produced by traditional manufacturing technologies. Despite significant differences in the porosity characteristics, the permeation properties of sheets built in different orientations were similar. The pores seem to have no measurable effect on the mass transfer rates in the sheets, and the transport processes seem to predominantly follow the rules of a regular solution-diffusion mechanism. The results showed a non-significant trend toward thickness-dependent permeation coefficients, which agrees with the observed differences in the crystal structures of the sheets.

The results are an important basis for the qualification of LS technology for direct manufacturing in applications requiring special barrier performance.

This study provides new information on mechanisms of mass transport through LS PA12 and the effect of the material thickness and build orientation. Furthermore, the results enhance understanding of the structural properties of thin polymeric sheets produced by LS.

BA Chemicals Ltd., Chalfont Park, Gerrards Cross, Bucks. SL9 0QB, are now able to offer fine grades of alumina and alumina hydroxide powders which will be of interest to coatings manufacturers.

This study aims to develop and evaluate an inexpensive and durable metal cutting wheel using thermal spraying and polymer binding to enhance the wheel’s cutting capability by bonding hard particles (abrasives) onto the wheel.

Thermal spraying was used to deposit the coating powder (chromium and silicon carbide) onto high carbon substrate. Wear loss and depth of cut as function of load, time and speed were evaluated on uncoated and coated wheel.

The coated cutting wheel performed better than the uncoated cutting wheel in terms of wear performance. However, the coated cutting wheel experienced coating peel off at higher load and cutting speed, leading to a decrease in wear resistance of the cutting wheel. Thus, optimally cutting should be performed either at low cutting speed and high load or at high cutting speed and low load to prolong the wheel’s lifetime.

The outcome of the study will be beneficial for academicians and industrial working on cutting wheel process.

Examines the tenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

IN recent years there has been a revival of interest in aerostatic aircraft. The natural advantages of “displacement type” flying machines have been often repeated but particular emphasis has been made on economy and safety. The prime reason is that power is required for propulstion and control and not for aerodynamic lift.

Laser sintering kinetics and part reliability are critically dependent on the melt viscosity of materials, including polyamide 12 (PA‐12). The purpose of this paper is to characterise the viscosity of PA‐12 powders using alternative scientific methods: constrained boundary flows (capillary rheometry) and rotational rheometry.

Various PA‐12 powders were selected and characterised by both techniques. Measurement of molecular weight was also carried out to interpret the viscosity data.

Results demonstrate conventional pseudoplastic flow in all PA‐12 materials. Zero‐shear viscosity has been quantified by rotational rheometry; a notable observation is the striking difference between virgin/used PA‐12. This is interpreted in terms of molecular weight and chain structure modifications, arising from polycondensation of PA‐12 held at the bed temperature during laser sintering.

Accurate zero‐shear viscosity data provide scope for use in predictive computational models for laser sintering processes. Careful sample preparation and equipment operation are critical prerequisites for accurate rheological characterisation of PA‐12 powders.

Differences in flow behaviour and molecular structure allow prediction and deeper understanding of process‐property relationships in laser sintering, giving potential for further optimisation of material specification and in‐process machine parameter control.

This is believed to be the first time that techniques other than melt flow rate (MFR) have been reported to measure the viscosity of PA‐12 in a laser sintering context, noting the effects of pre‐drying and molecular weight, then predicting differences between virgin/used powders in practical sintering behaviour.

FOR some time industry has been preoccupied with the question of management. It is generally agreed that in the United States the services of management consultants are engaged by at least 75 % of the principal industrial enterprises, hospitals and chief educational establishments. In this country, too, there is growing reliance on the same kind of aid.

This paper presents a new indirect scaffold fabrication method for soft tissue based on rapid prototyping (RP) technique and preliminary characterization for collagen scaffolds.

This paper introduces the processing steps for indirect scaffold fabrication based on the inkjet printing technology. The scaffold morphology was characterized by scanning electron microscopy. The designs of the scaffolds are presented and discussed.

Theoretical studies on the inkjet printing process are presented. Previous research showed that the availability of biomaterial that can be processed on a commercial RP system is very limited. This is due mainly to the unfavorable machine processing parameters such as high working temperature and restrictions on the form of raw material input. The process described in this paper overcomes these problems while retaining the strength of RP techniques. Technical challenges of the process are presented as well.

Harnessing the ability of RP techniques to control the internal morphology of the scaffold, it is possible to couple the design of the scaffold with controlled cell‐culture condition to modulate the behavior of the cells. However, this is just initial work, further development will be needed.

This method enables the designer to manipulate the scaffold at three different length scales, namely the macroscopic scale, intermediate scale and the cellular scale.

The work presented in this paper focuses on important processing steps for indirect scaffold fabrication using thermal‐sensitive natural biomaterial. A mathematical model is proposed to estimate the height of a printed line.