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Dehumidification at rates from 20 to 24,000 kg/24 hours using simple absorption process … humidity levels in power stations reduced below 40% … corrosion and pitting of components prevented.

Explains the problems, often unrecognized by engineers, which can be caused by excessive humidity in manufacturing, and identifies the confusion surrounding the measurement of humidity, which may account for the low level of recognition. Reports on the measures being taken to eliminate that confusion and some of the instruments currently available to measure humidity. Outlines the main technologies available to correct excess humidity and their qualities.

DEHUMIDIFYING systems manufactured by AB Carl Munters, Sweden, which exploit the fact that corrosion does not occur where relative humidity (RH) is below 50% (Fig. 1), are now being used by the Danish and Swedish air forces, who have found that they improve the operational performance of in‐service aircraft to the extent that 18 aircraft can now do the work of 19. (Similar systems have been supplied by Munters since the 1950s for the protection of stored military equipment and supplies.)

During the past several years, research and studies in the field of solar energy have been continuously increased. One of the substantial applications of solar energy is related to industrial utilization for the drying process by efficient heat transfer methods. This study aims to upgrade the overall performance of an indirect solar dryer using a solar absorber extension tube (SET) equipped with ball-type turbulators.

In this work, three various SETs including hollow (SET Type 1), 6-balls (SET Type 2) and 10-balls (SET Type 3), have been simulated using Fluent software to evaluate heat transfer characteristics and flow structure along the air passage. Then, the modified solar drying system has been manufactured and tested at different configurations.

The findings indicated that adding a SET improved the performance notably. According to the results, using turbulators in the tube has a positive effect on heat transfer. The highest overall thermal efficiency was found in the range of 51.47%–64.71% for the system with SET Type 3. The maximum efficiency increment of the system was found as 19% with the use of SET. Also, the average specific moisture extraction rate, which is a significant factor to survey the effectiveness of the dehumidification system was found between 0.20 and 0.38 kg kWh⁻¹.

In the present study, a novel SET has been developed to upgrade the performance of the solar dehumidifier. This new approach makes it possible to improve both thermal and drying performances.

The lack of reference architecture for Internet of Things (IoT) modeling impedes the successful design and implementation of an IoT-based production logistics and supply chain system (PLSCS). The authors present this study in two parts to address this research issue. Part A proposes a unified IoT modeling framework to model the dynamics of distributed IoT processes, IoT devices, and IoT objects. The models of the framework can be leveraged to support the implementation architecture of an IoT-based PLSCS. The second part (Part B) of this study extends the discussion of implementation architecture proposed in Part A. Part B presents an IoT-based cyber-physical system framework and evaluates its performance. The paper aims to discuss this issue.

This paper adopts a design research approach, using ontology, process analysis, and Petri net modeling scheme to support IoT system modeling.

The proposed IoT system-modeling approach reduces the complexity of system development and increases system portability for IoT-based PLSCS. The IoT design models generated from the modeling can also be transformed to implementation logic.

The proposed IoT system-modeling framework and the implementation architecture can be used to develop an IoT-based PLSCS in the real industrial setting. The proposed modeling methods can be applied to many discrete manufacturing industries.

The IoT modeling framework developed in this study is the first in this field which decomposes IoT system design into ontology-, process-, and object-modeling layers. A novel implementation architecture also proposed to transform above IoT system design models into implementation logic. The developed prototype system can track product and different parts of the same product along a manufacturing supply chain.

In the past, the RAF’s approach to corrosion was reactive: corrosion occurred, was identified and then rectified. Such a strategy is no longer acceptable, as corrosion rectification is costly both in terms of material and aircraft availability. More importantly, as escalating replacement costs force us to retain aircraft in service for ever‐longer periods, the threat posed to structural integrity by corrosion and repeated corrosion repairs can no longer be tolerated. Consequently, the RAF has had no option but to develop a policy of corrosion prevention. Aerospace Maintenance, Development and Support, part of Headquarters Royal Air Force Logistics Command, has therefore been actively involved with the evaluation and trialling of a range of important corrosion prevention techniques that are compatible with the RAF’s current stance. Aircraft washing and rinsing practices have been reviewed to confirm their effectiveness, and trials have shown that dehumidified air permeates readily through a full‐size airframe, reducing relative humidity and arresting the rate of corrosion. From our work we have concluded that effective washing should be supported, where possible, by freshwater rinsing, and, if a cost effective system can be developed, structural dehumidification should also be practised. Notwithstanding a policy of corrosion prevention, we know that we operate aircraft that have already accumulated corrosion damage which has to be located and recorded. Non‐destructive testing is employed widely, and the use of information derived from the process to populate structural databases is being explored. Additionally, we are involved with refining the methodologies associated with structural inspections to ensure the ongoing integrity of our ageing aircraft fleets.

The purpose of this paper is to examine the modeling of simultaneous heat and mass transfer under dehumidifying conditions. Moist air cooling in tube‐fin exchangers is investigated using a finite element technique.

The model requires the solution of a conjugate problem, since interface temperatures must be calculated at the same time as temperature distributions in adjacent fluid and solid regions. The energy equation is solved in the whole domain, including the solid region, and the latent heat flux on the surfaces where condensation takes place is taken into account by means of an additional internal boundary condition.

Thermal performances for different Reynolds numbers of a typical two‐row tube‐fin exchanger are numerically analysed, for both in‐line and staggered arrangements of tubes. The results justify the great importance that the ratio between latent and overall rates of heat transfer has in the design of compact heat exchangers.

In this work, the capabilities of the proposed methodology to deal with industrial applications in the field of compact exchangers are outlined.

The paper presents an effective approach to the solution of conjugate conduction and convection problems with simultaneous heat and mass transfer. The formulation is completely general, even if the finite element method is used in the calculations.