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The purpose of this paper is to develop a cyclone with an internal electric field to capture dust and fine carbon particles with less than 5 μm diameter.

The cyclone collection efficiency model described by Cooper and Alley was used to design a conventional cyclone, which was later modified by introduction of the solenoid around it to introduce an electric field. The cyclone design performance was later established using ferrosilicon powder with less than 5 μm diameter.

The cyclone was found to have a particle collection efficiency of around 25 per cent for ferrosilicon powder before the introduction of the solenoid; the introduction of the solenoid increased the particle collection efficiency to around 50 per cent and the charging of the solenoid further increased the collection efficiency to 85 per cent at 2 kV DC and 97 per cent at 3 kV DC. When the cyclone was placed back on the gasifier system and supplied with 2 kV DC, it collected up to 270 g of fine carbon particles within 150 min of operation.

The major drawback was that the highest particle collection efficiency for the cyclone could only be achieved at very high voltage (3 kV) but this could not be supplied when the cyclone was back in the gasifier system due to air ionization that results in the corona effect.

The collection of very fine particles (less than 5 μm diameter) in hot gas streams is always a challenge, particularly in biomass gasifier systems. This resulted in a high cost of gas purification or initial investments in downstream processes. The developed cyclone could cut down this expenditure since most of the particles will not go beyond the cyclone.

Electrostatics has been applied in the development of gas cleaning devices, however most of these devices tend to be too cumbersome. The developed cyclone is based on the conventional design, which is less complicated and cheap to manufacture.

The Ba River catchment and delta on the island of Viti Levu, Fiji, supports a wealth of livelihoods and is populated by diverse communities who are living with an increased frequency and intensity of hydro-meteorological hazards (floods, cyclones and droughts). Participatory mapping as part of focus group discussions is a tool that can be used to elucidate communities’ understanding of the differing impacts of multiple hazards, as well as the strategies used to prepare and respond to different hazards. In this chapter, the authors present the results of qualitative research undertaken with members of three communities along the Ba River, from the Nausori highlands to the coastal mangroves, with a particular focus on recent floods (2009, 2012) and Tropical Cyclone Winston (2016). The communities draw on a wide range of livelihood strategies from fishing and agriculture to tourism and outside work. Natural hazard events vary in their impact on these livelihood strategies across the landscape and seascape, so that community members can adjust their activities accordingly. The temporal ‘signatures’ of ongoing impacts are also variable across communities and resources. The results suggest that taking a broad, landscape (and seascape) approach to understanding how communities draw livelihoods is valuable in informing effective and inclusive adaptation strategies for environmental change. Furthermore, documenting how the landscape is used in a mapped output may be a valuable tool for future social impact assessment for resource extraction activities.

Climate hazards in the form of cyclones are projected to become more intense under the pressures of future climate change. These changes represent a growing hazard to low lying coastal cities like Beira, Mozambique. In 2019, Beira experienced the devastating impact of Cyclone Idai. One of the many impacts resulting from this Cyclone was disrupted drinking water access. This investigation explores the distribution of Cyclone Idai’s impact on drinking water access via an environmental justice lens, exploring how preexisting water access characteristics may have predisposed households to the impacts of Cyclone Idai in Beria.

Relying on household survey data collected in Beira, the investigation applied a decision tree algorithm to investigate how drinking water disruption was distributed across the household survey sample using these preexisting vulnerabilities.

The investigation found that households that mainly relied upon piped water sources and experienced inconsistent access to water in the year prior to Cyclone Idai were more likely to experience disrupted drinking water access immediately after Cyclone Idai. The results indicate that residents in formal areas of Beira, largely reliant upon piped water supply, experienced higher rates of disrupted drinking water access following Cyclone Idai.

These findings question a commonly held assumption that informal areas are more vulnerable to climate hazards, like cyclones, than formal areas of a city. The findings support the inclusion of informal settlements in the design of climate change adaptation strategies.

Cyclone preparedness activities can significantly reduce household-related property damage and the negative knock-on effects. Research has found, however, that many people do not perform these behaviours. It is, therefore, important to understand why some people do, and others do not, perform such behaviours. This paper aims to investigate whether a commonly applied psychological theory of behaviour change can explain cyclone-specific preparedness behaviour.

This study used a cross-sectional survey design to examine the relationship between demographic factors, cyclone experience, psychological factors and preparedness behaviour. Informed by the protection motivation theory (PMT), it was hypothesised that perceived efficacy, perceived cost and self-efficacy would be the strongest predictors of preparedness behaviour. Data from 356 respondents living in a cyclone-prone region were analysed using multiple regression and mediation analysis with the PROCESS macro in SPSS.

In support of the hypothesis, it was found that perceived efficacy and perceived cost were the strongest psychological predictors of preparedness behaviour. Contradicting the hypothesis, however, self-efficacy was not a significant predictor of preparedness behaviour. Subsequent analysis indicated that people who have experienced cyclone damage perceive that preparedness measures are more effective for reducing damage, which, in turn, increases preparedness behaviour.

This paper provides empirical support for the application of the protective motivation theory for explaining cyclone-specific preparedness behaviour. More specifically, the results indicate that people are more likely prepare for cyclones if they perceive that preparedness activities are effective for reducing damage and are relatively inexpensive and easy to perform. The findings suggest that to promote cyclone preparedness, risk communicators need to emphasise the efficacy of preparedness and downplay the costs.

The concept of multi-purpose cyclone shelters has been found effective in saving various lives during past cyclones. The recent cyclone Amphan, which hit the Indian states of Odisha and West Bengal in the middle of pandemic COVID-19 has posed severe issues related to cyclone shelter management in the rural areas. The purpose of this paper is to investigate the case of Odisha in a pandemic and draw some key lessons of cyclone shelter management, which can be useful for future cascading risks in other parts of the country and the region.

Cyclone shelters are critical infrastructures in the management of cyclones, associated hazards and saving crucial lives. The effective management of shelters during emergencies is dependent on the existing institutional mechanism, local stakeholders and their understanding of the key functions of the emergency shelters. This paper reviews the key challenges through literature, reports and direct interviews of field professionals and practitioners.

In normal times, cyclone shelters are used as schools and their management lies with the local communities and/or elected bodies. Some of the key emerging issues include: the convincing population at risk for evacuation with proper care, existing emergency shelters being repurposed as COVID-19 facilities, need for hygiene and safety material, special arrangement and segregation of population at higher risk of COVID-19 and large destruction of social infrastructures.

During cascading disasters, adaptive governance becomes important. With the study of cyclones during the pandemic period, the paper draws key decision-making and governance points of cyclone shelter management. This case analysis can be useful to other similar situations during the prolonged pandemic time.

A new type of pneumatic parts feeding systems has been developed comprising a drum hopper, a jet inducer and a cyclone. A key feature of the system is the cyclone which, by means of the circulating streams, can correctly orientate parts.

The purpose of this paper is to propose an effective methodology for the industrial design of tangential inlet cyclone separators that is based on the fully three-dimensional (3D) simulation of the flow field within the cyclone coupled with an effective genetic algorithm.

The proposed fully 3D computational fluid dynamics (CFD) model makes use of the Reynold stress model for the accurate prediction of turbulence, while the particle trajectories are simulated using the one-way coupling discrete phase, which is a model particularly effective in case of low concentration of dust. To validate the CFD model, the numerical predictions are compared with experimental data available in the scientific literature. Eight design parameters were chosen, with the two objectives being the minimization of the pressure drop and the maximization of the collection efficiency.

The optimization procedure allows the determination of the Pareto Front, which represents the set of the best geometries and can be instrumental in taking an optimal decision in the presence of such a trade-off between the two conflicting objectives. The comparison among the individuals belonging to the Pareto Front with a more standard cyclone geometry shows that such a CFD global search is very effective.

The proposed procedure is tested for specific values of the operating conditions; however, it has general validity and can be used in place of typical procedures based on empirical models or engineers’ experience for the industrial design of tangential inlet cyclone separators with low solid loading.

Such an optimization process has never been proposed before for the design of cyclone separators; it has been developed with the aim of being both highly accurate and compatible with the industrial design time.

This purpose of the paper is to examine the multi-channel cyclone created at the Vilnius Gediminas Technical University (VGTU) Research Institute of Environmental Protection. The paper aims to predict the possible trajectories of solid particle motion in the cyclone with reference to the mechanical forces only.

The numerical calculations were performed on the basis of experimental results. The system of differential equations describing particle motion in the cyclone is analysed and numerically solved using Runge–Kutta–Fehlberg method. Research consists of three examples that illustrate the impact of particle density and velocity on collection and analyses the particle motion trajectories in the first and second channels of the cyclone.

Numerical calculations were performed according to the data from Vilnius Gediminas Technical University Research Institute of Environmental Protection. The particulate matter of wood ash and granite were used. The collection of solid particles of different size was examined when the air inflow velocity varies from 10 to 20 m/s. The possible motion trajectories of the solid particles are defined and the parameters of collected particles have been discussed.

The obtained results can be used for the analysis of air cleaning efficiency and particulate matter removal from air in a multi-channel cyclone.

The results lead us to improve the structure of the cyclone so as to effectively collect the solid particles of different size.

This paper presents the results obtained for the multi-channel cyclone created at the Vilnius Gediminas Technical University Research Institute of Environmental Protection.

The aim of this paper is to provide basic information on the types of particulate cyclones separators used in the chemical and process industries, their principles of operation and factors affecting their performance.

A general review of the types of particle cleaning cyclones used in the chemical and process industries was carried out and the principles guiding their operation and performance discussed. Information which could aid the choice of cyclone for new applications is also discussed.

It was concluded that the choice of cyclone for any application is associated with a trade‐off between two contrasting performance indicators (collection efficiency and pressure drop). Adequate and accurate data gathering is essential right from the design stage for smooth operation of cyclone.

The paper highlights the general principle of operation of cyclone separators and the factors that affect their performance.

This paper aims to discuss issues related to disaster mitigation planning provisions in Bangladesh, one of the most disaster‐prone countries in Asia. It seeks to concentrate on the issues related to the role of local groups in establishing cyclone shelters.

In February 2008, a field study was conducted in the Southwest coastal region of Bangladesh. Combining the most recent empirical data, the location of cyclone shelters and the social supremacy structure are explored in this paper. Vulnerability due to infrastructure is defined here on the basis of available infrastructural facilities i.e. cyclone shelters, by using catchment area analysis in the geographical information system (GIS) software ArcGIS. The paper bases its argument on the assumption that the location of an infrastructure item like a cyclone shelter is dependent on the influential and motivational power of local elites and not on the necessity of the deprived people. Vulnerability, from this perspective, is interpreted in this study as a result of socio‐political supremacy in establishing cyclone shelters in coastal regions of Bangladesh.

The results indicate that locally supreme groups are located the closest to the cyclone shelter and may control local‐level disaster mitigation planning.

The paper outlines the “social supremacy” concept based on one rural union and the communication rationalities of the general people. Both describe the ways of identification, the social spectrum of public interests as well as the decision‐making process in rural Bangladesh.

The paper contains valuable information regarding rural society and its socio‐political structure as well as planning problems in coastal Bangladesh.