Development of a Multi-Segment Parallel Compressor Model for a Boundary Layer Ingesting Fuselage Fan Stage

The present methodological study aims to assess boundary layer ingestion (BLI) as a promising method to improve propulsion efficiency. BLI utilizes the low momentum inflow of the wing or fuselage boundary layer for thrust generation in order to minimize the required propulsive power for a given amount of thrust for wing or fuselage-embedded engines. A multi-segment parallel compressor model (PCM) is developed to calculate the power saving from full annular BLI as occurring at a fuselage tail center-mounted aircraft engine, employing radially subdivided fan characteristics. Applying this methodology, adverse effects on the fan performance due to varying inlet distortions depending on flight operating point as well as upstream boundary layer suction can be taken into account. This marks one step onto a further segmented PCM model for general cases of BLI-induced inlet distortion and allows the evaluation of synergies between combined BLI and active laminar flow control as a drag reduction measure. This study, therefore, presents one further step towards lower fuel consumption and, hence, a lower environmental impact of future transport aircraft.

Analysis of Greenhouse Gas Emission From Aircrafts and Ground Service Equipment at Tribhuvan International Airport of Nepal

This paper highlights the trend of carbon dioxide emission and its reduction measure at Tribhuvan International Airport, which is the only international airport of Nepal. The landing and take-off (LTO) cycle of three-year (2016 to 2018) data were gathered from Civil Aviation Authority of Nepal (CAAN) for all types of aircrafts and fuel consumption data of each ground service equipment (GSE) were collected from Nepal Airlines Corporation (NAC). With the help of LTO emission factors published by different institutions and collected data, the emission was calculated and overall (international, domestic, helicopters and GSE) CO₂ emission in the year 2016, 2017 and 2018 was found to be 56.55, 65.66 and 71.89 Kilotonnes respectively. Upon validation of calculated emission the discrepancy of 2.59% was found. The CO₂ emission was forecasted up-to 2030 considering two scenarios namely, time series analysis and regression analysis. Lastly, for the CO₂ reduction from GSE the scenario; Electrical GSE and Construction of Aerobridge was studied and from which it was found that the CO₂ will be reduced by 80% if implemented.

Low-cost assessment of a stove improvement program in Peru

Background: Approximately 3 billion people worldwide, including more than 20 million people in Peru alone, depend on biomass fuels (BMF) for heating and boiling water, cooking, and lighting their homes. Burning BMF on poorly ventilated stoves results in household air pollution (HAP), which includes carbon monoxide (CO). Stove improvement programs aim to reduce indoor air pollution and are included in various organizations’ education visits to Peru. The programs do not allow sufficient time, or provide equipment or skills training to determine if the stove improvements have been successful.Objective: To develop and implement a rapid, low-cost method to measure CO concentrations in rural Peruvian households in order to assess the success of stove improvements. Methods: CO concentrations were measured 159 times in 14 households (with 7 clean, 6 traditional, and 1 gas stove) near Cusco, Peru. CO concentrations were measured in one-minute intervals with MSA Altair 4X multigas monitors. The likelihood of the 95th percentile exceeding the NIOSH CO ceiling limit of 200 ppm for each stove type was calculated.Results: The probability of overexposure was almost three times lower with “clean” stoves than with traditional stoves, i.e., 24% vs 9%.Conclusion: A promising and pragmatic method to evaluate the increased effectiveness of clean stoves over traditional ones was developed and tested. This method supports the implementation of clean stoves as a risk reduction measure.

Peer-assisted injection as a harm reduction measure in a supervised consumption service: a qualitative study of client experiences

Background Peer assistance is an emerging area of study in injection drug use. When Canada’s first supervised consumption site (SCS) opened in 2003 in Vancouver, Canada, clients were prohibited from injecting their peers; only recently has this practise been introduced as a harm reduction measure at these sites. In 2018, Health Canada granted federal exemption to allow peer-assisted injection at certain SCS sites, under the Controlled Drugs and Substances Act. Literature pertaining to peer-assisted injection addresses several topics: interpersonal relationships between the injection provider and recipient; the role of pragmatism; trust and expertise; and gender relations. Methods In this qualitative study, participants (n = 16) were recruited to be interviewed about their experiences in a peer-assisted injection program (PAIP) at one SCS regulated by Health Canada. Interview data were transcribed and thematically analyzed. Quantitative administrative data were used to provide context and to describe the study population, comprised of people in the PAIP (n = 248). Results PAIP clients made up 17.4% of all SCS clients. PAIP clients were more likely to be female and Indigenous. Injection providers expressed being moved by compassion to help others inject. While their desire to assist was pragmatic, they felt a significant burden of responsibility for the outcomes. Other prominent factors related to the injection provider-recipient relationship were social connection, trust, safety, social capital, and reciprocity. Participants also made suggestions for improving the PAIP which included adding more inhalation rooms so that if someone was unable to inject they could smoke in a safe place instead. Additionally, being required by law to divide drugs outside of the SCS, prior to preparing and using in the site, created unsafe conditions for clients. Conclusions Regular use of the SCS, and access to its resources, enabled participants to lower their risk through smoking and to practice lower-risk injections. At the federal level, there is considerable room to advocate for allowing clients to divide drugs safely within the SCS, and to increase capacity for safer alternatives such as inhalation.

Study on slagging characteristics and prevention of biomass briquette

It is a high efficiency，energy-saving and emission reduction measure to replace coal with biomass briquette fuel in a layer combustion furnace, but in the combustion process, the serious slagging problem has been restricted the promotion of biomass fuel. By analyzing the combustion characteristics of biomass briquette, the ash fusion characteristics and slagging mechanism, combined with the combustion characteristics of a layer combustion furnace, the important influence of key combustion parameters (furnace temperature, excess air, fuel layer thickness) on the slagging in the furnace is obtained, which provides a scientific basis for taking measures to prevent and control the slagging in the design and operation of the biomass briquette layer combustion furnace.

Peer-Assisted Injection as a Harm Reduction Measure in a Supervised Consumption Service: A Qualitative Study of Client Experiences

Background: Peer assistance is an emerging area of study in injection drug use. When Canada’s first supervised consumption site (SCS) opened in 2003 in Vancouver, BC, clients were prohibited from injecting their peers; only recently has this practice been introduced as a harm reduction measure at these sites. In 2018, Health Canada granted federal exemption to allow peer-assisted injection at certain SCS sites, under the Controlled Drugs and Substances Act. Literature pertaining to peer-assisted injection addresses several topics: interpersonal relationships between the injection provider and recipient; the role of pragmatism; trust and expertise; and gender relations. Methods: In this qualitative study, participants (n=16) were recruited to be interviewed about their experiences in a peer-assisted injection program (PAIP) at one SCS regulated by Health Canada. Interview data were transcribed and thematically analyzed. Quantitative administrative data was used to provide context and to describe the study population, comprised of people in the PAIP (n=248) Results: PAIP clients made up 17.4% of all SCS clients. PAIP clients were more likely to be female and Indigenous. Injection providers expressed being moved by compassion to help others inject. While their desire to assist was pragmatic, they felt a significant burden of responsibility for the outcomes. Other prominent factors related to the injection provider-recipient relationship were social connection, trust, safety, social capital, and reciprocity. Participants also made suggestions for improving the PAIP which included adding more inhalation rooms so that if someone was unable to inject they could smoke in a safe place instead. Additionally, being required by law to divide drugs outside of the SCS, prior to preparing and using in the site, created unsafe conditions for clients. Conclusions: Regular use of the SCS, and access to its resources, enabled participants to lower their risk through smoking and to practise lower-risk injections. At the federal level, there is considerable room to advocate for allowing clients to divide drugs safely within the SCS, and to increase capacity for safer alternatives such as inhalation.