Sintered aluminium heat pipe (SAHP)

This work is the product of an ongoing PhD project in the School of the Built and Natural Environment of Northumbria University in collaboration with the University of Liverpool and Thermacore Europe Ltd. The achievements at the end of the first year are summarized. The main objective of the project is to develop an aluminum ammonia heat pipe with a sintered wick structure. Currently available ammonia heat pipes mainly use extruded axially grooved aluminum tubes as a capillary wick. There have been a few attempts of employing porous steel or nickel wicks in steel tubes with ammonia as the working fluid (Bai, Lin et al. 2009)although it is a common practice in loop heat pipes but there is no report of aluminum-ammonia heat pipes porous aluminium wick structures. The main barrier is the difficulty of sintering aluminum powders to manufacture porous wicks. So far during this project promising sintered aluminum heat pipe samples have been manufactured using the Selective Laser Melting (SLM) technique with various wick characteristics. This SLM method has proven to be capable of manufacturing very complicated wick structures with different thickness, porosity, permeability and pore sizes in different regions of a heat pipe. In addition the entire heat pipe including the end cap, outer tube wall, wick and the fill tube can be generated in a single process

Single-phase laminar flow heat transfer from confined electron beam enhanced surfaces

An experimental investigation of the thermal-hydraulic characteristics for single-phase flow through three electron beam enhanced structures was conducted with water at mass flow rates from 0.005 kg/s to 0.045 kg/s. The structures featured copper heat transfer surfaces, approximately 28 mm wide and 32 mm long in the flow direction, with complex three-dimensional (3D) electron beam manufactured pyramid-like structures. The channel height varied depending on the height of the protrusions and the tip clearance was maintained at 0.1-0.3 mm. The average protrusion densities for the three samples S1, S2, and S3 were 13, 11, and 25 per cm2 with protrusion heights of 2.5, 2.8, and 1.6 mm, respectively. The data gathered were compared to those for a smooth channel surface operating under similar conditions. The results show an increase up to approximately three times for the average Nusselt number compared with the smooth surface. This is attributed to the surface irregularities of the enhanced surfaces, which not only increase the heat transfer area but also improve mixing, disturb the thermal and velocity boundary layers, and reduce thermal resistance. The increase in heat transfer with the enhanced surfaces was accompanied by an increase of pressure drop, which has to be considered in design.The authors would like to acknowledge Dr Anita Buxton and Dr Bruce Dance of TWI for their contribution to this project and also EPSRC and TSB for funding the EngD programme and sponsoring the ASTIA collaborative research project that helped to develop the Electron Beam enhanced surfaces respectively

An ethnomethodological exploration of police officers’ use of a cognitive aid when encountering people with a potential mental disorder

Aim This study investigated a police officer’s situation awareness , when encountering a potentially mentally disordered person. This underpinned the development of a cognitive aid to support them during such encounters. Background Up to 40% of police encounters are associated with someone experiencing a mental disorder. Operational difficulties due to situational complexity, and the police officer’s ignorance regarding the features of mental disorder, often translate into flawed situation awareness. This study built upon the work of Wright et al. (2008) with Lancashire Constabulary. Method An ethnomethodological design was employed, viewed through the theoretical lenses of symbolic interactionism and Endsley’s (1988) situation awareness framework. Completed in two stages, stage one utilised narrative synthesis, and individual semi-structured interviews with eight police officers. Data was thematically analysed to identify emerging themes which underpinned the cognitive aid’s development. Stage two employed a pre-post-test design, utilising video vignettes, note-taking exercises, and focus group interviews with seventeen police officers. The cognitive aid was used operationally prior to conducting semi-structured interviews with ten police officers. Results Emergent themes identified that pre-encounter factors shaped police officers’ situation awareness. This governed their assessment of danger, often resulting in pre-set behaviours to control a situation. Police officers demonstrated improved situation awareness, recognising and responding to a greater range of features of mental disorder when they used the cognitive aid. Contribution of new knowledge This was the first study to explore a police officer’s situation awareness, when encountering a potentially mentally disordered person. It identifies features police officers associate with mental disorder. The findings highlighted the effect of pre-encounter factors and their influence upon the perception of danger. Significantly, the cognitive aid caused a paradigm shift from one defined by an assumption of criminality, to one defined by the interpersonal in which police officers recognised and responded to a person’s mental health and well-being

A study into different cell-level cooling strategies for cylindrical lithium-ion cells in automotive applications

Previous research has identified that the ageing rate and performance of lithium-ion cells is negatively influenced by unfavourable cell thermal conditions, specifically, high ambient temperatures and large in-cell temperature gradients. In this paper, the effectiveness of different cell cooling strategies on reducing the in-cell temperature gradient within cylindrical cells is analysed through the development of a 2-D transient bulk layer thermal model displaying anisotropic thermal conductivity. The model is validated against experimental temperature measurements in which the peak error of the simulation was found to be 2% and 5% for the experimental test drive cycle and constant 1C discharge respectively. Results indicate that radial cooling with air or singular tab cooling with liquid may be inadequate in limiting cell temperature gradients to below 5 ℃ for HEV type 32113 cells when subject to 4 loops of the US06 drive cycle

Thermal analysis of fin cooling large format automotive lithium-ion pouch cells

Conductively cooling the surface of lithium-ion pouch cells may simplify the external cooling mechanism, as heat transfer mediums are not routed across the cell surface. In this paper, the thermal performance of cooling cells with metallic fins is analysed using a developed test rig and thermal model. Results indicate that single edge fin cooling with aluminum sheets is effective in limiting surface temperature gradients to below circa 5℃ for cells subject to realistic EV and mild PHEV duty cycles. For aggressive track racing EV cycles, double edge fin cooling is required to limit surface temperature gradients to below 12℃

Mapping Alternative Impact: Alternative approaches to impact from co-produced research

No abstract available

Pool boiling on modified surfaces using R-123

This article has been made available through the Brunel Open Access Publishing Fund.Saturated pool boiling of R-123 was investigated for five horizontal copper surfaces modified by different treatments, namely, an emery-polished surface, a fine sandblasted surface, a rough sandblasted surface, an electron beam-enhanced surface, and a sintered surface. Each 40-mm-diameter heating surface formed the upper face of an oxygen-free copper block, electrically heated by embedded cartridge heaters. The experiments were performed from the natural convection regime through nucleate boiling up to the critical heat flux, with both increasing and decreasing heat flux, at 1.01 bar, and additionally at 2 bar and 4 bar for the emery-polished surface. Significant enhancement of heat transfer with increasing surface modification was demonstrated, particularly for the electron beam-enhanced and sintered surfaces. The emery-polished and sandblasted surface results are compared with nucleate boiling correlations and other published data. © 2014 Syed W. Ahmad, John S. Lewis, Ryan J. McGlen, and Tassos G. Karayiannis Published with license by Taylor & Francis

Pool boiling on modified surfaces using R-123

Paper presented at the 9th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Malta, 16-18 July, 2012.Saturated pool boiling of R-123 was investigated for five horizontal copper surfaces modified by different treatments, namely: an emery polished surface, a fine sandblasted surface, a rough sandblasted surface, an electron beam enhanced surface and a sintered surface. Each 40 mm diameter heating surface formed the upper face of an oxygen-free copper block, electrically heated by embedded cartridge heaters. The experiments were performed from the convective heat transfer regime to the critical heat flux, with both increasing and decreasing heat flux, at 1.01 bar, and additionally at 2 bar and 4 bar for the emery polished surface. Significant enhancement of heat transfer with increasing surface modification was demonstrated, particularly for the EB enhanced and sintered surfaces. The emery polished and sandblasted surface results are compared with nucleate boiling correlations and other published data.dc201

Hospital at home: a systematic review of how medication management is conceptualised, described and implemented in practice — a study protocol

Introduction Hospital at Home (H@H) is a method of healthcare delivery, where hospital level interventions are conducted in the patient’s usual place of residence, offering an alternative to hospital admission. This often includes the ability to perform point of care diagnostics and treat conditions using a range of treatments traditionally associated with hospital admission, including intravenous medicines and oxygen. H@H services have been established worldwide but there is a wide variation in definition and delivery models and currently no documented evidence supporting the delivery of medicines and medicines management within the H@H model. Therefore, this study aims to 1) describe how medication management in H@H is conceptulised, 2) describe and identify key components of medication management in H@H and 3) describe and identify variability in the implementation of medication management services within H@H models. Methods and analysis We will search a range of databases (PubMed, Medline, Embase, CINAHL), publicly accessible documents and expert recommendations. Studies, reports and policy documents published between 1st January 2000 and 31st January 2022 will be included. Two independent reviewers will 1) screen and select studies based on a priori inclusion/exclusion, 2) conduct quality assessment using the Mixed Methods Appraisal Tool on included studies and 3) extract data. Inductive thematic analysis (objectives 1 and 2), the SEIPS 2.0 model (objective 2) and the Consolidated Framework for Implementation Research (objective 3) will be used to synthesise data. Ethics and dissemination This systematic review will use secondary data sources from published documents, and as such research ethical approval was not required. We will disseminate the findings of this study in a peer-reviewed journal and national/international conference(s). Trial registration PROSPERO registration number: CRD42022300691. https://www.crd.york.ac.uk/ prospero/display_record.php?ID=CRD42022300691