Magnetic damping of levitated liquid droplets in AC and DC field

The intense AC magnetic field required to produce levitation in terrestrial conditions, along with the buoyancy and thermo-capillary forces, results in turbulent convective flow within the droplet. The use of a homogenous DC magnetic field allows the convective flow to be damped. However the turbulence properties are affected at the same time, leading to a possibility that the effective turbulent damping is considerably reduced. The MHD modified K-Omega turbulence model allows the investigation of the effect of magnetic field on the turbulence. The model incorporates free surface deformation, the temperature dependent surface tension, turbulent momentum transport, electromagnetic and gravity forces. The model is adapted to incorporate a periodic laser heating at the top of the droplet, which have been used to measure the thermal conductivity of the material by calculating the phase lag between the frequency of the laser heating and the temperature response at the bottom. The numerical simulations show that with the gradual increase of the DC field the fluid flow within the droplet is initially increasing in intensity. Only after a certain threshold magnitude of the field the flow intensity starts to decrease. In order to achieve the flow conditions close to the ‘laminar’ a D.C. magnetic field >4 Tesla is required to measure the thermal conductivity accurately. The reduction in the AC field driven flow in the main body of the drop leads to a noticeable thermo-capillary convection at the edge of the droplet. The uniform vertical DC magnetic field does not stop a translational oscillation of the droplet along the field, which is caused by the variation in total levitation force due to the time-dependent surface deformation.

Foundations for paramedic practice: a theoretical perspective

Written by leading paramedics and academic subject experts, with a foreword by Paul Bates, this is the first foundation level text to introduce the main theoretical subjects studied on the new higher education paramedic science programmes. It underpins practice and links ways of working to the crucial theory base. The numerous examples and case studies focus specifically on pre-hospital and emergency care. Key topics covered include: * NHS and ambulance service history * Ethics and law for the paramedic * Communication and reflective practice * Professional issues, including evidence-based practice, anti-discriminatory practice, clinical governance and clinical audit * Psychological perspectives on health and ill health * Safeguarding children * Sociological perspectives on health and ill health and social policy * Managing change and leadership theory * Continuing professional development The text prompts you to stop and think about what you have just read and relate this to your role. Throughout the book, the author carefully considers how the theory being discussed relates to the role of the ambulance clinician. Foundations for Paramedic Practice: A Theoretical Perspective is a core text for students of paramedic science and will also provide a valuable resource for students of allied health professions. This text provides a stepping stone to further reading and investigation. - Taken from the back cover of: Amanda Blaber - Foundations for paramedic practice: a theoretical perspective