The main theme of the current article is to investigate the heat transfer in the pulsatile flow of an electrically conducting viscous fluid in a constricted channel under the effect of the magnetic field and thermal r...The main theme of the current article is to investigate the heat transfer in the pulsatile flow of an electrically conducting viscous fluid in a constricted channel under the effect of the magnetic field and thermal radiation.The unsteady governing equations simplified for low conducting fluids are solved numerically by finite difference method using stream-vorticity function formulation.The influence of the flow parameters such as the Hartmann number(magnetic parameter),Strouhal number(flow pulsation parameter),Prandtl number,and radiation parameter is studied on the relevant flow profiles.The influence of different emerging parameters on the skin friction coefficient and Nusselt number are examined,as well.In general,the profiles are observed to exhibit a relatively more regular pattern upstream of the construction than that downstream of the constriction.展开更多
OBJECTIVE: To investigate a quantitative method for using radial artery pulse waveforms to assess the effect of pulsatile flow during cardiopulmonary bypass(CPB).METHODS: A total of 34 adults with heart disease who un...OBJECTIVE: To investigate a quantitative method for using radial artery pulse waveforms to assess the effect of pulsatile flow during cardiopulmonary bypass(CPB).METHODS: A total of 34 adults with heart disease who underwent open-heart surgery between April2010 and January 2011 were randomized into a pulsatile perfusion group(n=17) and a non-pulsatile perfusion group(n=17). Radial arterial pulse waveforms of pulsatile and non-pulsatile perfusion patients were observed and compared before and during CPB.RESULTS: No pulse waveform could be detected at patients' radial artery in both groups when the aorta was cross-clamped. Pulse waveforms could be detected at pulsatile perfusion patients' radial artery, but could not be detected at non-pulsatile perfusion patients' radial artery during CPB. Additionally, patients' pulse waveforms during pulsatile perfusion were lower than those before the operation.CONCLUSION: Our findings indicate that radial artery sphygmogram can be used as a valid indicator to evaluate the effectiveness of pulsatile perfusion during CPB.展开更多
文摘The main theme of the current article is to investigate the heat transfer in the pulsatile flow of an electrically conducting viscous fluid in a constricted channel under the effect of the magnetic field and thermal radiation.The unsteady governing equations simplified for low conducting fluids are solved numerically by finite difference method using stream-vorticity function formulation.The influence of the flow parameters such as the Hartmann number(magnetic parameter),Strouhal number(flow pulsation parameter),Prandtl number,and radiation parameter is studied on the relevant flow profiles.The influence of different emerging parameters on the skin friction coefficient and Nusselt number are examined,as well.In general,the profiles are observed to exhibit a relatively more regular pattern upstream of the construction than that downstream of the constriction.
基金Grants from the National Natural Science Foundation of China(No.81173200,No.81373556)the Research and Assessment of the Effects of Pulsatile Perfusion During Cardiopulmonary Bypass Based on the Monitoring"Cunkou"Pulse Waveforms of Traditional Chinese Medicine Research Fund of Shanghai Municipal Public Health Bureau(No.2010J015A)
文摘OBJECTIVE: To investigate a quantitative method for using radial artery pulse waveforms to assess the effect of pulsatile flow during cardiopulmonary bypass(CPB).METHODS: A total of 34 adults with heart disease who underwent open-heart surgery between April2010 and January 2011 were randomized into a pulsatile perfusion group(n=17) and a non-pulsatile perfusion group(n=17). Radial arterial pulse waveforms of pulsatile and non-pulsatile perfusion patients were observed and compared before and during CPB.RESULTS: No pulse waveform could be detected at patients' radial artery in both groups when the aorta was cross-clamped. Pulse waveforms could be detected at pulsatile perfusion patients' radial artery, but could not be detected at non-pulsatile perfusion patients' radial artery during CPB. Additionally, patients' pulse waveforms during pulsatile perfusion were lower than those before the operation.CONCLUSION: Our findings indicate that radial artery sphygmogram can be used as a valid indicator to evaluate the effectiveness of pulsatile perfusion during CPB.
