This paper presented a novel electrohydrodynamic (EHD) micropump based on MEMS technology. The working mechanisms and classification of EHD micropump were introduced. The fabrication process of EHD micropump was prese...This paper presented a novel electrohydrodynamic (EHD) micropump based on MEMS technology. The working mechanisms and classification of EHD micropump were introduced. The fabrication process of EHD micropump was presented with the material selection,optimal design of microelectrode and assembly process. Static pressure experiments and flow experiments were carried out using different fluid and the channel depth. The results indicated that the micropump could achieve a maximum static pressure head of 268 Pa at an applied voltage of 90 V. The maximum flow rate of the micropump-driven fluid could reach 106 μL/min. This paper analyzed the future of combining micropump with heat pipe to deal with heat dissipation of high power electronic chips. The maximum heat dissipation capacity of 87 W/cm2 can be realized by vaporizing the micropump-driven liquid on vaporizing section of the heat pipe.展开更多
The ionic wind has good application prospects in the fields of air flow control and heat transfer enhancement. The key for successful applications is how to improve the velocity and how to increase the active area of ...The ionic wind has good application prospects in the fields of air flow control and heat transfer enhancement. The key for successful applications is how to improve the velocity and how to increase the active area of the ionic wind. This paper designed a needle array-mesh type electrohydrodynamic （EHD） gas pump. The use of needle array electrode where corona discharge started simultaneously could enlarge the active area. The velocity of the ionic wind could increase by placing several single-stage ionic wind generators in series appropriately, called as serial staged generator. The maximum average flow velocity of 16.1 m/s and volumetric flow of 303.5 L/min were achieved at the outlet of a 25-stage gas pump and the conversion efficiency was approximately 2.2%.展开更多
为了研究电流体动力学干燥技术中的物料厚度和横截面积对干燥特性的影响,以及建立比较适合的数学模型。分别以不同厚度和横截面积的熟牛肉为对象在温度为20℃-25℃,相对湿度为30±5%,周围风速为0 m/s的自然环境中进行电流体动力学...为了研究电流体动力学干燥技术中的物料厚度和横截面积对干燥特性的影响,以及建立比较适合的数学模型。分别以不同厚度和横截面积的熟牛肉为对象在温度为20℃-25℃,相对湿度为30±5%,周围风速为0 m/s的自然环境中进行电流体动力学干燥和对比试验;用Newton、Page、Modified Page、Henderson and Pabis、Logarithmic、Quadratic、Demir et al、Midilli et al等8种常用的薄层物料干燥的数学模型和均方根误差,约化卡方值,建模效率等3个统计参数对干燥数据进行了模拟和比较。结果表明,熟牛肉的厚度对干燥速度和干燥时间影响较大,熟牛肉的横截面积对干燥速度和干燥时间的影响较小;发现Logarithmic模型比较适合薄层熟牛肉的电流体动力学干燥。这将为优化电流体动力学干燥的工艺和提高干燥效率提供一些线索和实践指导。展开更多
In this Paper, we have proposed a new weighted residual method known as orthogonal collocation-based on mixed interpolation (OCMI). Mixed interpolation uses the classical polynomial approximation with two correction t...In this Paper, we have proposed a new weighted residual method known as orthogonal collocation-based on mixed interpolation (OCMI). Mixed interpolation uses the classical polynomial approximation with two correction terms given in the form of sine and cosine function. By these correction terms, we can control the error in the solution. We have applied this approach to a non-linear boundary value problem (BVP) in ODE which governs the electrohydrodynamic flow in a cylindrical conduit. The solution profiles shown in the figures are in good agreement with the work of Paullet (1999) and Ghasemi et al. (2014). Our solution is monotonic decreasing and satisfies , where, α governs the strength of non-linearity and for large values of α solutions are . The residual errors are given in Table 1 and Table 2 which are significantly small. Comparison of residual errors between our proposed method, Least square method and Homotopy analysis method is also given and shown via the Table 3 where as the profiles of the residual error are depicted in Figures 4-8. Table and graphs show that efficiency of the proposed method. The error bound and its L2-norm with relevant theorems for mixed interpolation are also given.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.50676001)
文摘This paper presented a novel electrohydrodynamic (EHD) micropump based on MEMS technology. The working mechanisms and classification of EHD micropump were introduced. The fabrication process of EHD micropump was presented with the material selection,optimal design of microelectrode and assembly process. Static pressure experiments and flow experiments were carried out using different fluid and the channel depth. The results indicated that the micropump could achieve a maximum static pressure head of 268 Pa at an applied voltage of 90 V. The maximum flow rate of the micropump-driven fluid could reach 106 μL/min. This paper analyzed the future of combining micropump with heat pipe to deal with heat dissipation of high power electronic chips. The maximum heat dissipation capacity of 87 W/cm2 can be realized by vaporizing the micropump-driven liquid on vaporizing section of the heat pipe.
基金supported by National Natural Science Foundation of China(No.50577053)
文摘The ionic wind has good application prospects in the fields of air flow control and heat transfer enhancement. The key for successful applications is how to improve the velocity and how to increase the active area of the ionic wind. This paper designed a needle array-mesh type electrohydrodynamic （EHD） gas pump. The use of needle array electrode where corona discharge started simultaneously could enlarge the active area. The velocity of the ionic wind could increase by placing several single-stage ionic wind generators in series appropriately, called as serial staged generator. The maximum average flow velocity of 16.1 m/s and volumetric flow of 303.5 L/min were achieved at the outlet of a 25-stage gas pump and the conversion efficiency was approximately 2.2%.
文摘为了研究电流体动力学干燥技术中的物料厚度和横截面积对干燥特性的影响,以及建立比较适合的数学模型。分别以不同厚度和横截面积的熟牛肉为对象在温度为20℃-25℃,相对湿度为30±5%,周围风速为0 m/s的自然环境中进行电流体动力学干燥和对比试验;用Newton、Page、Modified Page、Henderson and Pabis、Logarithmic、Quadratic、Demir et al、Midilli et al等8种常用的薄层物料干燥的数学模型和均方根误差,约化卡方值,建模效率等3个统计参数对干燥数据进行了模拟和比较。结果表明,熟牛肉的厚度对干燥速度和干燥时间影响较大,熟牛肉的横截面积对干燥速度和干燥时间的影响较小;发现Logarithmic模型比较适合薄层熟牛肉的电流体动力学干燥。这将为优化电流体动力学干燥的工艺和提高干燥效率提供一些线索和实践指导。
文摘In this Paper, we have proposed a new weighted residual method known as orthogonal collocation-based on mixed interpolation (OCMI). Mixed interpolation uses the classical polynomial approximation with two correction terms given in the form of sine and cosine function. By these correction terms, we can control the error in the solution. We have applied this approach to a non-linear boundary value problem (BVP) in ODE which governs the electrohydrodynamic flow in a cylindrical conduit. The solution profiles shown in the figures are in good agreement with the work of Paullet (1999) and Ghasemi et al. (2014). Our solution is monotonic decreasing and satisfies , where, α governs the strength of non-linearity and for large values of α solutions are . The residual errors are given in Table 1 and Table 2 which are significantly small. Comparison of residual errors between our proposed method, Least square method and Homotopy analysis method is also given and shown via the Table 3 where as the profiles of the residual error are depicted in Figures 4-8. Table and graphs show that efficiency of the proposed method. The error bound and its L2-norm with relevant theorems for mixed interpolation are also given.
