In this paper, a 3D model of a flat circuit board with a heat generating electronic chip mounted on it has been studied numerically. The conjugate heat transfer including the conduction in the chip and convection with...In this paper, a 3D model of a flat circuit board with a heat generating electronic chip mounted on it has been studied numerically. The conjugate heat transfer including the conduction in the chip and convection with the surrounding fluid has been investigated numerically. Computational fluid dynamics using the finite volume method has been used for modeling the conjugate heat transfer through the chip and the circuit board. Conjugate heat transfer has broad applications in engineering and industrial applications in design of cooling off electronic components. Effects of various inlet velocities have been studied on the heat transfer variation and temperature of the circuit board. Numerical results show that the temperature of the chip reduces as the velocity of the inlet fluid flow increases.展开更多
本文介绍了一种防火报警系统用的高效率智能型600 W D类音频功率放大器系统的设计.该系统通过内嵌Linux操作系统管理并可接入大型的防火报警系统.通过使用基于新型氮化镓功率管的无整流桥型功率因子校正电路,该系统的功率因子达到99.6%...本文介绍了一种防火报警系统用的高效率智能型600 W D类音频功率放大器系统的设计.该系统通过内嵌Linux操作系统管理并可接入大型的防火报警系统.通过使用基于新型氮化镓功率管的无整流桥型功率因子校正电路,该系统的功率因子达到99.6%,整个系统满载时的效率达90%.通过采用恰当的脉宽调制器载波频率和Lanczos内插方法简化了采样率转换滤波器、内插滤波器和脉宽调制器的硬件设计.展开更多
文摘In this paper, a 3D model of a flat circuit board with a heat generating electronic chip mounted on it has been studied numerically. The conjugate heat transfer including the conduction in the chip and convection with the surrounding fluid has been investigated numerically. Computational fluid dynamics using the finite volume method has been used for modeling the conjugate heat transfer through the chip and the circuit board. Conjugate heat transfer has broad applications in engineering and industrial applications in design of cooling off electronic components. Effects of various inlet velocities have been studied on the heat transfer variation and temperature of the circuit board. Numerical results show that the temperature of the chip reduces as the velocity of the inlet fluid flow increases.
文摘本文介绍了一种防火报警系统用的高效率智能型600 W D类音频功率放大器系统的设计.该系统通过内嵌Linux操作系统管理并可接入大型的防火报警系统.通过使用基于新型氮化镓功率管的无整流桥型功率因子校正电路,该系统的功率因子达到99.6%,整个系统满载时的效率达90%.通过采用恰当的脉宽调制器载波频率和Lanczos内插方法简化了采样率转换滤波器、内插滤波器和脉宽调制器的硬件设计.
