进气门

Abstract—In-cylinder flow field structure in an internalcombustion (I.C) engine has a major influence on the combustion,emission and performance characteristics. Fluid enters thecombustion chamber of an I.C engine through the intake manifoldwith high velocity. Then the kinetic energy of the fluid resulting inturbulence causes rapid mixing of fuel and air, if the fuel is injecteddirectly into the cylinder. With optimal turbulence, better mixing offuel and air is possible which leads to effective combustion. A goodknowledge of the flow field inside the cylinder of an I.Cengine is very much essential for optimization of the designof the combustion chamber for better performance especiallyin modern I.C engines like gasoline direct injection (GDI),homogeneous charge compression ignition (HCCI)engines.The main objective of this work is to study the incylinderfluid flow field characteristics of a single-cylinderengine to see the effect of intake manifold inclination atequivalent rated engine speed using Particle ImageVelocimetry (PIV) under various static intake valve liftconditions. To facilitate the PIV experiments, the metal cylinder ofthe engine was replaced by a transparent one. For every operatingtest condition, 50 image pairs were captured and processed usingDAVIS software. From the results, it is seen that the in-cylinderflow structure is greatly influenced by the intake manifoldinclinations irrespective of intake valve lift. Maximum TurbulentKinetic Energy (TKE) was highest at full intake valve liftirrespective of the inclination. Also, the maximum TKE wasthe highest for 600 intake manifold inclination compared toother inclinations irrespective of the intake valve lift atequivalent rated engine speed. Finally, it is concluding thatthe analysis carried in this work is useful in predicting theflow and inturn optimizing combustion chamber of modernI.C engines.

关闭门窗、通风系统24小时后，室内TVOC浓度主卧为0.52mg/m3，客厅为0.50mg/m3； 关闭门窗、开启通风系统后，室内TVOC浓度主卧为0.37mg/m3，客厅为0.35mg/m3； 关闭通风系统、开启门窗后，室内TVOC浓度主卧为0.33mg/m3，客厅为0.34mg/m3； 按国家标准《GB/T18883-2002 室内空气质量标准》中，TVOC的标准值为0.60mg/m3，室内释放的TVOC浓度未超标。综上所述，开启门窗与通风系统，经常保持通风换气，均有利于TVOC的扩散，减少室内TVOC浓度。

按国家标准《GB/T18883-2002 室内空气质量标准》中，TVOC的标准值为0.60mg/m3，室内释放的TVOC浓度未超标。综上所述，开启门窗与通风系统，经常保持通风换气，均有利于TVOC的扩散，减少室内TVOC浓度。

关闭门窗、通风系统24小时后，室内甲醛浓度主卧为20ppb，客厅为15ppb；关闭门窗、开启通风系统后，室内甲醛浓度主卧为13ppb，客厅为10ppb；关闭通风系统、开启门窗后，室内甲醛浓度主卧为10ppb，客厅为10ppb；按国家标准《GB/T18883-2002 室内空气质量标准》中，甲醛的标准值为80ppb，室内释放的甲醛浓度未超标。

目的:评价野生白术与栽培白术的品质。方法:通过电子鼻检测不同白术气味在传感器上的响应值,并采用主成分( PCA) 、判别因子(DFA)及统计质量控制法( SQC)进行分析。结果:野生白术与栽培白术气味差异明显 浙江磐安白术、安徽祁门引种的浙白术及阳生环境栽培的野生白术气味相近 湖北咸丰、江西修水等地白术及苍术与其它白术的气味差异较大。结论:电子鼻技术对白术气味的判别与传统经验鉴别相一致,电子鼻技术结合数学模型可以作为中药质量鉴别手段