Numerical investigation of optimal geometry parameters for ejectors of premixed burner

An ejector of low NO~ burner was designed for a gas instantaneous water heater in this work. The flowing and mixing process of the ejector was investigated by computational fluid dynamics （CFD） approach. A comprehensive study was conducted to understand the effects of the geometrical parameters on the static pressure of air and methane, and mole fraction uniformity of methane at the outlet of ejector. The distribution chamber was applied to balance the pressure and improve the mixing process of methane and air in front of the fire hole. A distribution orifice plate with seven distribution orifices was introduced at the outlet of the ejector to improve the flow organization. It is found that the nozzle exit position of 5 mm and nozzle diameter d 〉1.3 mm should be used to improve the flow organization and realize the well premixed combustion for this designed ejector.

刻录软件大评比

说到刻录，很多人首先想到的就是Nero Burning Rom或Alcohol 120％这类知名软件，但是常言说得好——“术业有专攻”，每款刻录软件针对的应用是不同的．当我们需要将MP3转为CD，或者是制作自动运行光盘以及加密光盘时．我们又该选择何种刻录软件呢，为此笔者特意试用了多款现在最常见的刻录软件．再从中抽选出最具特色的软件介绍给大家，相信看完此文以后，你在刻录时就不会茫然了。