Design and Simulate Mixing of Compressed Natural Gas with Air in a Mixing Device

摘要

Gas mixer is a device used touddetermine the amount of natural gas and air beforeudentering the engine. It injects the gas into theudintake air stream of an internal combustionudchamber using a combination of radial holes andudradial tubes located around the perimeter of an airudflow passage. The size of intake air passage, theudnumber and size of the radial holes and tubesudvaries to achieve adequate gas or air mixing forudthe particular engine. Measurement of air flowudnecessary for engine operation is the selectionudcriteria of mixers. The power obtained fromudengine is dependent on the size of the mixer. Itudcan be seen from the experimental result that audsmaller mixer caused higher pressure at the throatudin compare to the analytical result. High pressureudcaused low velocity at the throat. Both smaller andudlarger mixer was able to promote the methane intoudthe outlet from the inlet tube. Smaller size throatudmixer at the throat restricted caused undesirableudresults. ud