Mechanical Engineering Commons^™

Effects Of Air-Fuel Ratio And Operating Conditions On Particle Emissions From A Small Diesel Engine, Odinmma John-Paul Ofili

Master’s Theses

Automotive engineers typically increase the air-fuel ratio (AFR) of an engine to control the amount of smoke emitted, but it not quite known how this process affects particulate number (PN). In the work presented, AFR was independently varied to study its effects on PN. It was found that increasing the AFR reduced the concentrations of larger particles from 10⁸ #/cm³ to 10⁶ #/cm³ which is an effect observable as a reduction in smoke. However, the same increases in AFR only resulted in an energy specific PN change from 10¹⁵ #/kWh to 10¹⁴ #/kWh. The …

Test Cell Set-Up To Enable Drive-Cycle Testing Of A Variable Valve Actuation Enabled Camless Diesel Engine, Alexander Harrison Taylor

Open Access Theses

The previous facility which was used for engine testing at Purdue's Ray W. Herrick Laboratories utilized an eddy current dynamometer which is only suited for steady-state testing and throttle snaps. To better utilize a pre-existing camless diesel engine, which is is enabled via variable valve actuation, it was desired to perform transient drive-cycle tests. To accomplish this goal, a variable frequency drive AC dynamometer was required. Given that a brand new facility was constructed, the team was presented with an opportunity for ground up design of a test cell.

The new test cell's operation was proved out using a cammed …

The Effects Of Ivc Modulation On Modern Diesel Engines Equipped With Variable Valve Actuation At High Load And Speed, Troy E. Odstrcil, Gregory M. Shaver, Cody M. Allen

The Summer Undergraduate Research Fellowship (SURF) Symposium

Modern diesel compression engines are known for their increased durability, fuel economy and torque when compared with their spark ignition gasoline counterparts. These are some of the reasons why diesel engines are preferred in heavy duty applications such as trains and semi-trucks. During the Heavy Duty Federal Test Procedure transient drive cycle, or HDFTP, nearly 85% of the total fuel burned is at speeds greater than 2000 revolutions per minute (RPM) for the studied engine. Therefore, it is desirable to increase the fuel economy at these loads and speeds. It is hypothesized that the use of late intake valve close …