The type of fuel, engine speed, and load are some of the parameters, which influence engine noise, vibrations, and exhaust emissions of an internal combustion engine. The present investigation is carried out to study the effect of isobutanol addition to methanol-gasoline blends on engine’s noise, vibration, and emission characteristics of an unmodified automotive SI engine operated at various engine speeds. The engine was fueled with 10 and 15% (v/v) blended fuels of methanol-gasoline (M10, M15) and methanol-isobutanol-gasoline (iBM10, iBM15). The blended fuels produced relatively high noise levels and less vibration in the vertical and longitudinal direction when compared with gasoline operation. The maximum noise level of 64.43dBA observed with the M15 blend and which is 4 dBA higher than gasoline. Only a slight variation in the total fuel consumption observed for all the test fuels at higher engine speeds. The emissions from the test fuels iBM10 and iBM15 showed a reduction in HC by 25 and 10% and CO emissions by 65 and 87%, respectively. The methanol-gasoline blends produced slightly higher CO₂ and NO_x emissions than gasoline.

燃料的类型，发动机速度和负载是一些参数，它们会影响发动机的噪声，振动和内燃机的废气排放。进行本研究以研究将异丁醇添加到甲醇-汽油混合物中对在各种发动机转速下运行的未改装汽车SI发动机的发动机噪声，振动和排放特性的影响。发动机使用甲醇汽油（M10，M15）和甲醇-异丁醇汽油（iBM10，iBM15）的10％和15％（v / v）混合燃料供油。与汽油运行相比，混合燃料产生相对较高的噪音水平，并且在垂直和纵向方向上振动较小。使用M15混合物观察到的最大噪音水平为64.43dBA，比汽油高4 dBA。在较高的发动机转速下，所有测试燃料的总燃料消耗仅略有变化。测试燃料iBM10和iBM15的排放分别使HC减少25％和10％，CO排放分别减少65％和87％。甲醇汽油混合物产生的二氧化碳略高₂和NO _X排放比汽油。