<div>With the continuous upgrading of emission regulations for internal combustion engines, nitrogen oxide treatment capacity selective catalytic reduction (SCR) aftertreatment needs to be continuously improved. In this study, based on a prototype SCR aftertreatment, impact arrangement key components in system (urea injector, mixer, and catalyst unit) ammonia uniformity was investigated. First, parameterized designs urea unit were conducted. Then, using computational fluid dynamics...

A conventional asymmetric twin-scroll turbine with wastegate is capable of effectively tackling down the contradiction between fuel economy degradation and low nitrogen oxide emissions. However, as engine speed has been rising at middle- high-speed ranges, pressure small scroll inlet will be increasingly higher compared intake pressure, thereby worsening economy. In this study, a novel turbocharging technology balance valve was first analyzed to more emission. The experiments on test rig...

The operation mode of an asymmetric twin-scroll turbine is significantly different from that a steady state under exhaust pulse feeding conditions, which leads to more complex matching between with engine. In this paper, It was first studied the effect flow area ratio wheel on energy distribution turbocharged engines. Firstly, compared deviation average efficiency time testing results and cycle based high frequency test background in scheduling engines, as well method weight proposed....

Abstract In this paper, a novel one-dimensional matching method of an asymmetric twin-scroll turbine (ATST) with small scroll bypass wastegate is initially presented for energy improvement. The developed presents further insights into efficiency prediction the ATST and exhaust in process model characterization. large turbines was approximately assessed two times flow parameters turbines, respectively, as well according to curves. Subsequently, given results 9-L engine, targeted developed;...

Maintaining required performance and rated power output of proton exchange membrane fuel cells while reducing consumption demands improving efficiencies at the largest parasitic work loss contributor, namely air compressor. In this paper, we built a high-efficiency one-dimensional match model centrifugal compressor for first, which was based on cell supply system optimal trim factor. And then variable map width enhancement slot design adjusted by closed ring first introduced to extend surge...

The exhaust pulse energy of engine is capable driving the asymmetric twin-scroll turbine to run complicatedly in a wider flow range, which significantly causes more difficulty an match diesel engine. In present study, It was initially analyzed that with balance valve. First, pulsating model built decouple operation states small and large scroll turbines. Second, experiments were performed on test rig performance stand determine rules parameter, efficiency, blade speed ratio, as well...

Asymmetry, as the most significant characteristic of asymmetric twin-scroll turbines, has a effect on flow characteristics turbines. In this paper, asymmetry parameters, efficiency, pressure ratio ( SPR), single admission parameters SSMR) and divide wall turbines were investigated for first time. First, several with same total critical section twin scrolls different asymmetries designed, well heights wall. Subsequently, these tested studied turbine performance rig. Asymmetry had little...

<div>The two-branch exhaust of an asymmetric twin-scroll turbocharged engine are asymmetrically and periodically complicated, which has great impact on turbine matching. In this article, a matching effect speed parameter turbines based the pulse energy weight distribution heavy-duty diesel was introduced. First, it built as distribution. Then, by comparing average point points corresponding performance map, is revealed that significant deviation from under peak efficiency, leads to...

<div>Asymmetric twin-scroll turbocharging technology, as one of the effective technologies for balancing fuel economy and nitrogen oxide emissions, has been widely studied in past decade. In response to ever-increasing demands improved efficiency reduced exhaust extensive research efforts have dedicated investigating various aspects this technology. Researchers conducted both experimental simulation studies delve into intricate flow mechanism asymmetric turbines. Furthermore,...

<div>The shape and energy distribution characteristics of exhaust pulse an asymmetric twin-scroll turbocharged engine have a significant impact on the matching between turbines engines, as well twin scrolls turbine wheels. In this article, was studied. Experiments were conducted test rig performance stand to determine operation rules strength, flow parameters, isentropic energy, efficiency. The results showed that strength at inlets both small large continuously decreased with increase...