Reducing the idle speed of a gasoline rotary engine with hydrogen addition

- We studied the performance of a H2-gasoline rotary engine at reduced idle speeds.
- The CoVn and Ef decreased after the H2 blending.
- Both CA0-10 and CA10-90 were shortened by the H2 addition.
- Tmax increased due to the H2 enrichment.
- H2 addition resulted in the reduced HC, CO and CO2 emissions.

This paper presented an experimental study about the idle performance of a rotary engine fueled with hydrogen and gasoline blends. The idle speed was reduced from original 2400 to 2300 and 2200 rpm, and hydrogen energy percentage (βH2) was varied from 0% to 35.0%. Test results showed that cyclic variation was raised with the decrease of idle speed whereas reduced with the increase of βH2. Both decreasing idle speed and increasing βH2 were effective on reducing engine fuel consumption. Total fuel energy flow rate was effectively dropped from 22.4 MJ/h under “2400 rpm and βH2 = 0%” to 20.01 MJ/h under “2200 rpm and βH2 = 35.0%”. Combustion duration was reduced through increasing βH2. HC and CO emissions were dropped with the increase of βH2, but increased after reducing idle speed. CO2 emission was decreased after reducing idle speed and adding hydrogen.