Methods and systems for multi-fuel engine startup

An engine system for a vehicle, comprising:

• an engine configured to combust more than one type of fuel;
• an alternator/generator mechanically coupled to the engine;
• a first fuel storage reservoir coupled to the engine and configured to deliver a first fuel to the engine for combustion;
• a second fuel storage reservoir coupled to the engine and configured to deliver a second fuel to the engine for combustion;
• and
• a controller configured with executable instructions stored on non-transitory memory that, when executed, cause the controller to;
• crank the engine using the alternator/generator in response to detection of a cold start request and initiate fuel injection via fuel injectors with a first ratio of the first fuel to the second fuel when an engine speed reaches a first an engine speed threshold;
• adjust the fuel injection to a second ratio of the first fuel to the second fuel when the engine speed reaches an idling speed, the second ratio lower than the first ratio;
• and
• adjust the fuel injection to a third ratio of the first fuel to the second fuel when operation of the engine at part-load is requested, the third ratio higher than the second ratio and lower than the first ratio.

A method for a cold engine start, comprising:

• cranking an engine using a starting device;
• injecting hydrogen and diesel at the engine at a first hydrogen to diesel injection ratio in response to engine speed reaching a first threshold, and deactivating the starting device;
• decreasing injection of hydrogen to a second hydrogen to diesel injection ratio in response to an engine parameter reaching a second threshold;
• increasing injection of hydrogen to a third hydrogen to diesel injection ratio in response to a request for engine operation at part-load;
• and
• wherein injecting hydrogen and diesel at the high hydrogen to diesel injection ratio includes decreasing emission of unburned diesel during the cold engine start.