Systems, apparatus, and methods for inducing enhanced radical ignition in internal combustion engines using a radical chemicals generator

Abstract

Systems, devices, and methods described herein provide one or more radical chemicals generators (RCGs) and/or mini-chambers (M-Cs) that can be used to provide enhanced radical ignition (ERI) in an internal combustion engine. RCGs as described herein can include quenching systems (QSs) that can be configured to quench a flame of combustion products to produce a jet of partial combustion products containing radical species (RS). The jet of partial combustion products can be injected to a main combustion chamber (MCC) of an engine to induce ERI. ERI can proceed under leaner fuel conditions and lower temperatures compared to those needed for conventional thermally induced, fuel oxidation chain initiation reaction processes.

1 . An apparatus, comprising:
 a housing defining a radical chemicals generator volume (RCGv);   a fuel delivery control device coupled to a passageway extending into the RCGv, the fuel delivery control device configured to control delivery of a portion of fuel into the RCGv via the passageway;   an ignition device configured to ignite a mixture of air and the portion of fuel in the RCGv to generate a flame that produces combustion intermediates and combustion products; and   a quenching system (QS) being coupled to a head of the engine such that the QS is offset from a centerline of the engine, the QS including a plurality of orifices configured to:
 quench the flame to produce jets of partial combustion products containing radical species (RS); and 
 inject the jets of partial combustion products into a main combustion chamber (MCC) of an engine containing a fuel-air charge to induce ignition of the fuel-air charge, 
   each orifice of the plurality of orifices having:
 a section that extends along a longitudinal axis of the quenching system; and 
 an end opening into the MCC that is angled relative to the longitudinal axis of the QS toward the centerline of the engine, such that the jet of partial combustion products exiting that orifice can penetrate across the MCC when injected into the MCC. 
   
     
     
         2 . The apparatus of  claim 1 , wherein the ends opening into the MCC of the plurality of orifices are angled relative to the longitudinal axis of the QS by an angle of between about 20 degrees and about 40 degrees. 
     
     
         3 . The apparatus of  claim 1 , wherein the end opening into the MCC of a first orifice from the plurality of orifices is angled relative to the end opening into the MCC of a second orifice from the plurality of orifices, such that the first and second orifices are configured to inject first and second jets of partial combustion products into the MCC that are set apart from one another by a separation angle. 
     
     
         4 . The apparatus of  claim 3 , wherein the separation angle is between about 20 and about 70 degrees. 
     
     
         5 . The apparatus of  claim 1 , wherein each orifice from the plurality of orifices has a length-to-diameter ratio of greater than about 5. 
     
     
         6 . The apparatus of  claim 1 , wherein the housing further includes a coolant jacket configured to cool the RCGv. 
     
     
         7 . The apparatus of  claim 1 , wherein the housing further includes a threaded surface configured to attach to a threaded opening in the head of the engine. 
     
     
         8 . The apparatus of  claim 1 , further comprising a sleeve configured to fit within an opening in the head of the engine and to attach to the head of the engine, the sleeve defining an opening for receiving the housing. 
     
     
         9 . The apparatus of  claim 1 , wherein the RS include at least one of: a hydroxyl radical (OH), a hydroperoxyl radical or perhydroxyl radical (HO2), formaldehyde (CH2O), hydrogen peroxide (H2O2), methyl radical (CH3), methylidyne radical (CH), monotomic oxygen radical (O), or monotomic hydrogen radical (H). 
     
     
         10 . The apparatus of  claim 1 , wherein the spark device includes at least one of a spark plug, a laser ignition system, a plasma ignition system, or a pilot ignition system. 
     
     
         11 . An apparatus, comprising:
 a housing defining a radical chemicals generator volume (RCGv);   a fuel delivery control device coupled to a passageway extending into the RCGv, the fuel delivery control device configured to control delivery of a portion of fuel into the RCGv via the passageway;   a spark device configured to ignite a mixture of air and the portion of fuel in the RCGv to generate a flame that produces combustion intermediates and combustion products; and   a quenching system (QS) including a plurality of orifices, the plurality of orifices having a predetermined length-to-diameter ratio of at least about five such that the plurality of orifices is configured to quench the flame to produce a jet of partial combustion products containing radical species (RS),   the plurality of orifices further configured to inject the jet of partial combustion products into a main combustion chamber (MCC) of an engine containing a fuel-air charge to induce ignition of the fuel-air charge.   
     
     
         12 . The apparatus of  claim 11 , wherein the predetermined length-to-diameter ratio of the plurality of orifices is at least about ten. 
     
     
         13 . The apparatus of  claim 11 , wherein each orifice from the plurality of orifices has a circular cross-sectional area with a cross-sectional diameter of between about 0.5 mm and about 5 mm. 
     
     
         14 . The apparatus of  claim 11 , wherein each orifice from the plurality of orifices has a length of at least about 10 mm. 
     
     
         15 . The apparatus of  claim 11 , wherein the housing is configured to attach to the engine such that a longitudinal axis of the QS is angled relative to a centerline of the engine. 
     
     
         16 . The apparatus of  claim 15 , wherein each orifice from the plurality of orifices has an end opening into the MCC that is angled with respect to the longitudinal axis of the QS. 
     
     
         17 . An apparatus, comprising:
 a housing defining a radical chemicals generator volume (RCGv);   a fuel delivery control device coupled to a passageway extending into the RCGv, the fuel delivery control device configured to control delivery of a portion of fuel into the RCGv via the passageway;   a spark device configured to ignite a mixture of air and the portion of fuel in the RCGv to generate a flame that produces combustion intermediates and combustion products; and   a quenching system (QS) including a plurality of orifice sets, each orifice set from the plurality of orifice sets including:
 a plurality of sub-orifices configured to quench the flame to produce partial combustion products containing radial species (RS); and 
 an exit orifice configured to inject a jet of the partial combustion products produced by each of the plurality of sub-orifices into a main combustion chamber (MCC) of an engine containing a fuel-air charge to induce ignition of the fuel-air charge, 
 each of the plurality of sub-orifices having (1) a first end that opens into the RCGv and is spaced from that of the remaining sub-orifices of the plurality of sub-orifices and (2) a second end that merges together with that of the remaining sub-orifices of the plurality of sub-orifices to form the exit orifice. 
   
     
     
         18 . The apparatus of  claim 17 , wherein the exit orifice has an end that opens into the MCC with a cross-sectional area that is equal to a sum of the cross-sectional areas of the plurality of sub-orifices. 
     
     
         19 . The apparatus of  claim 17 , wherein the exit orifice of each orifice set from the plurality of orifice sets has a first end where the plurality of sub-orifices merge together and a second end that opens into the MCC, with the first end having a greater cross-sectional area than the second end. 
     
     
         20 . The apparatus of  claim 19 , wherein the exit orifice of each orifice set from the plurality of orifice sets has a cross-sectional area that decreases from the first end of the exit orifice to the second end of the exit orifice. 
     
     
         21 . The apparatus of  claim 17 , wherein the exit orifice of each orifice set from the plurality of orifice sets has an end opening into the MCC that is angled relative to a longitudinal axis of the QS. 
     
     
         22 . The apparatus of  claim 17 , wherein the exit orifice of a first orifice set from the plurality of orifice sets opens into the MCC at a predetermined angle relative to the exit orifice of a second orifice set from the plurality of orifice sets, the predetermined angle being between about 20 and about 70 degrees. 
     
     
         23 . The apparatus of  claim 17 , wherein the second end of each sub-orifice from the plurality of sub-orifices of each orifice set from the plurality of orifice sets has a non-circular cross-section. 
     
     
         24 . The apparatus of  claim 17 , further comprising a sleeve configured to fit within an opening in a head of the engine and to attach to the head of the engine, the sleeve defining an opening for receiving the housing. 
     
     
         25 . An apparatus, comprising:
 an engine including:
 a head defining a plurality of openings that open into a main combustion chamber (MCC); 
 a cylinder coupled to the head and defining a channel; and 
 a piston disposable within the channel and configured to reciprocate along a length of the channel during a plurality of combustion cycles, the piston including a crown that forms a seal against an inner surface of the cylinder, 
 the head, the cylinder, and the crown collectively defining the MCC; and 
   a plurality of radical chemical generators (RCGs), each RCG from the plurality of RCGs configured to couple to a different opening of the plurality of openings, each RCG from the plurality of RCGs including:
 a housing defining a radical chemicals generator volume (RCGv); 
 a fuel delivery control device configured to control delivery of fuel into the RCGv; 
 a spark device configured to ignite a mixture of air and fuel in the RCGv to generate a flame that produces combustion intermediates and combustion products; and 
 a quenching system (QS) configured to quench the flame to produce jets of partial combustion products that can be injected into the MCC of the engine. 
   
     
     
         26 . The apparatus of  claim 25 , wherein the QS of each RCG from the plurality of RCGs is further configured to inject the jets of partial combustion products into the MCC of the engine at the same time to induce ignition of a fuel-air charge in the MCC. 
     
     
         27 . The apparatus of  claim 26 , wherein the jets of partial combustion products are angled or offset from one another to avoid overlapping with one another and to increase volumetric distribution of RS within the MCC. 
     
     
         28 . The apparatus of  claim 25 , wherein the QS of a first RCG from the plurality of RCGs is configured to inject a first set of jets of partial combustion products into the MCC before the QS of a second RCG from the plurality of RCGs injects a second set of partial combustion products into the MCC. 
     
     
         29 . The apparatus of  claim 28 , wherein the QS of the first RCG is configured to inject the first set of jets of partial combustion products into the MCC to increase a quantity of RS in the MCC, and the QS of the second RCG is configured to inject the second set of jets of partial combustion products into the MCC to induce ignition of a fuel-air charge in the MCC. 
     
     
         30 . The apparatus of  claim 25 , further comprising a plurality of mini-chambers (M-Cs) configured to:
 receive a portion of gases from the MCC during a combustion event or a compression phase of a first combustion cycle from the plurality of combustion cycles;   allow generation and storage of RS in the portion of gases; and   release the portion of gases including the generated RS into the MCC during a second combustion cycle from the plurality of combustion cycles immediately subsequent to the first combustion cycle.