Variable hole size nozzle and spray angle fuel injector and MHBIB

1. A fuel injector, comprising:

a nozzle body having a proximal end and a distal end;

an upper row of nozzle holes at least a plurality of which being equally spaced about a first circumference of the nozzle body, and the nozzle holes of the upper row have one or more diameters; and

a lower row of nozzle holes located between the distal end and the upper row of nozzle holes, and each of the nozzle holes in the lower row has a diameter less than the one or more diameters of the nozzle holes of the upper row;

wherein the upper row has a first number of holes that is greater than a second number of holes in the lower row; and

wherein one of the first number of holes and the second number of holes is odd.

2. The fuel injector of claim 1 , wherein the nozzle holes of the upper row each have a first diameter and the nozzle holes of the lower row each have a second diameter, the first diameter has a ratio to the second diameter in the range of 3.2:1 to 1.5:1.

3. The fuel injector of claim 1 , wherein the nozzle holes of the upper row each have a first angle relative to a horizontal axis of the nozzle body and the nozzle holes of the lower row each have a second angle relative to the horizontal axis, the first angle having a ratio to the second angle in the range of 0.5:1 to 1.5:1.

4. The fuel injector of claim 1 , wherein the nozzle holes of the upper row are configured to provide a plume of fuel that corresponds to a shape of a piston bowl.

5. The fuel injector of claim 1 , further including a nozzle hole at a bottom center of the nozzle body with a third diameter equal to one of the first diameter or the second diameter.

6. The fuel injector of claim 1 , wherein each nozzle hole includes an inlet having an inlet diameter, an outlet having an outlet diameter, and a passage extending between the inlet and the outlet through the nozzle body, the inlet diameter being different from the outlet diameter.

7. A method, comprising;

injecting a plume of fuel into a combustion chamber toward an outer bowl of a piston; and

impinging the plume of fuel onto an inlet lip formed between the outer bowl and an inner bowl of the piston;

wherein the inlet lip redirects the fuel upon impact to provide turbulence and additional fuel-air mixing in a central region of the piston; and

wherein the outer piston bowl is configured to redirect injected fuel radially inward and upwards towards a piston crown.

8. A method, comprising;

operating a fuel injector in response to a low engine load condition such that a first fuel injection event occurs in which the fuel is injected into a combustion chamber from a nozzle of the injector having a plurality of holes arranged in a lower row and an upper row, the first fuel injection event injecting at least a portion of fuel from the lower row; and

operating the fuel injector in response to a high engine load condition such that a second fuel injection event occurs in which fuel is injected from the lower row and from the upper row;

wherein the fuel injected in the first fuel injection event maintains a predetermined air-fuel ratio in a central region of a piston; and

wherein operating the fuel injector in response to a low engine load condition includes directing the fuel through the lower row at a first angle relative to a plane containing a top surface of the piston, and operating the fuel injector in response to a high engine load condition includes directing the fuel through the upper row at a second angle relative to the plane, the first angle being larger than the second angle.