Vacuum system

1. A vacuum system, comprising:

a toolbar;

a row unit bracket configured to individually couple a respective row unit to the toolbar;

a fan coupled to the toolbar and configured to draw air through a metering system of the respective row unit; and

an exhaust duct extending through the row unit bracket, wherein the exhaust duct is coupled to the fan and configured to discharge airflow from the fan toward a ground.

2. The system of claim 1 , wherein the exhaust duct comprises a front wall, a rear wall, a first sidewall, and a second sidewall.

3. The system of claim 2 , wherein the front wall, the rear wall, the first sidewall, and the second sidewall extend from a first end of the exhaust duct to a second end of the exhaust duct.

4. The system of claim 2 , wherein the first sidewall comprises a first curved portion and a first straight portion and the second sidewall comprises a second curved portion and a second straight portion.

5. The system of claim 4 , wherein the first curved portion is longer than the second curved portion.

6. The system of claim 2 , wherein the exhaust duct defines an inlet and an outlet, wherein a first area of the inlet is greater than a second area of the outlet.

7. The system of claim 6 , wherein the inlet is angled with respect to a central longitudinal axis of the exhaust duct.

8. The system of claim 6 , wherein the front wall or the rear wall comprises a boss configured to couple to the planter frame or the row unit bracket.

9. A vacuum system, comprising:

a row unit bracket configured to individually couple a respective row unit to a toolbar; and

an exhaust duct extending through the row unit bracket, wherein the exhaust duct is configured to couple to a fan configured to draw air through a metering system of the respective row unit, and the exhaust duct is configured to discharge airflow from the fan toward a ground.

10. The system of claim 9 , wherein the exhaust duct comprises a front wall, a rear wall, a first sidewall, and a second sidewall.

11. The system of claim 10 , wherein the rear wall and the front wall define different lengths.

12. The system of claim 10 , wherein a first width of the first sidewall and a second width of the second sidewall change from an inlet of the exhaust duct to an outlet of the exhaust duct.

13. The system of claim 10 , wherein the first sidewall comprises a first curved portion and a first straight portion and the second sidewall comprises a second curved portion and a second straight portion.

14. The system of claim 13 , wherein the second curved portion is longer than the first curved portion.

15. The system of claim 10 , wherein the front wall curves between the first sidewall and the second sidewall.

16. The system of claim 10 , wherein a first end of the exhaust duct is angled with respect to a second end of the exhaust duct.

17. The system of claim 10 , wherein the rear wall comprises a boss configured to couple to the planter frame or the row unit bracket.

18. A vacuum system, comprising:

an exhaust duct extending through a row unit bracket, wherein the exhaust duct is configured to couple to a fan configured to draw air through a metering system of a respective row unit, the exhaust duct is configured to discharge airflow from the fan toward a ground, the row unit bracket is configured to individually couple the respective row unit to a toolbar, and the exhaust duct comprises:

a front wall;

a rear wall;

a first sidewall comprising a first curved portion and a first straight portion; and

a second sidewall comprising a second curved portion and a second straight portion.

19. The system of claim 18 , wherein the first curved portion is longer than the second curved portion.

20. The system of claim 18 , wherein the exhaust duct defines an inlet and an outlet, wherein a first area of the inlet is greater than a second area of the outlet.