Backside features with intermitted pin fins

1. A heat shield panel for a combustor of a gas turbine engine, comprising:

a panel body having a first surface configured to be oriented toward a combustion zone of the combustor, and a second surface opposite the first surface, the second surface being configured to be oriented toward a combustor liner of the combustor;

one or more attachment mechanisms configured to connect the panel body to the combustor liner;

a plurality of standoff pins surrounding each of the one or more attachment mechanisms, each of the plurality of standoff pins including a flat top opposite the second surface;

a plurality of first pin fins projecting from the second surface of the panel body, wherein each of the plurality of first pin fins has a rounded top opposite the second surface; and

a plurality of second pin fins projecting from the second surface of the panel body, wherein each of the plurality of second pin fins has a flat top opposite the second surface,

wherein the plurality of second pin fins are intermittently spaced amongst the plurality of first pin fins,

wherein the plurality of second pin fins are organized in a uniform distribution across the second surface of the heat shield panel;

wherein at least three of the plurality of second pin fins are organized in a polygon pattern; and

wherein at least one of the plurality of first pin fins is positioned between each of the at least three of the plurality of second pin fins and each other second pin fin of the at least three of the plurality of second pin fins.

2. The heat shield panel of claim 1 , wherein the at least three of the plurality of second pin fins are organized in a triangular pattern.

3. The heat shield panel of claim 1 , wherein at least four of the plurality of second pin fins are organized in a square pattern, wherein the at least four of the plurality of second pin fins comprises the at least three of the plurality of second pin fins.

4. The heat shield panel of claim 1 , wherein at least four of the plurality of second pin fins are organized in a rectangular pattern, wherein the at least four of the plurality of second pin fins comprises the at least three of the plurality of second pin fins.

5. The heat shield panel of claim 1 , wherein at least four of the plurality of second pin fins are organized in a trapezoidal pattern, wherein the at least four of the plurality of second pin fins comprises the at least three of the plurality of second pin fins.

6. The heat shield panel of claim 1 , wherein the flat top of each of the plurality of standoff pins is about parallel to the second surface.

7. The heat shield panel of claim 1 , wherein the heat shield panel is a bulkhead heat shield panel comprising an orifice, and wherein the plurality of second pin fins are organized in the uniform distribution across the second surface of the heat shield panel around the orifice.

8. The heat shield panel of claim 1 , wherein the flat top of each of the plurality of second pin fins is about parallel to the second surface.

9. The heat shield panel of claim 1 , wherein each of the plurality of first pin fins are about equal in height.

10. The heat shield panel of claim 9 , wherein each of the plurality of first pin fins further comprises a diameter, and wherein a ratio of the height to the diameter is about equal to 0.8.

11. The heat shield panel of claim 1 , wherein each of the plurality of first pin fins further comprises a first radius located proximate the second surface and a second radius located proximate the rounded top, and wherein the first radius is different from the second radius.

12. The heat shield panel of claim 11 , wherein the first radius is larger than the second radius.

13. The heat shield panel of claim 1 , wherein each of the plurality of second pin fins further includes a radius about equal to a radius of each of the plurality of first pin fins.

14. The heat shield panel of claim 1 , wherein each of the plurality of second pin fins further includes a radius greater than a radius of each of the plurality of first pin fins.

15. The heat shield panel of claim 1 , further comprising: one or more third pin fins projecting from the second surface of the panel body, wherein each of the one or more third pin fins has a flat top opposite the second surface.

16. The heat shield panel of claim 15 , wherein: each of the one or more third pin fins are located adjacent one of the plurality of second pin fins.

17. A combustor for a gas turbine engine, comprising: a combustor liner defining a combustion volume; and a heat shield panel comprising:

a panel body having a first surface configured to be oriented toward a combustion zone of the combustor, and a second surface opposite the first surface, the second surface being configured to be oriented toward a combustor liner of the combustor;

one or more attachment mechanisms configured to connect the panel body to the combustor liner;

a plurality of standoff pins surrounding each of the one or more attachment mechanisms, each of the plurality of standoff pins including a flat top opposite the second surface;

a plurality of first pin fins projecting from the second surface of the panel body, wherein each of the plurality of first pin fins has a rounded top opposite the second surface; and

a plurality of second pin fins projecting from the second surface of the panel body, wherein each of the plurality of second pin fins has a flat top opposite the second surface,

wherein the plurality of second pin fins are intermittently spaced amongst the plurality of first pin fins,

wherein the plurality of second pin fins are organized in a uniform distribution across the second surface of the heat shield panel;

wherein at least three of the plurality of second pin fins are organized in a polygon pattern; and

wherein at least one of the plurality of first pin fins is positioned between each of the at least three of the plurality of second pin fins and each other second pin fin of the at least three of the plurality of second pin fins.