What's the reason for the J-15D having a different radome than the other ones?
Sharp eyes.
Random is a housing for radar, so probably a different radar from those of J15/J15T. @Tam any comment?
I thought that was fairly well established/well known.
In the image that iBBz is referring to, there is one J-15D and two J-15Ts.
Baseline J-15, J-15D, and J-15T all have different radome geometries from one another.
Similarly, J-16D and J-16 also have different radome geometries.
Different radar setups for them is not a surprise given their differing roles; in the case of EA-18G and F-18E/F Block II onwards, they have the same radome geometry because they use the same radars, but that isn't thought to be the case for J-16D and J-16, or J-15D versus J-15 and J-15T.
It isn't that J-15D is different to "J-15/J-15T" in terms of radome geometry or radar setup, but more that J-15D, J-15D and J-15T all have different radome geometries and thus likely radars, form one another.