On comparing the models, there is difference between the two (especially when it comes to network). I suggest that you do have a look at this before proceeding and try that first.
But if you are sure that your model is N5100 and still want to try and proceed, there is a workaround you can do so it doesn't check/compare the models.
Open the ROM zip file with winrar.
META-INF/com/google/android and open the
updater-script with notepad.
You are looking for line similar to:
getprop("ro.product.device") == "N5100" || abort("This package is for \" N5100\" devices; this is a \"" + getprop("ro.product.device") + "\".");
(this line should in fact be the very first line in script).
Erase this line, save the zip and flash again. It won't verify your model.
Warning: I am not really a Samsung user. So I am not aware of its models and naming conventions that much. Make sure about models otherwise you may end up bootlooping your device or having other problems and having to flash firmwares over again (you can ask on xda itself about this).
Hope this helps ;)