I've searched a lot about this, but couldn't find it. I want to know who's the orc (Uruk-Hai) leader from Battle of Helm's Deep who had no helmet (just armor), climbed on the rock and roared very loud.
His name has never been revealed.
As E.J. points out in a comment on the question, in the book there are no identifiable commanders:
It was now past midnight. The sky was utterly dark, and the stillness of the heavy air foreboded storm. Suddenly the clouds were seared by a blinding flash. Branched lightning smote down upon the eastward hills. For a staring moment the watchers on the walls saw all the space between them and the Dike lit with white light: it was boiling and crawling with black shapes. some squat and broad, some tall and grim, with high helms and sable shields. Hundreds and hundreds more were pouring over the Dike and through the breach. The dark tide flowed up to the walls from cliff to cliff. Thunder rolled in the valley. Rain came lashing down.
Arrows thick as the rain came whistling over the battlements, and fell clinking and glancing on the stones. Some found a mark. The assault on Helm's Deep had begun, but no sound or challenge was heard within; no answering arrows came.
The assailing hosts halted, foiled by the silent menace of rock and wall. Ever and again the lightning tore aside the darkness. Then the Orcs screamed, waving spear and sword, and shooting a cloud of arrows at any that stood revealed upon the battlements; and the men of the Mark amazed looked out, as it seemed to them, upon a great field of dark corn, tossed by a tempest of war, and every ear glinted with barbed light.
The Two Towers Book 3 Chapter 7: "Helm's Deep"
But this original character is unnamed in the movie, as well. According to the script (PDF link), he's just "Uruk-hai Commander":
ANGLE ON: The URUK-HAI COMMANDER roars at his troops. They stop their march.
WIDE ON: The two armies stand still opposite each other...each waiting for the other.
ANGLE ON: ARAGORN moves to the edge of the BATTLEMENT.
ANGLE ON: The URUK-HAI stand impatiently, waiting for their orders.
ANGLE ON: GIMLI jumps and strains to see.
GIMLI: What's happening out there?
LEGOLAS: Shall I describe it to you?
He looks at GIMLI with a grin.
LEGOLAS (CONT'D): Or would you like me to fetch you a box?
WIDE ON: The URUK-HAI COMMANDER roars. The ENTIRE URUK-HAI ARMY begins POUNDS their spears on the ground.
The Two Towers (2002)
The French Tolkien Wikia says his name was Mog