Please read the detail article from link
The Dragon's New Claws: The J-10B Emerging
The J-10B appears as the next iteration of China's vaunted 4th Generation fighter and looks to take the J-10 to the
4.5 Generation level.
The differences that have been identified from the earlier J-10 include a DSI intake, similar to the one on the FC-1/JF-17. The nose is now oval, more similar to an F-16's and is slightly canted downwards. An IRST similar to the J-11Bs also feature on top of the nose. Slanted radome paint along with some of the other features suggest an
AESA radar.
http://1.bp.blogspot.com/_lHjnoEO3vOM/SfNDhsWNRbI/AAAAAAAAAMg/mzEFtVnHzLI/s400/j10b+f16+comparison+deino.jpg
A retractable refueling probe is likely, given the development of the J-10 thus far, and is possibly located on the port side, not visible in the latest photographs. The photographs also suggest new under-wing pylons. These appear to be strengthened for a variety of possible uses, ranging from larger drop tanks to ASMs.
The engine is likely to be either a redesigned WS-10A (B?) or possibly the WS-15, a new generation engine currently in advanced development. This would not only have higher thrust than the AL-31s, but also feature TVCs, giving the J-10Bs vaunted agility an even greater boost. The actual engine on the aircraft presently on the released pictures, is the AL-31.
The Pakistan Air Force (PAF) has shown a great deal of interest in the J-10 project as a possible substitute for Western combat aircraft for its high end requirements. The PAF, however, wanted a more modern version. Just as the FC-1s (and before the FC-1, the F-7s) were significantly upgraded due to the PAF's push for improvements, the J-10 appears to be going through a similar phase. The reason for this is that the PAF has a far closer view of Western technologies and trends and thus can provide deeper insight than more insulated Chinese expertise. The J-10B in all likelihood has had major input from the PAF and is the FC-20 that the PAF has ordered.
According to well informed sources, the aforementioned delay is primarily as a result of engine issues. The AL-31 would create maintenance and logistics problems for the PAF, given the lack of a working relationship with Russia. The WS-10A/B has not met quality standards. This leaves the PAF high and dry for now vis-a-vis the J-10. Their engine options now are to either to wait for a more reliable WS-10A version or to go for the WS-15, a new generation engine with similar dimensions.
The delay in procurement is critical for PAF as it needs a quality high end to counter the larger IAF with her MKIs, Mirage-2000s and MRCA. With a new sensor rich environment dominated by AWACS on both sides and a large number of BVR platforms, higher altitude BVR engagements would become vital
J-10s are ideally suited for such combat given their aerodynamics including low wing loading in an A2A configuration. The instantaneous turn rates achievable on the J-10 (or the Euro canards) are likely to give an advantage in such engagements, as opposed to the high wing loadings on the over-evolved F-16s which were essentially designed for turning dog fights rather than high altitude BVR slash and dash maneuvers.
With the AESA equipped new J-10Bs, higher thrust engines and better EW/Avionics, PAF would reclaim the qualitative edge over the IAF. These J-10s would be superior in air combat than anything that the IAF fields today and would only be matched by a possible MRCA acquisition by India. Even then, with the 5 present contenders left in the MRCA, only the Eurofighter (assuming AESA radars) would be able to match the J-10 in air-to-air combat.
The PAF is looking for a total of 150 high end aircraft like the F-16 Block 52s and the FC-20 (J-10Bs or J-10Ps). The FC-20s could be procured in greater numbers, depending on relations with the U.S. and the operability of the F-16s. The J-10Ps and the JF-17s make a perfect pair - one ideal for high altitude air superiority and deep strike missions while the other ideal as a true multirole fighter. Where the J-10 lacks in deep strike, the F-16s make up for it. Where the J-10s lack in CAS, the JF-17s make up for it. Where the JF-17 lacks in high altitude BVR engagements, the J-10s make up for it.
The J-10s, F-16s and JF-17s also fit into the AFDP-2019 requirements. The AFDP-2019 is the core document on the strategic planning of Pakistan's armed forces over 15 years. While this document is not available in the public domain, informed sources note that the PAF has been assigned procurement of only single engine combat aircraft. The J-10Ps/FC-20s coupled with the JF-17s and F-16s thus ideally meet these requirements.
J-10 Vs F-16 Technical Comparison
The F-16 was designed from the outset as a dog-fighter. The moderate sweep of the wings and aspect ratios were ideal for this. The trade-off however, was greater supersonic resistance. The thrust offered by the two engine options on the F-16 is impressive even to this day. TWR in air combat is about 1.15, ensuring impressive climbing rates and sustained turn rates. As noted, the F-16 sacrificed supersonic performance, not only in its wing design but also in its fixed air intakes. In supersonic flight, engine thrust is lost. While it can reach Mach 2.0, pragmatically it has poor supersonic performance.
While the F-16 sacrificed supersonic performance for subsonic dogfighting, the J-10 did not make the same sacrifice. Thus, while when the F-16 was designed, turning dogfights were what was projected as the bread and butter of air combat, when the J-10 was being designed, the BVR era had arrived (or re-arrived). The J-10s aerodynamic design, including wing design and inlet design, take this into account. For instance, the J-10 visibly has greater wing sweep and a variable inlet. With the J-10B, a DSI intake. While the J-10B sacrifices maximum theoretical top speeds with its DSI intakes, for all relevant combat speeds, it gives the J-10 superior performance.
Under modern BVR conditions and higher altitude combat, the J-10 is significantly superior to the F-16. This is also reflected in its higher instantaneous turn rates. The Mirage-2000s have been a point of major concern both for the Pakistanis and the Turkish air forces, because of these aerodynamic issues, despite the Mirages weak engines. The Greeks, who operated both the Mirage 2000 and F-16C considered the F-16 to be better at low altitude, low speed, hard turning fights, and Mirage 2000 to be superior at hi-hi.The F-16 would have to attempt to survive the first merge in an air combat scenario, which becomes increasingly suicidal with high off-bore sight missiles. BVR further compounds these problems for the F-16s. In previous eras, flying hi and fast was fine, but you often had to come down low to engage a low flying enemy aircraft. Today, that becomes less relevant with longer range BVR missiles and look-down shoot-down capabilities.
The F-16 has also been adding weight over time and attempting to counterbalance this with increased engine thrust. However, since wing area remained the same, maneuverability has been sacrificed. Higher wing loading is particularly detrimental for higher altitude maneuverability. The J-10 on the other hand, has all the wing area it could ever need with a delta canard layout.
The newer block F-16s however, are great for low altitude air-to-ground missions. The high wing loading favors low fliers and the moderate wing sweep helps handling at lower speeds often necessary during ordnance delivery. The J-10 is thus not ideal for the CAS role. However, because of the range and payload advantages, the J-10 can be considered an effective deep striker. CAS was never a pressing need for the PLAAF, and the PAF has the JF-17 which is ideal for that role.