空投MK46-Ⅴ型鱼雷作战能力

以鱼雷声自导装置探潜原理为基础,分析了MK46-V型鱼雷在使用低速制后声自导性能的变化,并对其反潜作战能力进行了仿真计算.

Inverse speed analysis and low speed control of underwater vehicle

Inverse speed is a reversible maneuver.It is a characteristic of underwater vehicle at low speed.Maneuverability in the vertical plane at a speed lower than inverse speed is different from one at higher speed.In the process of underwater working for observation,AUV's cruise speed is always low.Therefore,the research on inverse speed is important to AUV's maneuverability.The mechanism of inverse speed was analyzed,and then the steady pitching equation was derived.The parameter expression of track angle in vertical plane was deduced.Furthermore,the formula to calculate the inverse speed was obtained.The typical inverse speed phenomenon of the flat body and the revolving body was analyzed.Then the conclusion depicts that,for a particular AUV with flat body,its inverse speed is lower than that of revolving body.After all the calculation and the analysis,a series of special experiments of inverse speed were carried out in the simulation program,in the tank and in the sea trial.

Study on Low-Temperature Traction Behavior of a Space Lubricating Oil No.4116

The traction behavior of space lubricating oil No. 4116 was measured and analyzed at various oil inlet temperatures below 0 ℃ and various rolling speeds under normal loads by a test rig simulating the operating conditions of space bearings. A traction coefficient calculation model was presented. The rheological property and rheological parameters of the lubricant at a low oil inlet temperature were analyzed based on the Tevaarwerk-Johnson model. The results showed that the lubricating oil No. 4116 was sensitive to the rolling speed and had lower sensitivity to the normal load. This lubricating oil is more suitable for applications under high speed when it is used below 0 ℃. It behaves as an elastic-plastic fluid operating below 0 ℃. Both the average limiting shear stress and the average elastic shear modulus have a negative correlation with the rolling speed and oil inlet temperature and have a positive correlation with the normal load.

Discussion of the target-missile control scheme with supersonic speed at minimum altitude

An antiship missile with supersonic speed at minimum altitude is an effective weapon to break through a defense line. The former Soviet Union was a leader in this field since it had developed several kinds of antiship missiles which obtained supersonic speed at minimum altitudes. To counter this kind of missile, many countries have been developing corresponding antimissiles. For the purpose of verifing the antimissile missile′s effectiveness in intercepting antiship missiles, a target-missile is needed. A target-missle is cheaper and can imitate the main characteristics of antiship missiles with supersonic speed at minimum altitude. In this paper, the control scheme of a target missile flying with supersonic speed at minimum altitude is studied. To counter the problem of hedgehopping over the sea, a control scheme utilizing a SINS+altimeter was proposed. In this scheme, both the quick response ability of altitude control and the anti-jamming problem were considered. A simulation experiment shows that when an integrated altitude control system is used, the anti-disturbance ability of the integrated altitude is good and the response speed of altitude control system can be dramatically improved.

Experimental Investigations of Micro Air Injection to Control Rotating Stall

Steady discrete micro air injection at the tip region in front of the first compressor rotor has been proved to be an effective method to delay the inception of rotating stall in a low speed axial compressor. Considering the practical application a new type of micro injector was designed and described in this paper, which was imbedded in the casing and could be moved along the chord. In order to verify its feasibility to other cases, such as high subsonic axial compressor or centrifugal compressor, some other cases have been studied. Experimental results of the same low speed axial compressor showed that the new injector could possess many other advantages besides successfully stabilizing the compressor. Experiments performed on a high subsonic axial compressor confirmed the effectiveness of micro air injection when the relative velocity at the blade tip is high subsonic. Meanwhile in order to explore its feasibility in centrifugal compressor, a similar micro injector was designed and tested on a low speed centrifugal compressor with vaned diffuser. The injected mass flow was a bit larger than that used in axial compressors and the results showed micro injection could also delay the onset of rotating stall in the centrifugal compressor.