Two aspects have been researched in this project. The first is that the perforating parameters ranges were enlarged, shot depth is 50mm-500mm, diameter is 5mm-50mm, shot density is 1-40 hole/m, angular phase is 30°, 45°, 60°, 90°, 120°, 180°, 360°.
In this paper, rock fracturing mechanism and functioning processes of six respects are described, such as : the formation of perforating hole, perforating hole fracturing and expansion, rock slit linked up, supporting and stop splitting.
The field test proved that the technologies of increasing gun perforation efficiency, optimizing injection-production parameters, plugin huff and puff and the casing pipe protection have improved the development infection, and make a base of mew wells location of vertical wells or horizontal wells, and make a good sense to develop oil reservoir in high efficiency.
It is shown that perforation as a hydraulic factor can improve significantly the parameters of the sonic ejector in the critical regime.
Induction of subsonic wind tunnels with slight perforation
The plane limiting boundary problem on the subsonic flow over a dipole is solved in elementary functions for the case of small velocity perturbations at the stream boundary and a low perforation factor.
The solution obtained, while not coinciding with the solution for the case of unperforated walls everywhere when the perforation factor equals zero, gives a simple rule for allowing for induction.
From the solution obtained, the optimum degree of perforation of the wall is found for which distortion of the pressure coefficient on the surface of the model is a minimum in comparison with the unbounded flow round the body.