Bell mouth

About: Bell mouth is a research topic. Over the lifetime, 603 publications have been published within this topic receiving 1624 citations.

Parametric Study of Operating Conditions in an Annular Turbine Sector Cascade

Abstract: Linear and Annular cascade test rigs have been widely used for aerodynamic performance and aeromechanical testing of turbine and compressor blades. A sector annular cascade facility AETR was built at KTH for aero elastic turbine blade testing. Despite inherently aperiodic, the facility provides a less complicated and a cost effective way of analyzing blades. The facility consists of a flow settling chamber, a conditioning chamber and a variable annular sector inlet duct to the cascade. Flexible side walls have been built on purpose to ensure sealed guidance of the flow at any arbitrary inflow angle. The flexible side walls not only guide the flow but have a major influence on achieving blade loading periodicity. Therefore the objective of the current work is to study the influence of the side walls configuration on the overall periodicity of the cascade. The work was accomplished in three phases. In the first phase, a parametric model of the whole test rig geometry was created which included the inlet chamber, the bell mouth, inlet /outlet side walls and blade row. The parametric model was required for automatic geometry adaptation for different operating conditions. In the second phase, grid was generated for the whole test rig with special attention to the blade passage, keeping in view various meshing constraints. The requirement was to create a quality structured grid in the passages and tip clearance by keeping the passage mesh periodic. Moreover, high camber of the blade also posed an additional challenge in meeting all the meshing constraints. Phase I and II were accomplished iteratively as certain geometry modifications were needed due to mesh errors caused by geometry translation problems and ease of blocking strategy adopted. In the final phase, a CFD analysis was performed for various operating points and various inlet and outlet wall angles. Phase II and III were also completed iteratively as convergence issues led to consequent improvement of grid. The distinctive feature of the current work was to model, mesh and analyze the test rig as a whole, i.e. it includes inlet chamber, bell mouth and side walls. Majority of the work was dedicated to CAD model and mesh generation. A preliminary CFD analysis performed in phase III gives a partial idea of the test rig performance. Current work can serve as a solid foundation for a more rigorous CFD analysis encompassing wide range of operating points, turbulence and transition models in order to better estimate annular sector cascade performance.

Dust collector pneumatic ground brush

Abstract: The invention discloses a dust collector pneumatic ground brush which comprises a ground brush body and a pipe joint arranged on the ground brush body. The ground brush body comprises an upper cover, a base, a covering board and a lifting plate of which the center is provided with a yielding hole; the outer surface of a bent pipe part at the front end of an elbow is provided with a mounting groove formed by two flanges; a clamping ring with an opening is mounted in the mounting groove; the outer surface of the clamping ring is provided with at least two hooking parts; the pipe joint is provided with mounting holes for enabling the hooking parts to be embedded in; an opening of the bent pipe part is a bell mouth; the diameter of an outer mouth of the bent pipe part is greater than that of a tail mouth of the bent pipe part; an opening of the pipe joint is a bell mouth; the diameter of an outer mouth of the pipe joint is greater than that of a tail mouth of the pipe joint; the diameter of the outer mouth of the bent pipe part is between the diameter of the outer mouth of the pipe joint and the diameter of the tail mouth of the pipe joint. The dust collector pneumatic ground brush not only can clean a carpet, but also can clean the ground; the application range of the ground brush is greatly enlarged; an air inlet can be guaranteed to have a high vacuum degree when a brush strip extends out; dust collection efficiency is improved; a suction force and the dust suction efficiency at the front end of a dust collection port are increased; moreover, a space capable of being used for designing a dust collection passage in the brush body is large.

Bell-shaped device for solving ventilation problem of air-conditioned seats

Abstract: The invention provides a very comfortable and widely-used bell-shaped ventilation device for air-conditioned seats; and automobiles, offices, cafes, schools and the like can be provided with the device. The technical scheme is that an air inlet main pipe (1) is connected with a connection port of an air inlet bell mouth (3) through a connection port of an air inlet branch pipe (2), the connection port of the air inlet bell mouth (3) is provided with the air inlet bell mouth (4) which is fixedly connected with an air returning bell mouth (6) through a bell mouth connecting pipe (5) arranged between the two, the air returning bell mouth (6) is connected with a connection port of an air returning branch pipe (8) through a connection port of an air returning bell mouth (7), and the connection port of the air returning branch pipe (8) is connected with an air returning main pipe (9). By adopting the above structure, the air conditioning effect that is warm in winter and cool in summer for the seats can be achieved, and the ventilation problem of the air-conditioned seats can be well solved. The device is low in cost, beautiful, comfortable, economical, and practical.

Processing equipment for bell mouth copper pipe and processing method

Abstract: The invention discloses processing equipment and processing method for a bell mouth copper pipe. The processing equipment comprises a cabinet body, an operation table and a bell mouth opening device.A storage plate is fixedly welded into the cabinet body. The cabinet body is divided into a hollowed-out area and a storage area through the storage plate. The operation table is welded to the upper end surface of the cabinet body. Second cross rods which are symmetrically distributed are welded to the operation table. Two sliding sleeve blocks are arranged on the two second cross rods. A third cross rod is mounted between the two symmetrically distributed sliding sleeve blocks. A clamping device is mounted on the third cross rod. Stand columns are welded to the upper end surfaces of the sliding sleeve blocks. The first cross rod is fixed between the two stand columns. A sliding groove is formed in the first cross rod. The bell mouth opening device comprises a shell. The shell is slidablyconnected with the first cross rod through a first sliding block in the sliding groove. A flaring head is rotationally mounted on the shell. By the adoption of the processing equipment and the processing method, bell mouth opening can be carried out on the copper pipe quickly, and meanwhile the opening success rate is higher.

Solution saturation thickening device

Abstract: The invention relates to a solution saturation thickening device which comprises a criss-cross structured sprayer nozzle and a criss-cross structured fluid cylinder. The sprayer nozzle with a matching shape is sleeved inside the fluid cylinder. Four free ends of the sprayer nozzle are respectively provided with a bell mouth structure. The tube wall which forms the bell mouth is provided with several dispersion holes penetrating the tube wall. The circumferential edge of the free end of each bell mouth and the inner wall of the fluid cylinder can be sealingly arranged together. The sprayer nozzle is communicated with a charge pipe. The fluid cylinder is communicated with a fluid pipe. The sprayer nozzle with the bell mouth structures is cooperatively used along with the fluid cylinder. Thus, a dispersed object inside the charge pipe can be scattered and dispersed out through a fluid inside the fluid cylinder. The dispersion effect is good, and large-scale agitating-type perturbance will not be generated to other fluids in the dispersion space. Dense arrangement of the dispersion holes is helpful for uniform dispersion. Meanwhile, the criss-cross structured sprayer nozzle can work in dispersion uniformly in four directions such that dispersion is more uniform.