Pipe flow bend forces

Water is flowing at 5 m/s in a 50 mm diameter pipe which incorporates a 90° bend, as shown in Figure 2.8. What is the additional force to which a retaining bracket will be subjected, as a result of the momentum changes in the liquid, if it is arranged symmetrically in the pipe bend ... 

Design of vessel and vent line pipe supports is very important because very large forces can be encountered as soon as venting begins. Figure 4 shows the equations and nomenclature to calculate forces on pipe bends. The authors have heard of situations where vent line bends have been straightened, lines broken off, or vent catch tanks knocked off their foundations by excessive forces. For bends, the transient effects of the initial shock wave, the transition from vapor flow to two-phase flow, and steady state conditions should be considered. Transient conditions, however, are likely to be so rapid as to not have enough dura-... 

Water flows through a 30° pipe bend at a rate of 200 gpm. The diameter of the entrance to the bend is 2.5 in., and that of the exit is 3 in. The pressure in the pipe is 30 psig, and the pressure drop in the bend is negligible. What is the total force (magnitude and direction) exerted by the fluid on the pipe bend ... 

Water is flowing through a 45° pipe bend at a rate of 200 gpm and exits into the atmosphere. The inlet to the bend is 1 in. inside diameter, and the exit is 1 in. in diameter. The friction loss in the bend can be characterized by a loss coefficient of 0.3 (based on the inlet velocity). Calculate the net force (magnitude and direction) transmitted to the flange holding the pipe section in place. 

Without losing generality, in this section we only consider case (3), where the pipe bend is located in the vertical plane with a vertical gas-solid suspension flow at the inlet, as shown in Fig. 11.10. It is assumed that the carried mass and the Basset force are neglected. In addition, the particles slide along the outer surface of the bend by centrifugal force and by the inertia effect of particles. The rebounding effect due to particle collisions with the wall is neglected. 

Bends in the pipes may produce significantly greater head loss than the straight pipes. This type of loss results from the boundary separation and the swirling secondary flow. The boundary separation happens near the inside of the bend. The swirling secondary flow occurs due to the imbalance of centripetal forces as a result of the curvature of the pipe centreline, and this results in energy losses. The loss coefficient (KL) is mainly dependent on the ratio of R/D as shown in Figure... 

The pipe bend in Fig, 7.20 is attached to the rest of the piping system by two flexible hoses which transmit no forces. The fluid enters in the x direction and leaves in the -y direction. The flow rate is 5001bm/s, and the inlet and outlet velocities are each 100 ft/s. The cross-sectional areas at points 1 and 2 are both 0.5 ft. The pressure at point 1 is 50 psig and at point 2 is 40 psig. Calculate and Fy, the X and y components, respectively, of the force in the pipe support. 

The volumetric flow rate of the liquid and the pressure pj point 2 are known as are the pipe diameters at both ends. Derive the equations to calculate the forces on the bend. Assume that the density p is constant. 

Evaluating the forces applied by a flow on the solid walls that surround the fluid. A classical example is the flow in a bend (see Exercise 1). Section 2.5 deals with the equally classical relation between regular head loss and wall friction for the flow inside a straight pipe. In both cases, the pressure changes between the different throughflow surfaces in the domain are known. 

A circular cylindrical pipe whose diameter is 50 cm goes through a 90° bend. If the water flow rate in the pipe is 1 m s , calculate the force applied by the flow onto the support (orientation and magnitude). The absolute pressure measured at the inlet of the bend is 2 bar and the air surrounding the pipe is assumed to be at a pressure of 1 bar. 

Example 7-2 Consider the details of the forces imparted to a bend as a gas-solid flow passes through it. The surface force on the pipe wall in the x direction can be written as... 

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