Abstract
The energy loss in a pipe fitting with a branching angle of 135 degrees was studied in turbulent flow. To reduce the energy loss, the shape of the pipe fitting with different rounding and chamfering sizes at the up- and downstream edges of the lateral entrance were chosen similar to the branching angles of 90 and 45 degrees. The energy loss coefficients for the flow from the main conduit into the lateral conduit and the straight-through flow and also the power loss coefficient were messured and discussed. As the results, the energy loss becomes smallest when the sizes of rounding and chamfering are the same as those of the width of the lateral conduit similarly to the case of the branching angle of 90 and 45 degrees. The energy loss coefficients for the pipe fitting with rounding are smaller than those with chamfering. The empirical formulae for the energy loss coefficients for the flow from the main conduit into the lateral conduit and the straight-through flow are decided at the above sizes of rounding and chamfering, as expressed by equations (4) to (7). Moreover, the total empirical formulae for the energy loss coefficients for the flow from the main conduit into the lateral conduit and for the straightthrough flow are decided at the above sizes of rounding and chamfering, as expressed by equations (8) to (11).
