Abstract: A valve with a calibrated flow orifice insert for use in Heating, Ventilation, and Air Conditioning (“HVAC”) applications so as to provide metered flow through the valve. The insert is used as a flow control device and is inserted into a conventional threaded ball valve. The insert has a cylindrical axial bore that is sized to provide a maximum valve flow coefficient. Peripheral threads on the insert mate with interior threads on the inlet of the valve body. A pair of bores on the face of the insert permit threaded insertion into the valve. The axial orifice bore through the insert is sized using experimentally-determined formulas related to the Reynolds numbers for the orifice and for the piping upstream of the insert.

Abstract: An improved method of flow control by developing a dimensionless model describing Reynolds number values of a pipe as a function of Reynolds numbers of a flow control device connected to the pipe. The model describes the effect on flow performance of the flow control device due to variations of choke sizes operatively installed in proximity to the flow control device. The model is then utilized to determine the characteristic dimension of a choke to be placed in proximity to a flow control device in order to achieve a desired flow coefficient value.