HEAT TRANSFER AND HYDRAULIC RESISTANCE IN SINGLE-PHASE FORCED CONVECTION IN ANNULAR CHANNELS WITH TWISTING WIRE INSERTS

In this paper the experimental results of a heat transfer and pressure drop in annular channels with continuous twisting on length at one-phase water flow are presented. For a flow twisting the wire was spirally coiled on the central body of an annular channel (diameter of a wire is equal to annular gap height). The generalizing associations for heat transfer calculation on the concave and convex surfaces at single-phase flow are presented. The heat transfer on a convex surface of an annular channel with a twisting is considerably more than the heat transfer on a concave surface. The design procedure of the friction factor for definition of pressure drop in annular channels with a continuous twisting on length is offered.