| In the pipe transportation, the velocity of flow and the flow's ability of transporting is related very much. It is contradictory and impossible to lowly flow with high concentration in old, straight flow way. So we consider to disparate the transportation and suspension in one flow. The spiral flow in the round pipe can be thought axial and tangential current velocity, namely the compound of axial straight current and forced whirling current. The principle of spiral flow is to transport material by axial current, suspend that by whirling current. So it is possible to flow lowly with high concentration of grain. In according to the condition of flow boundary the spiral flow can be separated into two kinds. One is generated locally, the other is generated along the pipe. Because the water's viscosity and boundary's friction, forced whirling current would decayed into straight current duringthe transportation. So in order to the whirling current status, it must be to set a special instrument to make the current whirling in the pipe. This is continuing-way rotational instrument. Continuing-way rotational instrument is also continuous one locally which can make flow rotating in the pipe. It can make the decaying spiral flow go on rotating, even rotating strongly, getting the purpose of transporting grain.Based on the model experiment the paper give a concept of continuing-way rotational instrument and decide its parameter by analyzing the flow field of spiral flow in horizontal round pipes. Then testing the flow field behind the continuous rotational instrument and making a comparison with numerical simulation, we obtain the effect of continuous rotating instrument on current, making a conference to industrial application. Following is the major content of the paper: 1.Having a theory analyzing on the symmetry spiral flow, inducing reasonable assumption and coordinates changes, the paper simplify the N-S differential equation, which come from the independent variable of velocity and pressure, and set up aturbulence numerical model of flow fields locally generated by continuous way in steady flow.2. During the calculation on numerical model, the paper choose the better algorithm — SIMPLE. And the division of grid is displaced (not located), which make the calculation much easier. The Gauss—Seidel iteration method is normal in the difference calculation, so applied in the numerical model, which exclude the complicated matrix and simplify the procedure.3. Giving the concept of continuous whirling instrument, the whirling flow field behind and in front of the instrument is tested during the physical model process. By comparing the former whirling flow (without continuous whirling instrument) and the new flow (with continuous whirling instrument), the paper demonstrate effect of continuous whirling flow on the upstream and downstream current.4. Having an analyze on the result of physical model, the characteristics of flow fields locally generated by continuous way is obtained. The result of physical model experiment is also similar with the one of numerical model. The axial currentvelocity present analogue logarithmic distribution along pipe of the spiral flow from the logarithmic distribution of straight flow, and spread downstream. The major energy is concentrated on center of pipe, and there is minimal on the pipe boundary. The axial current is distributed with the form of single peak in the center of pipe axis. The tangential current is symmetric on the section. If neglecting the effect of boundary, the tangential current is distribution with the linear form. The whirling intensity can be screened by the linear slope coefficient. The pressure presents the characteristics: high on the boundary and low in the center of pipe, the pressure tend to increase radially. While the whirling current decaying along the stream, pressure head decrease. The radial current is negligible comparing the axial and tangential current, and can be omitted.
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