SU951250A1 - Device for regulating two gas flow consumption ratio - Google Patents

Description

This invention relates to automatic regulation and can be used to automatically maintain a predetermined ratio of the costs of two mixes of non-isothermal gas flows, for example, entering a gas burner or furnace (reactor).

Known controllers of the ratio of the specified purpose 1.

However, with sufficient simplicity of the design of the control systems, there is no cost adjustment when the temperature of at least one of the entrapment flows changes, which leads to destabilization of the weight ratios and violation of burning regimes.

The closest to the technical essence of the invention is a device for automatically controlling the ratio of gas flow rates and air, where, in order to improve the quality of regulation, nozzles and a receiver with two channels connected to a pneumatic diaphragm actuator are installed in the air box Control Valve

This device is simple in design, low-inertia, but unsuitable for operation with variations in air and gas temperatures.

The aim of the invention is to improve the accuracy of the device.

This goal is achieved by the fact that the device for controlling the ratio of the flow rates of the two gas flows, containing a pulse nozzle and receiving channels connected to the control chambers of the membrane actuator installed on the driven flow pipeline, has an adjustable one installed inside the pipeline of the driving flow the heat exchanger, the inlet of which is connected to the pipeline of the driven stream, and the outlet - with a pulse nozzle.

The drawing shows a scheme for re-validation of the ratio of the costs of the driven flow (gaea) and the leading flow (air),

Claims (2)

The control system has a pipeline 1 for supplying gas, a pipeline 2 for supplying air. The pipeline 1 has a regulator 3 connected to the pipe 2 by the impulse lines 4 and 5, through which the impulse is transmitted, perceived by the direct channels b and 7. The control impulse is formed by the impulse nozzles 8 installed coaxially with the channel 6 in the pipe 2. For supplying the control medium is a pulsed pipe on which there is a trimmer 10 and an adjustable heat exchanger containing a heat exchanger 11 placed in the pipe 2 at some distance behind the nozzle 8 and the channels and. 7. The device operates as follows. The gas to the pulsed nozzle 8 is supplied through the pulsed pipe 9 through an adjustable - resistance 10 and a heat exchanger 11.. In the absence of air flow in the pipeline 2 (Ug 0 gas, flowing out of the nozzle 8, enters the receiving channel B. The kinematic energy of the control jet is converted to a static pressure, which is transferred to the cavity of the membrane regulator connected to the regulator 3. In the absence of blowing, the pressure perceived by the channel b acts on the closing of the regulating valve. Air supply through pipeline 2 at a certain speed leads to a distortion of the trajectory of the control jet. At the same time, the perceived redistribution between channels b and 7. As the air velocity increases, the pressure in channel 7 increases and, in proportion to this pressure, the impulse acting on the opening of regulator 3 increases. This is the principle of operation of the device if the temperatures of the mixing media are equal or close to each other. temperature changes, such as air heating, the speed in the pipeline varies. However, this change cannot be arbitrary. The air velocity in pipeline 2 is determined by the operating factors and the cross section of the pipeline. in 360 °, where oL is the air excess factor — the theoretically necessary amount of air; cross-sectional area; pipeline g — fuel consumption. When the heat output of the unit is constant, the air preheating reduces fuel consumption, therefore, at a constant ot, the consumption of blowing air should also decrease. If the heat capacity of the unit when operating in cold air is V-Yn, then when operating in heated air, B P P 8 -QP + CclV ,. at(). Here the fuel consumption when working on heated air. Then the air velocity in the 4C pipeline B3bOO-f) P o.- 11 Here SbOO-f-T-p 8 The interaction of the jet with the flow is usually evaluated by the ratio of the velocity head of the media. In the absence of heating P. and 0., P Ui JBO in When heating and skipping the microheat exchanger Ruo-uo o G p. (- y nJ Thus, rvf This indicates that the degree of deviation of the control system from the parameters of operation on heated air depends on the amount of air preheating Estimating the order of magnitudes in the expression for K, we note that for industrial furnaces, where the heating is 30-0-400 ° C, the fraction is 0.77-0.82. This suggests that by adjusting the system to body 10 for a given range of changes in the coefficient of excess air in the cold mode, you can expect An insignificant deviation of the actual mode during heating Reduction of the deviation K from the K value corresponding to the setting when working in cold air is achieved by introducing the trimmer 10. In the adjustable resistance 10. The control medium is divided into two streams. the other is fed unheated. Immediately before the pulse nozzle 8, both streams are mixed and set to some average temperature. control environment. The described system of automatically maintaining the ratio of the flow rates of gas media is particularly promising for small industrial furnaces, heating boilers and other fire installations. Apparatus of the Invention A device for controlling the ratio of the flow rates of two gas streams, comprising a pulse nozzle and receiving channels connected to the control chambers of a diaphragm actuator mounted on the follower pipeline, which is designed to improve the accuracy of the device. , it contains an adjustable heat exchanger installed inside the pipeline of the leading flow, the inlet of which is connected to the pipeline of the driven flow, and the outlet to it pulse nozzle. Sources of information taken into account in the examination 1.Balashov V.A. and others. Automation of gas flow in industrial plants. - Col. Efficient use of gas fuel Kuibyshev, 1962. 2. Authors certificate of the USSR 228847, cl. Q 05D 11/02, 1963 prototype).