JP2010230486A - Premixed gas supply testing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a premixed gas supply testing device capable of reducing waiting time and improving test efficiency by reducing abrupt expansion of volume of premixed gas in a combustion vessel when supplying gas for stabilizing temperature and pressure of the premixed gas, and capable of stabilizing fuel concentration in the premixed gas immediately after starting to supply gas and temperature of the premixed gas. <P>SOLUTION: In the device for introducing the premixed gas into the combustion vessel 1 for performing combustion-related tests, a gas supply bypass exhaust line 14 including a gas supply bypass exhaust valve 13 is branched from a premixed gas supply line 6 between a gas heater 4 and a gas supply valve 5 for connecting to an exhaust line 9 at a downstream of a vacuum pump 8, an exhaust auxiliary valve 15 is provided in the exhaust line 9 between an exhaust valve 7 and the vacuum pump 8, and a pressure control line 17 including a pressure control valve 16 is branched from the exhaust line 9 between the exhaust valve 7 and an exhaust auxiliary valve 15 for connecting to the exhaust line 9 at a downstream side of the vacuum pump 8. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a premixed gas supply test apparatus for performing various combustion-related tests such as an engine in which a premixed gas in which fuel and air are premixed is burned in a combustion chamber.

  In recent years, premixed compression auto-ignition combustion type engines have attracted attention from the viewpoint of reducing harmful emissions and saving energy.

  The premixed compression self-ignition combustion type engine takes advantage of the features of both conventional gasoline engines and diesel engines, has better fuel efficiency, and can achieve significantly lower pollution of exhaust gas than conventional engines. In addition, the emission of nitrogen oxides (NOx) and soot is low, and the efficiency can be as high as that of a diesel engine.

  Incidentally, in the premixed compression self-ignition combustion type engine, fuel and air are mixed to form a premixed gas, and then the premixed gas is supplied to the combustion chamber and compressed by a piston so as to be self-ignited. This combustion type engine can be ignited and burned even with a lean premixed gas mixture of a large amount of air and a small amount of fuel, so the combustion temperature can be kept low and NOx generation can be reduced. It is.

  In addition, since fuel and air can be mixed thoroughly and burned homogeneously without causing oxygen shortage, soot does not occur.In addition, this combustion system engine burns at a high compression ratio comparable to that of a diesel engine. It has the feature of high thermal efficiency.

  For example, Patent Document 1 shows a general technical level of the engine of the premixed compression auto-ignition combustion system as described above.

  By the way, in the premixed compression auto-ignition combustion type engine and the like as described above, a test apparatus simulating the engine and the like in order to confirm the combustion state and flame propagation state of the premixed gas in the cylinder as the combustion container. Is required.

  FIG. 4 shows an example of a conventional premixed gas supply test apparatus, in which each of the mass flow controllers 2 and 2 is connected to a combustion container 1 in which a combustion-related test for confirming a combustion state, a flame propagation state, and the like is performed. A premixed gas supply in which a premixed gas obtained by premixing fuel and air supplied via 3 can be supplied into the combustion container 1 and a gas heater 4 and a supply valve 5 (SV1) are provided in the middle. A premixed gas supply line between the gas heater 4 and the supply valve 5 is connected to an exhaust line 9 provided with an exhaust valve 7 (SV2) and a vacuum pump 8 in the middle. 6 is provided with a temperature sensor 10 for detecting the temperature 10a of the premixed gas, and the combustion vessel 1 is provided with a pressure sensor 11 for detecting the pressure 11a in the combustion vessel 1, and further detected by the temperature sensor 10. Premixed air temperature Control signals 2a and 3a are output to the mass flow controllers 2 and 3 based on the pressure 11a in the combustion container 1 detected by the pressure sensor 11 and the open / close signal 5a to the intake valve 5 and the exhaust valve 7, respectively. A controller 12 that outputs 7a and outputs a drive signal 8a to the vacuum pump 8 is provided.

  The wall surface of the combustion container 1 is always heated by a heater (not shown) so as to have the same temperature as the premixed gas temperature 10a.

  Next, the operation of the conventional premixed gas supply test apparatus shown in FIG. 4 will be described with reference to FIG. In FIG. 5, the controller 12 is not shown.

  First, as shown in FIG. 5 (a), the exhaust valve 5 is evacuated by the operation of the vacuum pump 8 with the air supply valve 5 closed and the exhaust valve 7 opened. The pressure 11a in the combustion container 1 decreases as shown in FIG. At this time, the mass flow controllers 2 and 3 are held closed.

Subsequently, as shown in FIG. 5B, as the air supply stroke, the air flow valve 5 is opened and the exhaust valve 7 is closed, and the mass flow controllers 2 and 3 are operated as shown in FIG. After opening and raising the pressure 11a in the combustion container 1, the mass flow controllers 2 and 3 are closed, the air supply valve 5 and the exhaust valve 7 are repeatedly opened and closed, and fine adjustment is performed. When the pressure 11a is stabilized at a predetermined pressure, the supply of air is completed (see FIG. 5C). Thereafter, as shown in FIG. 5D, the combustion state and the flame propagation state in the combustion container 1 are obtained. A combustion-related test is performed to confirm the above.
JP 2003-239795 A

  However, in the conventional premixed gas supply test apparatus as described above, when the premixed gas is supplied into the pre-evacuated combustion container 1, the temperature 10a of the premixed gas decreases due to rapid volume expansion, Further, since the operations of the mass flow controllers 2 and 3 and the gas heater 4 are not stable immediately after the start of the supply of the premixed gas, there is a disadvantage that the fuel concentration in the premixed gas and the temperature 10a of the premixed gas become unstable. It was.

  Further, in order to compensate for the decrease in the temperature 10a of the premixed gas, the temperature 10a of the premixed gas must be heated to a predetermined temperature by heat transfer from the wall surface of the combustion container 1, and this heating causes the Since the pressure 11a inside the combustion vessel 1 also rises and becomes difficult to stabilize, there is also a problem that the waiting time becomes long and the test efficiency decreases.

  In view of such circumstances, the present invention can reduce the rapid volume expansion of the premixed gas in the combustion container during supply, stabilize the temperature and pressure of the premixed gas, and start the supply of air. It is an object of the present invention to provide a premixed gas supply test apparatus that can stabilize the fuel concentration in the premixed gas immediately after that and the temperature of the premixed gas, thereby shortening the waiting time and improving the test efficiency.

The present invention provides a premixed gas supply test apparatus for introducing a premixed gas in which fuel and air are premixed into a combustion container and performing a combustion-related test in the combustion container.
Premixed gas supply means for supplying a premixed gas obtained by premixing fuel and air respectively supplied via a flow rate regulator into the combustion container;
An exhaust means for discharging the gas in the combustion container to the outside,
The exhaust means has a pressure control valve;
An air supply stroke in which the pressure in the combustion container is set to a predetermined pressure by adjusting the opening of the pressure control valve of the exhaust means while supplying the premixed gas into the combustion container by the premixed gas supply means. The present invention relates to a premixed gas supply test apparatus characterized in that

  According to the above means, the following operation can be obtained.

  As described above, the pressure in the combustion container is set to a predetermined pressure by adjusting the opening of the pressure control valve of the exhaust means while supplying the premixed gas into the combustion container by the premixed gas supply means. When the pre-mixed gas is supplied into the combustion container, the pre-mixed gas is supplied while being partially exhausted to the outside. Rapid volume expansion hardly occurs and the temperature of the premixed gas does not decrease.

In the premixed gas supply test apparatus, the premixed gas supply means has a supply air bypass exhaust line provided with a supply air bypass exhaust valve in the middle,
As an air supply preparatory process before performing the air supply stroke, it can be configured to discharge the premixed gas immediately after the start of supply from the supply air bypass exhaust line by opening the supply air bypass exhaust valve, In this way, even if the fuel concentration in the premixed gas or the temperature of the premixed gas is unstable immediately after the start of the supply of the premixed gas, the fuel concentration or temperature is unstable. Since the premixed gas is discharged to the outside from the supply air bypass exhaust line, the premixed gas after the fuel concentration and temperature are stabilized can be supplied into the combustion container.

Further, the exhaust means has a vacuum pump,
As an exhaust stroke before performing the air supply preparation stroke, the inside of the combustion container can be evacuated by the operation of the vacuum pump.

  As a result, when the supply stroke is completed, there is almost no decrease in the temperature of the premixed gas, the temperature difference between the combustion vessel wall surface and the premixed gas becomes small, and the combustion vessel accompanying the heating of the premixed gas Since the increase in internal pressure is also minimized, the waiting time can be shortened and the test efficiency can be increased.

  According to the premixed gas supply test apparatus of the present invention, it is possible to reduce the rapid volume expansion of the premixed gas in the combustion container during supply, and to stabilize the temperature and pressure of the premixed gas, It is possible to stabilize the fuel concentration in the premixed gas immediately after the start of air supply and the temperature of the premixed gas, and to achieve an excellent effect that the waiting time can be shortened and the test efficiency can be improved.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

  1 to 3 show an example of an embodiment of the present invention. In the figure, the same reference numerals as those in FIGS. 4 to 6 denote the same components, and the basic configuration is shown in FIGS. 6 is the same as the conventional one shown in FIG. 6, but the feature of this illustrated example is that an air supply bypass exhaust valve 13 (SV3) is provided on the way as shown in FIGS. The exhaust flow line 14 is branched from the middle of the premixed gas supply line 6 between the gas heater 4 and the supply valve 5 and connected to the exhaust line 9 on the downstream side of the vacuum pump 8, whereby the mass flow controllers 2, 3 are respectively connected. A premixed gas obtained by premixing fuel and air supplied via the gas can be supplied into the combustion container 1 by opening the supply valve 5 and supplied by opening the supply bypass exhaust valve 13. Premixed gas that can be discharged to the outside from the bypass exhaust line 14 A pressure control line that constitutes a gas means 18 and is provided with an exhaust auxiliary valve 15 (SV4) in the middle of the exhaust line 9 between the exhaust valve 7 and the vacuum pump 8, and a pressure control valve 16 (PCV) in the middle. 17 is branched from the exhaust line 9 between the exhaust valve 7 and the exhaust auxiliary valve 15 and connected to the exhaust line 9 on the downstream side of the vacuum pump 8, whereby the exhaust valve 7 and the exhaust auxiliary valve 15 are connected. The inside of the combustion container 1 can be evacuated by the opening operation and the operation of the vacuum pump 8, and the pressure 11 a in the combustion container 1 is adjusted by opening the exhaust valve 7 and adjusting the opening of the pressure control valve 16. The exhaust means 19 that can be set to a predetermined pressure is configured.

  The air supply bypass exhaust valve 13 of the premixed air supply means 18 is controlled to open and close by an open / close signal 13a output from the controller 12, and the exhaust auxiliary valve 15 of the exhaust means 19 is output from the controller 12. The pressure control valve 16 of the exhaust means 19 is adjusted by an opening adjustment signal 16 a output from the controller 12.

  Next, the operation of the illustrated example will be described.

  First, as shown in FIG. 2A, the air supply valve 5, the air supply bypass exhaust valve 13 and the pressure control valve 16 of the exhaust means 19 of the premixed air supply means 18 are closed and the exhaust means 19 is closed. With the exhaust valve 7 and the auxiliary exhaust valve 15 being opened, the exhaust pump 19 of the exhaust means 19 is operated to evacuate the combustion container 1 and the pressure 11a in the combustion container 1 is evacuated. Decreases as shown in FIG. At this time, the mass flow controllers 2 and 3 of the premixed gas supply means 18 are kept closed.

  Subsequently, as shown in FIG. 2 (b), the air supply valve 5, the exhaust valve 7, the exhaust auxiliary valve 15, and the pressure control valve 16 are closed, the air supply bypass exhaust valve 13 is opened, and the mass flow controller is further opened. By opening 2 and 3 as shown in FIG. 3, when the premixed gas immediately after the start of the supply is discharged from the supply air bypass exhaust line 14 to the exhaust line 9 as an air supply preparation process, immediately after the premixed air supply starts. Since the operations of the mass flow controllers 2 and 3 and the gas heater 4 are not stable, even if the fuel concentration in the premixed gas or the temperature 10a of the premixed gas is unstable, the fuel concentration or the temperature 10a is not stable. Since the stable premixed gas is discharged from the supply air bypass exhaust line 14 to the exhaust line 9, the premixed gas after the fuel concentration and the temperature 10a are stabilized, In the subsequent air supply stroke (see FIG. 2C), the air supply valve 5, the exhaust valve 7 and the pressure control valve 16 are opened, and the air supply bypass exhaust valve 13 and the exhaust auxiliary valve 15 are closed. It becomes possible to quickly supply into the combustion container 1.

  In the air supply process after the completion of the air supply preparation process, the pressure control is performed with the air supply valve 5 and the exhaust valve 7 open, and the air supply bypass exhaust valve 13 and the exhaust auxiliary valve 15 are closed. When the opening of the valve 16 is adjusted, the pressure 11a in the combustion container 1 is set to a predetermined pressure. In this way, when the premixed gas is supplied into the combustion container 1 that has been evacuated in advance, the pre-mixed gas is supplied in advance. Since a part of the air-fuel mixture is exhausted from the pressure control line 17, the air supply is performed, so that rapid volume expansion in the combustion container 1 hardly occurs and the temperature 10a of the pre-air mixture does not decrease.

  After the completion of the air supply stroke, as shown in FIG. 2D, when the air supply valve 5, the exhaust valve 7, the exhaust auxiliary valve 15, and the pressure control valve 16 are closed, and the air supply bypass exhaust valve 13 is opened. The gas remaining in the premixed gas supply line 6 is discharged from the supply air bypass exhaust line 14 to the exhaust line 9, and as shown in FIG. 2 (e), the combustion state and the flame propagation state in the combustion container 1 A combustion-related test is performed to confirm the above.

  As a result, when the supply stroke is completed, there is almost no decrease in the temperature 10a of the premixed gas, the temperature difference between the wall surface of the combustion container 1 and the premixed gas becomes small, and the heating with the premixed gas is performed. Since the rise in the pressure 11a inside the combustion container 1 can be suppressed to the minimum, the waiting time can be shortened and the test efficiency can be increased.

  In this way, the rapid volume expansion of the premixed gas in the combustion container 1 during the supply of air can be reduced, the temperature 10a and the pressure 11a of the premixed gas can be stabilized, and the premixed gas immediately after the start of supply The fuel concentration and the premixed gas temperature 10a can be stabilized, and the waiting time can be shortened and the test efficiency can be improved.

  In addition, the premixed gas supply test apparatus of the present invention is not limited to the above-described illustrated example, and is not limited to the mass flow controller, and any flow controller may be used. It goes without saying that a gas heater is not necessarily provided depending on the combustion-related test, and various other changes can be made without departing from the scope of the present invention.

It is a schematic block diagram which shows an example of the form which implements this invention. It is an operation state figure in an example which carries out the present invention, (a) is an exhaust stroke, (b) is an air supply preparation stroke, (c) is an air supply stroke, (d) is an air supply completion state, ( e) It is a figure which shows a combustion related test implementation state, respectively. It is a timing chart which shows the relationship between the opening / closing timing of each valve | bulb and massflow controller in an example which implements this invention, and a pressure. It is a schematic block diagram which shows an example of the conventional premixed gas supply test apparatus. FIG. 5 is an operation state diagram in the conventional example of FIG. 4, where (a) is an exhaust stroke, (b) is an air supply stroke, (c) is an air supply completion state, and (d) is a combustion related test implementation state. It is. It is a timing chart which shows the relationship between the opening / closing timing of each valve | bulb and massflow controller in a prior art example, and a pressure.

1 Combustion vessel 2 Mass flow controller (flow controller)
2a Control signal 3 Mass flow controller (flow controller)
3a Control signal 4 Gas heater 5 Supply valve 5a Open / close signal 6 Premixed gas supply line 7 Exhaust valve 7a Open / close signal 8 Vacuum pump 8a Drive signal 9 Exhaust line 10 Temperature sensor 10a Temperature 11 Pressure sensor 11a Pressure 12 Controller 13 Supply air Bypass exhaust valve 13a Open / close signal 14 Supply air bypass exhaust line 15 Exhaust auxiliary valve 15a Open / close signal 16 Pressure control valve 16a Opening control signal 17 Pressure control line 18 Premixed air supply means 19 Exhaust means

Claims (3)

In a premixed gas supply test apparatus for introducing a premixed gas in which fuel and air are premixed into a combustion container and performing a combustion-related test in the combustion container,
Premixed gas supply means for supplying a premixed gas obtained by premixing fuel and air respectively supplied via a flow rate regulator into the combustion container;
An exhaust means for discharging the gas in the combustion container to the outside,
The exhaust means has a pressure control valve;
An air supply stroke in which the pressure in the combustion container is set to a predetermined pressure by adjusting the opening of the pressure control valve of the exhaust means while supplying the premixed gas into the combustion container by the premixed gas supply means. A premixed gas supply test apparatus characterized by comprising The premixed gas supply means has a supply bypass exhaust line provided with a supply bypass exhaust valve in the middle;
The premixed air immediately after the start of supply is discharged from the supply air bypass exhaust line to the outside by opening the supply air bypass exhaust valve as an air supply preparation step before performing the air supply stroke. Premixed gas supply test equipment. The exhaust means has a vacuum pump;
The premixed gas supply test apparatus according to claim 2, wherein the combustion chamber is evacuated by an operation of the vacuum pump as an exhaust stroke before performing the air supply preparation stroke.

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