JP2010121965A - Low-temperature engine testing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a low-temperature engine testing apparatus capable of achieving the maintenance of the inner environment of a low-temperature test room and control of the wall deterioration at the same time. <P>SOLUTION: The low-temperature engine testing apparatus 10 includes: a small chamber 74 disposed on the wall 40 of the low-temperature testing room 30, which faces each of the low-temperature testing room 30 and a machine room 20 and through which an exhaust flue 58 passes with gaps 49 and 89, the exhaust flue leading the exhaust of the engine 50 to the machine room 20; a duct 80 for supplying dried air to the small chamber 74; and a pressure controller 100 for controlling the pressure of the small chamber 74 at lower than the pressure in the low-temperature testing room 30. For the low-temperature engine testing apparatus 10, the inner environment of the low-temperature testing room 30 can be maintained and the deterioration of the wall 40 can be controlled by setting up the small chamber 74 between the low-temperature room 30 and the machine room 20 and controlling the pressure therein. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a low temperature test apparatus for testing engine performance in a low temperature environment.

  One of the test apparatuses for testing engine performance in various temperature environments used is a low-temperature test apparatus. In the low-temperature test apparatus, it is necessary to exhaust the engine exhaust gas to the outside of the test chamber. For example, Patent Document 1 discloses a low temperature test apparatus in which a through hole is provided in a wall of a low temperature test chamber, and an exhaust pipe passing through the through hole is attached to the engine to perform a low temperature test of the engine.

JP 2006-78311 A

  FIG. 2 schematically shows the structure of the engine low-temperature test apparatus 110 of Patent Document 1. The low-temperature test apparatus 110 includes a low-temperature test chamber 30 that is kept at a low temperature and a room temperature machine room 20. The cryogenic test chamber 30 and the machine room 20 are separated by a wall 40. In the low temperature test chamber 30, the engine 50 is mounted on a mounting table 52, and an exhaust pipe 54 is attached to the engine 50. The exhaust pipe 54 is connected to a large exhaust flue 58 via a connector 56, and the exhaust flue 58 extends through the through hole 42 provided in the wall 40 to the machine room 20. Exhaust gas from the engine 50 is discharged out of the low temperature test chamber 30 through the exhaust pipe 54 and the exhaust flue 58.

When performing a low temperature test of the engine 50, it is required to keep the internal environment of the low temperature test chamber 30 in which the engine 50 is placed constant. That is, it is required to maintain the airtightness of the low temperature test chamber 30. In order to maintain the airtightness of the low temperature test chamber 30, it is preferable that the inner wall of the through hole 42 provided in the wall 40 and the outer wall of the exhaust flue 58 are in contact with each other.
On the other hand, high-temperature exhaust gas flows through the exhaust flue 58 via the exhaust pipe 54, and the exhaust flue 58 becomes hot. If the inner wall of the through-hole 42 and the outer wall of the exhaust flue 58 are in contact with each other, the wall 40 is heated by the high temperature exhaust flue 58 and the wall 40 is deteriorated. Further, in order to prevent the deterioration of the wall 40, it is necessary to form the wall 40 using a non-combustible material or a heat shield, and the cost of configuring the wall 40 (that is, the cost of configuring the engine low temperature test apparatus 110). Will increase. In order to suppress the deterioration of the wall 40, as shown in FIG. 2, a gap is provided between the inner wall of the through hole 42 and the outer wall of the exhaust flue 58, so that the outer wall of the exhaust flue 58 passes to the inner wall of the through hole 42. It is effective to suppress heat conduction directly. However, when a gap is provided between the inner wall of the through hole 42 and the outer wall of the exhaust flue 58, it is difficult to maintain the airtightness of the low temperature test chamber 30. That is, it is difficult to maintain the internal environment of the low temperature test chamber 30.

  When a gap is provided between the inner wall of the through hole 42 and the outer wall of the exhaust flue 58, at least the pressure in the low temperature test chamber needs to be higher than the pressure in the machine chamber. Otherwise, room temperature air in the machine room will flow into the low temperature test chamber and the temperature of the low temperature test chamber will rise. In addition, when a gap is provided between the inner wall of the through hole 42 and the outer wall of the exhaust flue 58, moisture contained in the air at normal temperature will be condensed when the air at normal temperature touches the low temperature air in the low temperature test chamber. There is also. In particular, when normal temperature air flows into the low temperature test chamber, condensation may occur in the low temperature test chamber.

However, during engine testing, the pressure in the low temperature test chamber may temporarily drop below the outside pressure. This will be described with reference to FIG.
FIG. 3 is a graph schematically showing the relationship between the engine speed N during the test, the intake air amount M of the engine, and the pressure P of the low temperature test chamber. The horizontal axis indicates the elapsed time. The solid line indicates the engine speed N. The dotted line indicates the intake air amount M of the engine. The two-dot chain line indicates the pressure P inside the low temperature test chamber based on the pressure outside the low temperature test chamber. As shown in FIG. 3, as the engine speed N increases, the intake air amount M of the engine increases. When the ratio of the intake air amount M of the engine is large with respect to the volume of the low temperature test chamber, when the intake air amount M of the engine increases, the pressure P of the low temperature test chamber decreases as shown by a circle 60 in FIG. The pressure inside the low temperature test chamber may temporarily decrease compared to the pressure outside the low temperature test chamber.

  When a gap is provided between the inner wall of the through hole 42 and the outer wall of the exhaust flue 58, when the pressure in the low temperature test chamber decreases compared to the pressure outside the low temperature test chamber, the air outside the low temperature test chamber Get inside. The temperature of the low temperature test chamber may rise or condensation may occur in the low temperature test chamber, and the internal environment of the low temperature test chamber may not be maintained.

  The present invention solves the above problems. That is, an object of the present invention is to provide an engine low-temperature test apparatus capable of simultaneously maintaining the internal environment of a low-temperature test chamber and suppressing wall deterioration.

  The present invention is embodied in an engine low temperature test apparatus. This engine low temperature test equipment is intended to test the performance of the engine when the engine is placed in the low temperature test chamber and the engine is operated in the low temperature test chamber. And a pressure regulator. The small rooms are provided on the walls of the low temperature test chamber and face the outside and the inside of the low temperature test chamber, respectively. That is, a small room penetrating the wall is provided on the wall of the low temperature test chamber. The exhaust pipe penetrates the small chamber with a gap, and guides the engine exhaust to the outside of the low temperature test chamber. More specifically, the exhaust pipe passes through the walls of the small chambers facing the outside and inside of the cryogenic test chamber, respectively. A gap is formed between the wall of the small chamber and the exhaust pipe, and the wall and the exhaust pipe are not in contact with each other. The duct supplies dry air to the small room. The pressure regulator keeps the pressure in the small chamber lower than the pressure in the cold test chamber. Note that the pressure in the small chamber only needs to be kept slightly lower than the pressure in the low temperature test chamber.

  In the engine low temperature test apparatus according to the present invention, a gap is formed between the wall of the small chamber and the exhaust pipe, and the wall of the small chamber and the exhaust pipe are not in contact with each other. Therefore, even when the exhaust pipe is heated by the exhaust gas flowing inside the exhaust pipe, the wall is not directly heated by the exhaust pipe. Thereby, heating of the wall is suppressed, and deterioration of the wall can be suppressed.

  On the other hand, the pressure in the small chamber is always kept lower than the pressure in the low temperature test chamber. When the pressure in the low temperature test chamber becomes lower than the external pressure, the pressure in the small chamber becomes lower than the pressure in the low temperature test chamber and the external pressure. Therefore, the outside air is prevented from flowing into the low temperature test chamber. At this time, outside air flows into the small room through the gap between the exhaust pipe and the wall, but since the small room is filled with dry air, no condensation occurs in the small room.

  In addition, since dry air is supplied to the small room through the duct, the occurrence of condensation is suppressed even when low-temperature air flows into the small room from the gap on the low-temperature test room side and the air in the small room is cooled. Is done. Depending on the temperature difference between the low temperature test chamber and the small room, it may not be possible to prevent the occurrence of condensation. In this low temperature test apparatus, the air in the low temperature test chamber and the air in the small room are mixed in the small room. Therefore, it is possible to keep the condensation in the small room.

  When the pressure in the low-temperature test chamber is higher than the external atmospheric pressure, the pressure regulator is preferably maintained so that the pressure in the small chamber is higher than the external atmospheric pressure. By adjusting the pressure of the small chamber in this way, the cold air flowing into the small chamber from the gap on the cold test chamber side mixes with the dry air supplied from the duct, and is on the opposite side of the cold test chamber. It flows out through the gap. Since the air in the small room is always discharged from the gap, the dry air can smoothly flow into the small room through the duct.

  ADVANTAGE OF THE INVENTION According to this invention, the engine low-temperature test apparatus which can achieve simultaneously maintenance of the internal environment of a low-temperature test chamber and suppression of wall deterioration is realizable.

The main features of the embodiment described below will be summarized.
(Feature 1) A through-hole is formed in the wall of the low-temperature test chamber. A first shielding plate is provided inside the low temperature test chamber of the through hole. A second shielding plate is provided outside the low temperature test chamber of the through hole. A small room is formed by the through hole, the first shielding plate, and the second shielding plate.
(Feature 2) A first through hole is formed in the first shielding plate. The exhaust pipe passes through the first through hole. The first through hole is wider than the cross section of the exhaust pipe, and a gap is formed over the entire circumference between the inner wall of the first through hole and the outer wall of the exhaust pipe.
(Characteristic 3) The 2nd through-hole is formed in the 2nd shielding board. The exhaust pipe passes through the second through hole. The second through hole is opened wider than the cross section of the exhaust pipe, and a gap is formed over the entire circumference between the inner wall of the second through hole and the outer wall of the exhaust pipe.
(Feature 4) The dry air supplied to the duct is set to a temperature equal to or higher than the temperature outside the low temperature test chamber.

  FIG. 1 schematically shows the configuration of an engine low temperature test apparatus 10 according to an embodiment of the present invention. In FIG. 1, the entire low temperature test apparatus 10 is not drawn, and only a part necessary for explaining the present invention is drawn. As shown in FIG. 1, the engine low temperature test apparatus 10 includes a machine room 20 and a low temperature test room 30, and the machine room 20 and the low temperature test room 30 are separated by a wall 40. The low temperature test chamber 30 is maintained in a low temperature state and in a low humidity state, and the occurrence of condensation in the low temperature test chamber 30 is suppressed. The temperature in the machine room 20 is normal temperature. The engine 50 is mounted on a mounting table 52 in the low temperature test chamber 30. In the engine low temperature test apparatus 10 of the present embodiment, the engine 50 is placed in the low temperature test chamber 30 to operate the engine 50, and the performance of the engine 50 in a low temperature environment is tested.

The wall 40 is provided with a through hole 42 penetrating from the machine room 20 to the low temperature test room 30. An exhaust pipe 54 is attached to the engine 50 placed in the low temperature test chamber 30. The exhaust pipe 54 is connected to a large exhaust flue 58 via a connector 56. The exhaust flue 58 extends through the through-hole 42 provided in the wall 40 to the machine room 20 and is supported by the support member 70 and the support column 59, and the tip thereof extends below the floor of the machine room 20. It is growing.
The through hole 42 opens wider than the cross section of the exhaust flue 58, and a heat insulating material 46 is provided so as to cover the inner wall thereof. A first shielding plate 48 that covers the low temperature test chamber 30 side of the through hole 42 is provided on the side surface of the heat insulating material 46 on the low temperature test chamber 30 side. A first through hole 47 is formed in the first shielding plate 48. The first through hole 47 opens slightly wider than the cross section of the exhaust flue 58, and the exhaust flue 58 passes through the first shielding plate 48 through the first through hole 47 and the first through hole 47. Between the inner wall and the outer wall of the exhaust flue 58, a slight gap 49 is formed over the entire circumference. That is, the exhaust flue 58 is not in contact with the wall (the wall 40 and the first shielding plate 48) that shields the low temperature test chamber 30 from the outside.

  A support member 70 is disposed inside the through hole 42. The support member 70 is fixed by a member (not shown) and supports the exhaust flue 58. A gap 72 is provided between the support member 70 and the heat insulating material 46. The formation of the gap 72 prevents the exhaust flue 58 and the wall 40 from contacting each other via the heat insulating material 46 and the support member 70.

A duct 80 is provided on the machine room 20 side of the wall 40. The duct 80 is supported on the wall 40 by a column 82. The duct 80 is disposed so as to cover a portion of the wall 40 on the machine room 20 side where the through hole 42 is formed, and extends in the vertical direction through the through hole 42.
In the duct 80, a facing portion 80 a that is a portion facing the through hole 42 has a thinner cross section than a non-facing portion 80 b that is a portion not facing the through hole 42. A first hole 84 is formed on the facing portion 80a on the low temperature test chamber 30 side. The heat insulating material 46 is connected to the outer wall of the duct 80 around the first hole 84, so that the air in the through hole 42 and the duct 80 can flow through the gap 72. Further, a second hole 88 is formed on the machine room 20 side of the facing portion 80a. A second shielding plate 86 covering the second hole 88 is provided on the outer wall of the duct 80 around the second hole 88. A second through hole 87 is formed in the second shielding plate 86. The second through hole 87 opens slightly wider than the cross section of the exhaust flue 58, and the exhaust flue 58 passes through the second shielding plate 86 through the second through hole 87, and the second through hole 87. Between the inner wall and the outer wall of the exhaust flue 58, a slight gap 89 is formed over the entire circumference. That is, also here, the exhaust flue 58 is not in contact with the wall (the wall 40 and the second shielding plate 86) that shields the low temperature test chamber 30 from the outside.

  In the engine low temperature test apparatus 10 of the present embodiment, the exhaust flue 58 and the wall 40 are not in contact with each other. Therefore, even when the exhaust flue 58 is heated by the high-temperature exhaust discharged from the engine 50, the wall 40 is not directly heated by the exhaust flue 58. It can suppress that the wall 40 deteriorates by heating. In addition, it is not necessary to form the wall 40 using a non-combustible material or a heat shield in order to prevent deterioration due to heating.

  In the engine low temperature test apparatus 10 according to the present embodiment, the small chamber 74 is configured by the heat insulating material 46, the first shielding plate 48, and the second shielding plate 86 so as to surround the through hole 42 provided in the wall 40. A structure in which a duct 80 is connected to the small chamber 74 is formed. The small room 74 is supplied with dry air at normal temperature through the duct 80.

  As will be described later, the pressure regulator 100 maintains the pressure in the small chamber 74 lower than the pressure in the low temperature test chamber 30. Therefore, in the engine low temperature test apparatus 10 according to the present embodiment, air in the low temperature test chamber 30 flows into the small chamber 74 through the gap 49. When the pressure in the low temperature test chamber 30 is higher than the pressure in the machine chamber 20 (external pressure), the pressure regulator 100 maintains the pressure in the small chamber 74 higher than the pressure in the machine chamber 20. To do. That is, when the pressure in the low temperature test chamber 30 is higher than the pressure (external pressure) in the machine chamber 20, the pressure regulator 100 reduces the pressure in the small chamber 74 to be lower than the pressure in the low temperature test chamber 30. And higher than the pressure in the machine room 20. Therefore, the air in the small room 74 flows out to the machine room 20 through the gap 89.

  A condensed water tank 96 is placed below the duct 80. In the condensed water tank 96, condensed water condensed in the small room 74 is collected. A valve 98 is installed at the bottom of the condensed water tank 96, and the condensed water stored in the condensed water tank 96 is discharged to the outside through the valve 98.

Inside the duct 80, a fan 90 is installed at a position from the facing portion 80a of the duct 80 toward the non-facing portion 80b. In the small room 74, a pressure gauge 92 for measuring the pressure in the small room 74 is installed. Further, a pressure regulating valve 94 is installed at the facing portion 80 a of the duct 80.
A pressure gauge 22 is installed in the machine room 20, and a pressure gauge 32 is installed in the low temperature test chamber 30. A pressure regulator 100 is installed in the machine room 20. The pressure regulator 100 is connected to the pressure gauges 22, 32, and 92, and monitors the pressures in the machine room 20, the small room 74, and the low temperature test room 30. The pressure regulator 100 is connected to the fan 90 and the pressure regulating valve 94. The pressure regulator 100 adjusts the pressure of the small chamber 74 by adjusting the degree of opening and closing of the fan 90 and the pressure regulating valve 94.

  In the engine low temperature test apparatus 10 according to the present embodiment, the pressure regulator 100 adjusts the pressure in the small chamber 74 to be lower than the pressure in the low temperature test chamber 30. Therefore, the air in the small chamber 74 does not flow into the low temperature test chamber 30. Thereby, the internal environment of the low temperature test chamber 30 can be maintained, and the performance of the engine under a certain environment can be accurately measured.

On the other hand, the air in the low temperature test chamber 30 flows into the small room 74 and the air in the small room 74 is cooled.
In the engine low temperature test apparatus 10 according to the present embodiment, dry air is supplied to the small room 74 through the duct 80, and the occurrence of condensation in the small room 74 is suppressed. Further, depending on the temperature difference between the low temperature test apparatus 10 and the small room 74, the occurrence of condensation in the small room 74 may not be completely prevented. In the engine low temperature test apparatus 10 according to the present embodiment, even when condensation occurs, the generation location can be kept in the small chamber 74. Thus, condensation is prevented from occurring in both the machine room 20 and the low temperature test chamber 30, and deterioration of the wall 40 due to repeated humidification and drying due to condensation is suppressed. The condensed water generated in the small room 74 is collected in the condensed water tank 96 through the duct 80.

  Air flowing into the small room 74 from the low temperature test chamber 30 through the gap 49 is mixed with dry air supplied from the duct 80 in the small room 74. The pressure in the small chamber 74 is set higher than the pressure in the machine chamber 20. Therefore, the air mixed in the small room 74 flows out into the machine room 20 through the gap 89. The gap 49 is narrow, and the volume of air flowing from the low temperature test chamber 30 into the small room 74 is smaller than that of air supplied from the duct 80 to the small room 74. Therefore, the air mixed in the small room 74 is still kept at room temperature. Therefore, even when the air mixed in the small room 74 flows into the machine room 20, no condensation occurs in the machine room 20. Condensation is reliably prevented from occurring on the machine room 20 side of the wall 40.

  In the engine low-temperature test apparatus, as shown in FIG. 3, when the intake air amount M of the engine increases as the engine speed N increases, the pressure in the low-temperature test chamber 30 decreases. It is possible that the pressure in the low temperature test chamber 30 temporarily drops below the pressure in the machine chamber 20.

In the engine low temperature test apparatus 10 of the present embodiment, a small chamber 74 is provided between the low temperature test chamber 30 and the machine room 20. The pressure in the small chamber 74 is maintained lower than the pressure in the low temperature test chamber 30 by the pressure regulator 100. When the pressure in the low temperature test chamber 30 is lower than the pressure in the machine chamber 20, the pressure in the small chamber 74 is lower than the pressure in the machine chamber 20. Therefore, when the pressure in the low temperature test chamber 30 is temporarily lower than the pressure in the machine chamber 20, the air in the machine chamber 20 flows into the small chamber 74, but does not flow into the low temperature test chamber 30. Absent.
Further, the air flowing into the small room 74 from the machine room 20 through the slight gap 89 is mixed with the dry air supplied from the duct 80 in the small room 74. The air flowing from the machine room 20 into the small room 74 has a smaller volume than the air supplied from the duct 80 to the small room 74. Therefore, the air mixed in the small chamber 74 is kept at the pressure of the small chamber 74. Therefore, the air mixed in the small chamber 74 does not flow into the low temperature test chamber 30.

  According to the engine low-temperature test apparatus 10 of the present embodiment, even if the pressure in the low-temperature test chamber 30 is temporarily lower than the external pressure, the external air passes through the gap around the exhaust flue 58 and is subjected to the low-temperature test. It does not flow into the chamber 30. Thereby, the low temperature environment in the low temperature test chamber 30 is maintained, and the performance of the engine 50 can be accurately tested. Moreover, according to the engine low temperature test apparatus 10 of the present embodiment, the deterioration of the wall 40 due to heating or humidification can be reliably prevented. As a result, the engine low-temperature test apparatus 10 can have a long life, and the cost of configuring the engine low-temperature test apparatus 10 can be reduced.

As mentioned above, although the Example of this invention was described in detail, these are only illustrations and do not limit a claim. The technology described in the claims includes various modifications and changes of the specific examples illustrated above.
The technical elements described in this specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology exemplified in this specification or the drawings can achieve a plurality of objects at the same time, and has technical usefulness by achieving one of the objects.

It is a figure which shows the low-temperature test apparatus of an Example. It is a figure which shows the conventional low-temperature test apparatus. It is a figure which shows the relationship between the operating condition of an engine, and the pressure of a low-temperature test chamber.

Explanation of symbols

10: Low temperature test apparatus 20: Machine room 22, 32, 92: Pressure gauge 30: Low temperature test room 40: Wall 42: Through hole 46: Thermal insulation material 47: First through hole 48: First shielding plate 50: Engine 54: Exhaust pipe 58: Exhaust flue 70: Support member 74: Small chamber 80: Duct 84: First hole 86: Second shielding plate 87: Second through hole 88: Second hole 90: Fan 94: Pressure adjusting valve 96: Condensed water tank 98: Valve 100: Pressure regulator M: Graph showing engine intake amount N: Graph showing engine speed P: Graph showing pressure in low temperature test chamber

Claims (1)

Engine low temperature test equipment,
A small room located on the wall of the cryogenic test chamber and facing the outside and inside of the cryogenic test chamber,
An exhaust pipe that penetrates the small chamber with a gap and guides the engine exhaust to the outside of the low temperature test chamber;
A duct for supplying dry air to the small room;
A pressure regulator that keeps the pressure in the small chamber lower than the pressure in the low temperature test chamber;
A low-temperature test apparatus comprising:

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