1. A method for cleaning a stationary gas turbine unit during operation, wherein the unit comprises: a turbine; a compressor driven by the turbine, the compressor having an air inlet; and an air inlet duct arranged upstream of the air inlet of the compressor, the inlet duct having an acceleration duct adjoining the inlet of the compressor and having decreasing cross section in an air flow direction in order to increase the velocity of the air moving through the acceleration duct, with the air flow having a final velocity at the inlet to the compressor; the method comprising:
providing at least one spray nozzle positioned at the acceleration duct; and
introducing a spray of cleaning fluid within the acceleration duct wherein the cleaning fluid is forced through the at least one spray nozzle under sufficient pressure so as to form a spray of drops that penetrate the air flow, and with the spray being directed substantially parallel to and in the same direction as the direction of the air flow.
2. A method of claim 1, wherein the drops of the spray have a mean size that is less than around 150 \u03bcm.
3. A method of claim 1, wherein the air velocity is at least 40 percent of the final velocity at the compressor inlet.
4. A method of claim 1, wherein the drops of the fluid spray acquire a slip ratio of at least 0.8 at the compressor inlet.
5. A method of claim 1, wherein the cleaning fluid is forced through the spray nozzle with a pressure drop that is dependent on the location of the nozzle, and with the pressure drop within the acceleration duct being greater than a pressure drop occurring in the inlet upstream of the acceleration duct.
6. A method of claim 1, wherein cleaning fluid is forced through the spray nozzle with a pressure drop that is dependent on the location of the nozzle, and with the pressure drop within the acceleration duct being greater than a pressure drop occurring in the inlet upstream of the acceleration duct so that the drops of the spray stay in the air flow, to avoid leaving a liquid film within the inlet duct.
7. A method as claimed in claim 1, wherein the fluid spray is established so that a substantial proportion of its drops have a mean size within the interval of around 50-150 \u03bcm.
8. A method as claimed in claim 7, wherein the fluid spray drops are given a mean size of around 70 \u03bcm.
9. A method as claimed in claim 1, wherein the fluid spray drops are caused to acquire a slip ratio of at least 0.9 at the compressor inlet.
10. A method of claim 1, wherein the drops contact a compressor blade and a compressor stator vane.
11. A method of claim 1, wherein the drops have a mean size that remains substantially constant between about 50 to about 150 \u03bcm.
12. A method of claim 1, wherein the turbine is rotated with the aid of a start motor.
13. A method of claim 1, wherein a fuel is burned in a combustion chamber of the gas turbine unit.
14. A method for cleaning a stationary gas turbine unit during operation, wherein the unit comprises: a turbine; a compressor driven by the turbine, the compressor having an air inlet; an air inlet duct arranged upstream of the air inlet of the compressor, the inlet duct having a part of the duct adjoining the inlet of the compressor and having decreasing cross section in an air flow direction defining a high-velocity area in order to give the air flow a final velocity at the inlet to the compressor, the method comprising:
providing one or more spray nozzles positioned at the acceleration duct; and
introducing a spray of drops of cleaning fluid in the high-velocity area of the inlet duct, wherein the cleaning fluid is forced through the one or more spray nozzles and directed substantially parallel to and in the same direction as the direction of the air flow in order that the drops of the spray penetrate and stay in the air flow, to avoid leaving a liquid film within the high velocity area of the inlet duct, and the spray being introduced at a position in the duct section where the air velocity is a percentage of the final velocity at the compressor inlet.
15. A method of claim 14, wherein cleaning fluid is forced through the spray nozzle with a pressure drop that is dependent on the location of the nozzle, and with the pressure drop within the acceleration duct being greater than a pressure drop occurring in the inlet upstream of the acceleration duct so that the drops of the spray stay in the air flow instead of leaving a liquid film on the walls of the inlet duct.
16. A method of claim 15, wherein the drops of the spray have a mean size that is less than around 150 \u03bcm.
17. A method of claim 15, wherein the air velocity is at least 40 percent of the final velocity at the compressor inlet.
18. A method of claim 15, wherein the drops of the fluid spray acquire a slip ratio of at least 0.8 at the compressor inlet.
19. A method of claim 15, wherein the spray comprises a velocity within the range of about 100 ms to about 200 ms to enter the air flow and penetrate the compressor to wet and clean the rotating and fixed sections of the compressor and avoid substantial contact with the inlet structural supports.
20. A method of claim 14, wherein the drops contact a compressor blade and a compressor stator vane.
21. A method of claim 14, wherein the drops have a mean size that remains substantially constant between about 50 to about 150 \u03bcm.
22. A method of claim 14, wherein the turbine is rotated with the aid of a start motor.
23. A method of claim 14, wherein a fuel is burned in a combustion chamber of the gas turbine unit.
24. A system for cleaning a stationary gas turbine unit during operation, wherein the unit comprises:
a turbine;
a compressor driven by the turbine having an inlet; and
an air inlet duct arranged upstream of the compressor, the air inlet duct having an acceleration duct adjoining the inlet of the compressor, the acceleration duct having a decreasing cross section in an air flow direction in order to increase the velocity of the air moving through the acceleration duct, with the air flow having a final velocity at the inlet to the compressor; the system comprising:
one or more nozzles positioned in the acceleration duct;
the one or more nozzles having cleaning fluid forced there through in order to form a spray of drops that penetrate the air flow; and
the one or more nozzles directing the spray of drops in a direction substantially parallel to and in the same direction as the direction of the air flow, with the drops being carried by the air flow to contact one or more compressor blades for cleaning.
25. A system of claim 24, wherein the one or more nozzles are operated at a defined supply pressure to produce drops with mean size of around 50 to 150 \u03bcm.
26. A system of claim 24, wherein the one or more nozzles are operated at a defined supply pressure to produce a spray at a velocity within the range of about 100 ms to about 200 ms to allow injection into the compressor inlet air flow, wherein the spray enters the compressor inlet avoiding substantial contact with structural supports or boundaries of the inlet.
27. A system of claim 24, wherein the one or more nozzles are operated at a defined supply pressure to provide a spray with sufficient velocity within the range of about 100 ms to about 200 ms to enter the air flow and penetrate the compressor to wet and clean the rotating and fixed sections of the compressor.
28. A system of claim 27, wherein the cleaning fluid is forced through the spray nozzle with a pressure drop that is dependent on the location of the nozzle, and with the pressure drop within the acceleration duct being greater than a pressure drop occurring in the inlet upstream of the acceleration duct.
29. A system of claim 24, wherein the air inlet duct comprises a bell mouth and inner cone structure.
30. A system of claim 24, wherein the drops have a mean size that remains substantially constant between about 50 to about 150 \u03bcm.
31. A system of claim 24, wherein the turbine is rotated with the aid of a start motor.
32. A system of claim 24, wherein a fuel is burned in a combustion chamber of the gas turbine unit.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A path size control method for a cross-connecting device connected to an upstream side cross-connecting device via a first transmission line and to a downstream side cross-connecting device via a second transmission line so as to relay a communication frame received from the first transmission line to the second transmission line in a Synchronous Digital HierarchySynchronous Optical Network (SDHSONET) network, the method comprising the steps of:
detecting index information indicating a size of a path from H1 and H2 bytes of a header of a first communication frame received from the first transmission line;
setting new index information into H1 and H2 bytes of a header of a second communication frame to be transmitted to the second transmission line if the path size has been specified from a manager system of the network; and
setting the detected index information into the H1 and H2 bytes of the header of the second communication frame if the path size has not been specified from the manager system of the network.
2. A path size control method according to claim 1, further comprising the steps of:
designating the maximum bandwidth of the path previously from said manager system;
comparing the path size determined from the index information detected from the H1 and H2 bytes of said first communication frame with said maximum bandwidth; and
generating an alarm to be notified to said manager system when it is judged that the path size determined from the detected index information exceeds the maximum bandwidth.
3. A cross-connecting device connected to an upstream side cross-connecting device via a first transmission line and a downstream side cross-connecting device via a second transmission line so as to relay a communication frame received from the first transmission line to the second transmission line in a Synchronous Digital HierarchySynchronous Optical Network (SDHSONET) network, comprising:
a first port connected to the first transmission line to receive a first communication frame;
a second port connected to the second transmission line to transmit a second communication frame including data extracted from the first communication frame; and
a path size determination means for detecting index information indicating the size of a path from H1 and H2 bytes of a header of the first communication frame and for setting the detected index information into H1 and H2 bytes of a header of the second communication frame if the path size has not been specified from a manager system of the network.
4. A cross-connecting device according to claim 3, wherein said path size determination means is comprised of:
a memory for storing bandwidth information indicating the maximum bandwidth of the path designated from said manager system; and
means for comparing the path size determined from the index information detected from the H1 and H2 bytes of said first communication frame with said maximum bandwidth and for generating an alarm to be notified to said manager system when it is judged that the path size determined from the detected index information exceeds the maximum bandwidth.