Calibration method and system for a dynamic combustor sensor

Abstract

In one embodiment, the invention is a pressure sensor calibration system comprising a pressure chamber in fluid communication with a pressure sensor to be calibrated, the chamber is pressurized to a static pressure level. An oscillating surface on a wall of the chamber imparts a rapid pressure fluctuation in the static pressure level of the chamber. These rapid pressure fluctuations in a high-static pressure level chamber are used to calibrate the pressure sensor.

1 . A sensor calibration system comprising: 
 a pressure chamber in fluid communication with a sensor to be calibrated, said chamber pressurized to a static pressure level, and    a piston moving cyclically within said chamber, said piston having a front surface moving cyclically within said chamber wherein said front surface imparts a rapid pressure fluctuation to the static pressure level of said chamber.    
   
   
       2 . A sensor calibration system as in  claim 1  wherein the static pressure level is at least 200 psi.  
   
   
       3 . A sensor calibration system as in  claim 1  wherein said chamber is in thermal communication with a heat source, and said heat source heats the chamber to at least 700° F.  
   
   
       4 . A sensor calibration system as in  claim 1  wherein said pressure chamber has a volume no greater than 1.8 inches cubed.  
   
   
       5 . A sensor calibration system as in  claim 1  wherein the rapid pressure fluctuation is at a selected frequency in a range of about 50 hertz (Hz) to about 3,200 Hz.  
   
   
       6 . A sensor calibration system as in  claim 1  wherein said piston comprises a front surface facing said chamber and said front surface further comprises a conical section.  
   
   
       7 . A sensor calibration system comprising: 
 a pressure chamber in fluid communication with a sensor to be calibrated, said chamber pressurized to a static pressure level;    a piston having a reciprocating surface defining a surface of said chamber, said reciprocating surface imparts a rapid pressure fluctuation to the static pressure level of said chamber.    
   
   
       8 . A sensor calibration system as in  claim 7  wherein the reciprocating surface is a front surface of the piston.  
   
   
       9 . A sensor calibration system as in  claim 7  wherein said static pressure level is at least 200 psi.  
   
   
       10 . A sensor calibration system as in  claim 7  wherein said chamber is in thermal communication with a heat source, and said heat source heats the chamber to at least 700° F.  
   
   
       11 . A sensor calibration system as in  claim 7  wherein said pressure chamber has a volume no greater than 1.8 inches cubed.  
   
   
       12 . A sensor calibration system as in  claim 7  wherein the rapid pressure fluctuation is at a selected frequency in a range of about 50 hertz (Hz) to about 3,200 Hz.  
   
   
       13 . A sensor calibration system as in  claim 7  wherein said reciprocating surface further comprises a conical section facing said chamber.  
   
   
       14 . A sensor calibration system as in  claim 7  wherein said reciprocating surface further comprises a conical section facing said chamber, and said conical section having a first surface adjacent a probe sensing surface position in the chamber and a second surface adjacent a calibration probe sensing surface position.  
   
   
       15 . A pressure sensor calibration system comprising: 
 a probe holder having a mount for a pressure sensor to be calibrated, said holder having an aperturein fluid communication with a pressure generator;    said pressure generator having a pressure chamber coupled to a steady source of high pressure gas to pressurize the chamber to a static pressure level, and    said pressure chamber having an reciprocating piston which dynamically varies the static pressure level in the chamber.    
   
   
       16 . A calibration system as in  claim 15  wherein the static pressure is at least 200 psi.  
   
   
       17 . A sensor calibration system as in  claim 15  wherein the piston reciprocates at a selected frequency in a range of about 50 hertz (Hz) to about 3,200 Hz.  
   
   
       18 . A calibration system as in  claim 15  wherein said pressure chamber is in thermal communication with a heat source, and said heat source heats the pressure chamber to at least 700° F.  
   
   
       19 . A calibration system as in  claim 15  wherein said pressure chamber has a volume no greater than 1.8 inches cubed.  
   
   
       20 . A method for calibrating a sensor using a calibration device having a probe holder and pressure generator comprising: 
 a. monitoring the sensor to be calibrated in the probe holder such that the transducer head of the sensor is in fluid communication with a pressure chamber in the pressure generator;    b. pressurizing the pressure chamber to a static pressure level,    c. reciprocating a piston in fluid communication with the pressure chamber to generate a dynamic pressure fluctuation on the pressure level in the pressure chamber;    d. sensing the pressure level in the pressure chamber, and    e. generating a signal by the sensor representing the dynamic pressure fluctuation in the chamber.    
   
   
       21 . A method as in  claim 20  wherein the pressure chamber is maintained at a static pressure of at least 200 psi.  
   
   
       22 . A method as in  claim 20  further comprising heating the pressure chamber to at least 700° F.  
   
   
       23 . A method as in  claim 20  wherein the piston reciprocates at a selected frequency in a range of about 50 hertz (Hz) to about 3,200 Hz.  
   
   
       24 . A pressure sensor calibration system comprising: 
 a probe holder further comprising a mount for a pressure sensor to be calibrated and a sensor chamber adjacent the mount, said sensor chamber having an inlet aperture to receive a high pressure gas from a steady source of the high pressure gas to pressurize the sensor chamber, and    a pressure chamber having a reciprocating piston to dynamically vary the gas pressure level in the pressure chamber, wherein a passage between said pressure chamber and said sensor chamber transmits dynamic pressure variations from the pressure chamber to the sensor chamber.    
   
   
       25 . A pressure sensor calibration system as in  claim 24  further comprising a gas discharge port in said pressure chamber through which flows the high pressure air from the sensor chamber via the pressure chamber.