THERMAL INSPECTION SYSTEM AND METHOD

• US 20090255332A1
• Filed: 04/11/2008
• Published: 10/15/2009
• Est. Priority Date: 04/11/2008
• Status: Active Grant

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Bunker, Ronald Scott, Nirmalan, Nirm Velumylum
• Granted Patent: US 7,909,507 B2
• Time in Patent Office: Days
• US Class Current: 73/204.110
• CPC Class Codes: G01F 1/68 by using thermal effects
• CPC Class Codes: G01K 17/00 Measuring quantity of heat measuring temperature by calorimetry G01K3/00 - G01K11/00; specially adapted for measuring thermal properties of materials, e.g. specific heat, heat of combustion G01N
• CPC Class Codes: G01K 17/20 across a radiating surface, combined with ascertainment of the heat transmission coefficient materials therefor G01K17/08

Abstract

A thermal inspection method is provided for a component comprising at least one complex internal passage arrangement defining at least one opening. The thermal inspection method includes flowing a fluid through the at least one complex internal passage arrangement. The fluid has an initial temperature that differs from an initial temperature of the component. The thermal inspection method further includes measuring a thermal response of the component to the fluid flow and analyzing the thermal response to determine a number of heat transfer coefficients {h_lmn} corresponding to respective locations {l,m,n} within the complex internal passage arrangement. The thermal inspection method further includes using the heat transfer coefficients {h_lmn} to determine at least one of (a) a flow rate through respective ones of the at least one opening, and (b) a cross-sectional area for respective ones of the at least one opening.

Claims

1. A thermal inspection method for a component comprising at least one complex internal passage arrangement defining at least one opening, the thermal inspection method comprising:

flowing a fluid through the at least one complex internal passage arrangement, wherein the fluid has an initial temperature that differs from an initial temperature of the component;

measuring a thermal response of the component to the fluid flow;

analyzing the thermal response to determine a plurality of heat transfer coefficients {h_lmn} corresponding to a respective plurality of locations {l,m,n} within the complex internal passage arrangement; and

using the heat transfer coefficients {h_lmn} to determine at least one of (a) a flow rate through respective ones of the at least one opening, and (b) a cross-sectional area for respective ones of the at least one opening.

2. The thermal inspection method of claim 1, wherein the measuring step comprises detecting at least one surface temperature, either directly or indirectly, of the component at a plurality of times.

3. The thermal inspection method of claim 2, wherein the detecting comprises obtaining a plurality of infrared images of the component.

4. The thermal inspection method of claim 1, comprising using the heat transfer coefficients to determine the flow rate through respective ones of the at least one opening by comparing the heat transfer coefficients {h_lmn} for the component with corresponding ones of a plurality of heat transfer coefficients {h^ref_lmn} for a reference part comprising at least one complex, internal passage arrangement defining at least one opening.

5. The thermal inspection method of claim 4, further comprising correlating the heat transfer coefficients {h^ref_lmn} for the reference part to a plurality of flow rate data.

6. The thermal inspection method of claim 1, comprising using the heat transfer coefficients to determine the cross-sectional area for respective ones of the at least one opening by comparing the heat transfer coefficients {h_lmn} for the component with corresponding ones of a plurality of heat transfer coefficients {h^ref_lmn} for a reference part.

7. The thermal inspection method of claim 6, further comprising correlating the heat transfer coefficients {h^ref_lmn} for the reference part to a plurality of cross-sectional area data.

8. The thermal inspection method of claim 1, further comprising:

repeating the flowing, measuring and analyzing steps for a plurality of similar components having at least one complex internal passage arrangement, with at least one opening, to generate a plurality of heat transfer coefficients {h′

_lmn} for the similar components; and

calculating a statistical measure {S_lnm} of the heat transfer coefficients {h′

_lmn} for the similar components, wherein a plurality of data used to calculate the statistical measure comprises at least one of a flow rate and a cross-sectional area for respective ones of the similar components,

wherein the using step comprises using the heat transfer coefficients to determine the flow rate through respective ones of the passages by comparing the heat transfer coefficients {h_lmn} for the component with the statistical measure {S_l,n,m}Of the heat transfer coefficients {h′

_lmn} for the similar components.

9. The thermal inspection method of claim 1, further comprising:

repeating the flowing, measuring and analyzing steps for a plurality of similar components having at least one complex internal passage arrangement, with at least one opening, to generate a plurality of heat transfer coefficients {h′

_lmn} for the similar components; and

calculating a statistical measure {S_lnm} of the heat transfer coefficients {h′

_lmn} for the similar components,

wherein the using step comprises using the heat transfer coefficients to determine the cross-sectional area for respective ones of the passages by comparing the heat transfer coefficients for the component with the statistical measure {S_lnm} of the heat transfer coefficients {h′

_lmn} for the similar components.

10. The thermal inspection method of claim 1, wherein said step of flowing the fluid induces a transient thermal response of the component, and wherein the measuring step comprises detecting at least one surface temperature, either directly or indirectly, of the component at a plurality of times.

11. The thermal inspection method of claim 1, wherein said step of flowing the fluid comprises providing a steady flow of fluid through the at least one complex internal passage arrangement, and wherein the measuring step comprises detecting at least one surface temperature, either directly or indirectly, of the component at a plurality of times

12. The thermal inspection method of claim 1, comprising using the heat transfer coefficients to determine the flow rate through respective ones of the at least one opening by solving an equation h=(k/D)CRe^mPrⁿ, where k is a thermal conductivity of the fluid, D is a hydraulic diameter of a connecting orifice, Re is the Reynolds number, Pr is the Prandtl number, and C, m and n are correlation constants.

13. The thermal inspection method of claim 1, comprising using the heat transfer coefficients to determine the cross-sectional area for respective ones of the at least one opening by solving an equation h=(k/D)CRe^mPrⁿ, where k is a thermal conductivity of the fluid, D is a hydraulic diameter of a connecting orifice, Re is the Reynolds number, Pr is the Prandtl number, and C, m and n are correlation constants.

14. A thermal inspection system for a component comprising at least one complex internal passage arrangement defining at least one opening, the thermal inspection system comprising:

a flow chamber configured to supply a fluid flow to the at least one complex internal passage arrangement;

a thermal monitoring device configured to detect a plurality of surface temperatures, either directly or indirectly, of the component at a plurality of times corresponding to a thermal response of the component to the fluid flow; and

a processor configured to;

analyze the thermal response to determine a plurality of heat transfer coefficients {h_lmn} corresponding to a respective plurality of locations {l,m,n} within the complex internal passage arrangement, and

use the heat transfer coefficients {h_lmn} to determine at least one of (a) a flow rate through respective ones of the at least one opening, and (b) a cross-sectional area for respective ones of the at least one opening.

15. The thermal inspection system of claim 14, wherein the thermal monitoring device comprises an infrared detector.

16. The thermal inspection system of claim 15, wherein the infrared detector comprises an infrared camera configured to capture a plurality of images corresponding to the thermal response of the component to the fluid flow.

17. The thermal inspection system of claim 14, further comprising a thermal source configured to heat or cool the component.

18. The thermal inspection system of claim 14, wherein the processor is configured to determine at least one of (a) the flow rate through respective ones of the at least one opening, and (b) the cross-sectional area for respective ones of the at least one opening, by comparing the heat transfer coefficients {h_lmn} for the component with corresponding ones of a plurality of heat transfer coefficients {h^ref_lmn} for a reference part comprising a complex, internal passage arrangement defining at least one opening.

19. The thermal inspection system of claim 14, wherein the processor is configured to determine at least one of (a) the flow rate through respective ones of the at least one opening, and (b) the cross-sectional area for respective ones of the at least one opening, by comparing the heat transfer coefficients {h_l,m,n} for the component with a statistical measure {S_l,n,m} of a plurality of heat transfer coefficients {h′

_lmn} for a plurality of similar components.

20. The thermal inspection system of claim 19, wherein the processor is further configured to calculate the statistical measure {S_lnm} of the heat transfer coefficients {h′

_lmn} for the similar components.

21. The thermal inspection system of claim 14, wherein said flow chamber is configured to supply a steady fluid flow to the at least one complex internal passage arrangement.

22. The thermal inspection system of claim 14, wherein said flow chamber is configured to supply the fluid flow to the at least one complex internal passage arrangement, such that the component exhibits a transient thermal response to the fluid flow.

23. The thermal inspection system of claim 14, wherein the processor is configured to determine at least one of (a) the flow rate through respective ones of the at least one opening, and (b) the cross-sectional area for respective ones of the at least one opening, by solving an equation h=(k/D)CRe^mPrⁿ, where k is a thermal conductivity of the fluid, D is a hydraulic diameter of a connecting orifice, Re is the Reynolds number, Pr is the Prandtl number, and C, m and n are correlation constants.