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US 5,248,198 AGranted
Method and apparatus for evaluating heat exchanger efficiency
OwnerThomas F. Droegeinventor
Life of this patent
Estimating the term…
Abstract
This invention is a method for evaluating the type, extent, and threshold of fouling in a heat exchanger test tube by using a reference test block to measure a reference thermal relaxation time at a guaranteed clean reference section of a heat exchanger test tube and comparing the reference thermal relaxation time with thermal relaxation times measured at unclean sections of the heat exchanger test tube.
Claims18
A method for evaluating fouling in a heat exchanger test tube containing a flowing fluid comprising the steps of:
- a. contacting a first test block including a heater and a thermometer with an exterior dimension of the test tube corresponding to a portion of the test tube having a clean inner dimension;
- b. measuring a reference thermal relaxation time by heating the reference test block with the heater to a temperature above that of the flowing fluid, discontinuing the heating and measuring the time it takes for the reference test block to cool from predetermined temperature, T1, to predetermined temperature T2;
- c. contacting a plurality of measuring test blocks each including a heater and a thermometer with an exterior dimension of the test tube corresponding to a portion of the test tube having an unclean inner dimension;
- d. heating the plurality of measuring test blocks such that each of the plurality of measuring test blocks is at a different temperatures, and all measuring test blocks are at a temperature greater than the temperature of the flowing fluid;
- e. maintaining the temperature of the plurality of measuring test blocks of step (d);
- f. measuring a thermal relaxation time for each of the plurality of measuring test blocks by discontinuing the heating to each of the plurality of measuring test block and measuring the time it takes for each of the plurality of measuring test blocks to cool from predetermined temperature, T1, to predetermined temperature T2;
- and
- g. repeating steps (d)-(f).
5 more elements
A method for evaluating fouling in a heat exchanger test tube containing a flowing fluid comprising the steps of:
- a. cleaning a section of an inner dimension of the test tube to define a clean reference section;
- b. contacting a reference test block including a heater and a thermometer with an exterior dimension of the test tube corresponding to clean reference section;
- c. measuring a reference thermal relaxation time by heating the reference test block with the heater to a temperature greater than that of the fluid passing through the test tube, discontinuing the heating of the reference test block, and measuring the time it takes for the reference test block to cool from predetermined temperature, T1, to predetermined temperature T2;
- d. contacting a first measuring test block including a heater and a thermometer with a top exterior dimension of the test tube corresponding to a portion of the test tube having an unclean inner dimension;
- e. contacting a second measuring test block including a heater and a thermometer with a bottom exterior dimension of the uncleaned test tube corresponding to the portion of the test tube having an unclean inner dimension;
- f. measuring a first thermal relaxation time corresponding to the top dimension of the unclean section of the test tube and a second thermal relaxation time corresponding to the bottom dimension of the unclean portion of the test tube;
- and
- g. determining the degree of fouling at the top dimension of the unclean portion of the test tube and at the bottom dimension of the unclean portion of the test tube.
5 more elements
A method for evaluating fouling in a heat exchanger test tube containing a flowing fluid comprising the steps of:
- a. contacting a reference test block including a heater and a thermometer with an exterior dimension of the test tube corresponding to a clean reference section of the test tube having a clean inner dimension;
- b. measuring a reference thermal relaxation time by heating the reference test block with the heater to a temperature greater than that of the fluid passing through the test tube, discontinuing the heating of the reference test block, and measuring the time it takes for the reference test block to cool from predetermined temperature, T1, to predetermined temperature T2;
- c. contacting a measuring test block including a heater and a thermometer with an exterior dimension of the test tube corresponding to a portion of the test tube having an unclean inner dimension;
- d. measuring the thermal relaxation time of the unclean section of the test tube by heating the measuring test block with the heater to a temperature greater than that of the fluid passing through the test tube, discontinuing the heating of the reference test block, and measuring the time it takes for the reference test block to cool from predetermined temperature, T1, to predetermined temperature T2;
- and
- e. determining the degree of fouling in the unclean section of the test tube.
3 more elements
Dependencies are inferred from the claim text.