An electro-mechanical, dual tube and plug device for on-line monitoring of performance losses due to reduced conductivity of a non condensing heat exchanger resulting from micro-bio fouling of the surfaces of said heat exchanger and for detecting change of heat transfer resistance of individual heat transfer tubes. The dual tube and plug assembly includes a first flow assembly tube and a second temperature assembly tube attached to the discharge end of a heat exchanger for providing accurate measurement of temperature and cooling water flow. The first flow assembly tube includes a tube having an inner chamber, including a flow sensor a temperature sensor for measuring discharge water temperature. The second temperature assembly tube plugs the inlet and the outlet of a heat transfer tube immediately adjacent to the flow assembly tube and includes a plurality of temperature sensors in the plugged empty heat transfer tube. Flow and discharge temperature signals from a first dual tube device are combined with other flow and discharge temperature signals, from additional dual tube devices. These signals are sent to a micro-processor which, utilizing inlet water temperature data provided by an inlet temperature sensor, continuously calculates, records and displays the individual heat transfer tube heat transfer co-efficient.
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part of U.S. patent application Ser. No. 08/165,750 filed Dec. 10, 1993, now U.S. Pat. No. 5,429,178, entitled Dual Tube Fouling Monitor and Method, the original application and of PCT patent application Ser. No. PCT/US94/14261, filed Dec. 12, 1994, entitled Dual Tube Fouling Monitor and Method which is incorporated herein by reference in it's entirety.
The present invention is directed to a system and method for monitoring the performance of a heat exchanger. In accordance with the system and method, baseline values of a performance factor (E) for baseline sets of heat exchanger operating values are calculated and stored. A current value of E is calculated for a current set of the operating values and is compared to a retrieved baseline value of E for a baseline set of the operating values that at least substantially matches the current set of the operating values. E provides a measure of the performance of the heat exchanger and is calculated using differential temperatures across the heat exchanger and without using any information concerning the physical construction of the heat exchanger.
A monitoring apparatus (1) for monitoring soil build-up in a pipe (6) which may form part of a pipework system including a heat exchanger. The pipework system is used in e.g. the heat treatment of milk and milk products. The monitoring apparatus (1) is in thermal connection with the pipe (6) and includes a body (2) capable of being heated by a heater. The power supplied to the heater is controlled and monitored such that a change in power input to the heater is indicative of a change in heat transfer to a fluid (8) flowing through the pipe (6). The heat from the apparatus (1) causes localized soil build-up in a portion of the pipe (6) near to the heated body (2). The soil build-up is representative of the soil build-up in the heat exchanger. The cleaning of the pipe (6) may be based on the soil build-up indicated by the monitoring apparatus (1).
A technique is disclosed for evaluating and monitoring performance of a heat exchanger system. Operating parameters of the system are monitored and fouling factors for heat transfer surfaces of the exchanger are determined. Trending of fouling may be performed over time based upon the fouling factors, and a model of fouling may be selected from known sets of models, or a model may be developed or refined. Fluid treatment, such as water treatment regimes may be taken into account in evaluation of fouling. An automated knowledge based analysis algorithm may diagnose possible caused of fouling based upon sensed and observed parameters and conditions. Corrective actions may be suggested and the system controlled to reduce, avoid or correct for detected fouling.
A system for calculating the degree of fouling in a heat exchanger having at least one longitudinal tube inside of a shell, the shell having a first heat exchange medium flowing inside the tube and a second heat exchange medium flowing across the outside surface of the tube. The apparatus includes a first temperature sensor, a device for determining the temperature of the tube at a first axial position of the tube, and a fouling detector. The first temperature sensor senses the temperature of the tube at a first axial position of the tube. The fouling detector calculates the degree of fouling in the tube based on the initial temperature difference between the temperature of the tube and the temperature of the first heat exchange medium in the tube at the first axial position, and a later temperature difference between the temperature of a surface of the tube and the temperature of the first heat exchange medium in the tube at the first axial position.
A system for isolating effects of one or more process parameters on performance of a heat transfer device is provided. The system includes an efficiency correction unit that is adapted to receive data from the heat transfer device. The data is representative of one or more measurable process parameters or a change in the one or more measurable process parameters of the heat transfer device. The efficiency correction unit is also configured to compute a normalized efficiency of the heat transfer device. The normalized efficiency represents a corrected efficiency that isolates effects of one or more process parameters on performance of the heat transfer device.
