An apparatus for measuring a fouling resistance and a cleanliness factor of heat-transfer surface and which is capable of continuously and accurately monitoring a build-up degree of deposits on a heat-transfer surface of a heat exchanger includes a fouling sensor having a given length of metal wire wound inside the heat-transfer surface for measuring an average temperature of the heat-transfer surface, a direct current voltage supply member for supplying a voltage to a heating wire of the fouling sensor, an accurate resistance measuring member connected with a temperature measuring metal wire of the fouling sensor for measuring an electrical resistance of the metal wire, an inlet/outlet portion water temperature measuring member for measuring the temperatures of the inlet/outlet portions of the apparatus, a water flow rate measuring member, and a data calculation apparatus for computing a fouling resistance and a cleanliness factor of a heat-transfer surface.
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 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.
