| 摘要 |
<p>A performance monitor (20) generates a fouling factor (FF) which indicates the level of fouling of a heat exchanger (10) having a heat exchange surface area and through which passes a heat exchange medium having a known specific heat. Temperature transmitters (TT1, TT2, TT3) are utilised to obtain values for the input and output temperatures of the heat exchange medium as well as the temperature in the heat exchanger of a heat exchange fluid used to transfer heat to or from the heat exchange medium. Modules (30, 40, 50, 60) are used to generate values for an actual heat transfer coefficient (Uact) and a nominal heat transfer coefficient (Uava) in the heat exchanger (10) as a function of the temperatures, flow rate and constant parameters such as area and specific heat, for the heat exchanger (10). The actual heat transfer coefficient (Uact) is compared with the nominal or original heat transfer coefficient (Uava) to determine if there is any deterioration in the coefficients which reflects fouling of the heat exchanger. A simple ratio of the nominal to actual heat transfer coefficients is taken (61) as a measure of the fouling factor (FF).</p> |
