A liquid-cooling heat dissipation system capable of regulating water quality includes a first liquid inlet, a first liquid outlet, a heat exchange unit, a sensation unit, a water quality regulating unit for containing and releasing an agent and a control unit. The heat exchange unit has a heat exchanger, a first pump and a mating opening connected with the water quality regulating unit. The sensation unit detects the pH value of a first working liquid and transmits a sensation signal to the control unit. The control unit compares the sensation signal with a preset pH value range to generate and transmit a comparison result to an external interface, whereby the water quality regulating unit is manually controlled to release the agent or not. Alternatively, according to the comparison result, the control unit automatically controls the water quality regulating unit to release the agent or not.

Methods of placing sensors in structures may involve placing first particles including a first material of the structure on or above a support surface. Second particles including a second, different material may be dispersed among the first particles at least within a transition region of the structure proximate to a location where a sensor is to be supported by the structure. A sensor may be placed in the location. The first particles of the first material may be fused to one another and to the second particles of the second material to form the structure with the sensor supported by the structure.

A method of predicting the temperature of a resistive heating element in a heating system is provided. The method includes obtaining resistance characteristics of resistive heating elements and compensating for variations in the resistance characteristics over a temperature regime. The resistance characteristics of the resistive heating element include, but are not limited to, inaccuracies in resistance measurements due to strain-induced resistance variations, variations in resistance due to the rate of cooling, shifts in power output due to exposure to temperature, resistance to temperature relationships, non-monotonic resistance to temperature relationships, system measurement errors, and combinations of resistance characteristics. The method includes interpreting and calibrating resistance characteristics based on a priori measurements and in situ measurements.

Embodiments of the invention are shown in the figures, where a system is presented for detecting a heat exchanger blockage, including: a heat exchanger and a bypass for the heat exchanger; a temperature sensor for measuring a temperature of a fluid downstream the heat exchanger; and a control system adapted to detect a bypass opening based on the measured fluid temperature, and to provide a signal indicating the bypass opening in response to the detection of the bypass opening.

A method for detecting a leak in a heat exchanger plate includes positioning the heat exchanger plate between a first fixture and a second fixture to create both a first sealed space between the heat exchanger plate and the first fixture and a second sealed space between the heat exchanger plate and the second fixture. The first sealed space is on one side of the heat exchanger plate and the second sealed space is on the other side of the heat exchanger plate. The method includes supplying an inert gas to the second sealed space, drawing a vacuum in the first sealed space, and detecting whether the first sealed space includes the inert gas. The presence of inert gas indicates the plate is not leak-tight.

Disclosed is a methodology for determination and prediction of heat exchanger fouling, such as polymer fouling in the circulation loop that forms part of the heat exchanger system. The buildup of a polymer or other undesired material deposit in the heat exchanger provides a distinctive temperature signature (thermal gradient) on the surface of the heat exchanger asset, which is visualized using a thermographic camera. Coupling images (thermograms) from the camera with a machine learning algorithm identifies fouling and, with knowledge of the historical data of the asset and operating and ambient conditions, enables prediction of future fouling. The thermal images provide several types, or orders, of temperature information that are indicative of locations vulnerable to fouling. In one case, the method uses machine learning applied to time-based temperature change/gradient information to detect hidden polymer fouling in areas that form part of the heat exchanger asset.

A built-in fault-detection-and-isolation (FDI) test for a system that has measurable input operating conditions and output parameters is designed. Inferential sensors, which are functional combinations of the input operating conditions and the output parameters, are evolved using genetic programming so as to be rich in information pertaining to fault conditions of the system. Simulations, based on a system model, of various combinations of the input operating conditions and the fault conditions are performed so as to provide simulated values of the inferential sensors and the output parameters. Sensitivities of the inferential sensors and the output parameters to the fault conditions and to system uncertainties are calculated. The inferential sensors are repeatedly evolved until a termination condition is achieved. The built-in test is designed based on a combination of a selected input operating condition and one or more of the inferential sensors and/or the output parameters.

A system and method for cleaning coils in a fired heater is provided. The cleaning system includes a data acquisition tool configured to pass through the coils to acquire data. The cleaning system is configured to establish a pre-cleaning fouling baseline derived from the data for the coils. The cleaning system is configured to develop an optimized cleaning plan for the coils based on the pre-cleaning fouling baseline. The optimized cleaning plan includes a focused cleaning for a fouling area in the coils. The cleaning system further includes at least one cleaning pig configured to clean the coils based on the optimized cleaning plan. The cleaning system further includes a decoking truck for cleaning the coils with the cleaning pig based on the optimized cleaning plan.

An air-conditioning apparatus includes a heat exchanger, a fan, and a controller. The heat exchanger causes heat exchange to be performed between a medium that transfers heat, and air. The fan sends air to the heat exchanger. The controller determines whether clogging due to foreign matter has occurred in the heat exchanger, based on a command voltage varying in accordance with the rotation speed of a fan motor that drives the fan.

A counter-flow simultaneous heat and mass exchange device is operated by directing flows of two fluids into a heat and mass exchange device at initial mass flow rates where ideal changes in total enthalpy rates of the two fluids are unequal. At least one of the following state variables in the fluids is measured: temperature, pressure and concentration, which together define the thermodynamic state of the two fluid streams at the points of entry to and exit from the device. The mass flow rate of at least one of the two fluids is changed such that the ideal change in total enthalpy rates of the two fluids through the device are brought closer to being equal.