How to maximize the optimal measurement location to maximize the sensitivity and signal ratio of the temperature sensor
We found that the easiest way to prevent PH electrode staining is to install it in a pipeline with a flow rate of 5 to 7 FPS, and we began to realize the importance of the measurement position, thereby preventing the response speed of 100 times. Caused by a few millimeters of coating. The higher speed also makes the electrode respond faster when cleaning. The traditional viewpoint of putting the electrode in the container is proven to be wrong in several aspects. Even the speed in the container with the highest level is only 1 FPS, resulting in a slow response and needed to remove the electrode more frequently. In addition, the electrode from the container used in use is more problematic than taking out from the isolation recycling pipeline.

We also found that the PH electrode noise that was too close to the exit of the installation of the static mixture was too noisy. Move the electrode downstream 25 pipe diameters to make the world different. Due to additional transmission delay (9 feet 4 -inch pipelines, 6 FPS), the deadline for the dead area has only increased by 1.5 seconds. The reduction of noise enables us to use smaller filtering time, so that the actual general ring road dead area time.

The same principle is suitable for thermocouple suite, but the effect is not so significant. Higher speed will reduce the scaling rate and reduce measuring lag, which is the result of the increase in heat transfer coefficient. (The circular gap (air gap) between the temperature sensor and the inner diameter of the thermocouple jacket is greater than the speed.) The thermocouple sleeve should also be located at about 25 times the diameter of the downstream of the thermal exchange to allow the fluid mixed with the tube Then, then, then

Drops in the bubbles and air flow in the liquid flow will produce noise when the impact temperature sensor. The bubbles produced by air, oxygen and carbon dioxide sprayer in biochemical reactors and chemical reactors can cause soluble oxygen and pH signals to become noisy. The water droplets at the exit of the thermostat will cause noise to measure the temperature. The ammonia bubble at the exit of the static mixture can cause no noise to measure the pH.

The tip of the electrode or thermocouple sleeve should be close to the centerline of the pipeline, because the temperature and ingredients change with the cross section of the pipeline. For high -stick fluids, errors are obvious. We found that due to the high viscosity of the polymer and the impact of 98% sulfuric acid, the temperature measurement of the extruder export and the pH value measurement of the static mixed exit with sulfuric acid reagents is particularly sensitive to the depth of the tip of the temperature sensor.

Differential pressure water head meters and vortex meters should be located in a place where the speed distribution is evenly distributed, the flow turbulence, and there is a single phase -or the pipe designer tells you anywhere (joking).

Concept: The location of the temperature sensor should provide sufficient stay time and mixing to ensure a single phase and uniform mixture. This position should minimize the volume between the injection point and the temperature sensor to minimize the delay. For different pressure heads and vortex schemes, consistent speed distribution is required. The most important thing is that this location must be sensitive to changes in the two directions.

Details: Maximum changes in interference and setting points during maximum testing. For ingredients, pH values, and temperature, select the position where the maximum changes are displayed in two directions to achieve the positive and negative change of the ratio of controlling flow to the inlet flow. Essence For the distillation tower, the best position of the thermometer sleeve is the tower with the largest temperature change to increase or reduce the ratio of the return and the distillation or the ratio of the steam to the distillation. Temperature or pH temperature sensors and analyzers should be close to the center of the pipeline, and should be extended through the equipment wall. A series of temperature sensors that crossed the fluidized bed at multiple vertical distances,

The insertion length of the thermal sleeve should be greater than 5 times the diameter of the thermal sleeve. To maximize the heat conduction error caused by the thermal conductivity, the error is the thermal conductivity carried out along the tube wall along the cutting -edge and the process connection. In order to prevent vibration failure in the tail current in the pipeline, the procedure provided by the manufacturer should be calculated to the maximum length of the allowed. The position with a good mixing and single -phase will minimize the fluctuations of the measurement temperature and concentration, and the bubbles or solid and solid droplets in the liquid or the pH temperature sensor or the sample pipeline of the analyzer or enter the pressure pulse into the pressure pulse Destruction and horizontal measurement caused by pipeline. The pressure probes in high -speed airflow and furnace must be designed to minimize dynamic and vacuum effects. The temperature sensor and sample probe should not be installed on the pump absorption entrance, but should be installed on the downstream of the filter. By reducing transportation delay and increased speed, the time and lag of temperature sensors are reduced to the maximum extent.

The transmission delay in the pipe or sampling pipeline is the volume divide by flow rate or distance. The lagging time of temperature and pH temperature sensors decreases with the increase of the heat transfer coefficient and the increase of the mass transmission coefficient, respectively as the speed increases. Dirt also decreases as the speed increases.

Note: The volume of the material volume of the material behind or the surface of the stirring container or near or near the bottom of the vessel may not be mixed in full. Filling and fluidized bed equipment may have uneven ingredients and temperature distribution due to flow channels. Vibration analysis procedures may only pay attention to thermal suite failure without predicting RTD failures. The use of calcium hydroxide (lime) or magnesium hydroxide as a reagent seems to have cost -effectiveness, unless you consider the cost of controlling poor control and solid entering the downstream.

Exception: Due to the height or obstacles, the best position may not be accessible or maintained.

Insight: The optimal measurement position can maximize the sensitivity of the temperature sensor, maximize the signal -to -noise ratio, and maximize the time to shorten the dead area.

Experience rules: Find a position that is sensitive to process changes, where the fluid has a uniform mixture and single -phase, and the temperature sensor lags behind and the transmission delay is the least.