Computational Fluid Dynamics Design And Analysis Of Forced Ventilation Temperature Sensor

The magnitude of air temperature change is in the order of 0.1?/10a. Due to solar radiation effect, current air temperature sensors inside a traditional radiation shield may produce a measurement error that is 0.8? or higher. To improve the observation accuracy, it is necessary to study the new temperature sensor.In this article, a forced ventilation temperature sensor is proposed. By using the method of computational fluid dynamics (CFD), the radiation error of the forced ventilation temperature sensor is solved. According to the simulation results, it is found that when the inlet diameter of the L-shaped radiation shield is 25 mm or more,the radiation error is obviously reduced. The radiation effect of stainless steel is better. The radius of curvature is proportional to the radiation error. On the basis of the study, solar radiation intensity, airflow speed, underlying surface reflectivity, the sun angle, altitude has carried on the thorough analysis by means of computational fluid dynamic, and found that the radiation error increases with increasing the solar radiation intensity, underlying surface reflectivity and altitude, and diminishes with increasing airflow speed. When the airflow speed air velocity is greater than 8 m/s,the solar radiation intensity, the underlying surface reflectivity, the sun angle have little effect on the radiation error, and the radiation error can be reduced to the order of 0.01?.The CFD results are fitted by a neural network algorithm method. Then, a radiation error correction equation is obtained. The results show that the difference between the CFD results and the results given by the radiation error correction equation is less than 0.006?. Finally, according to the correction method of the error of the forced ventilation temperature sensor measurement results, this paper writes error correction software of forced ventilation temperature sensor. In the practical application of forced ventilation temperature sensor, it can provide real-time error correction on the temperature measurement results.