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China has highly emphasized the research and operational application of numerical weather prediction. This paper determines the objective function parameters, such as CAPE and SRH, to apply an ensemble numerical prediction model in weather forecasting. Preprocessing and evaluating rainfall data is necessary to construct the WRF-ARW numerical weather prediction model. The WRF-ARW model is applied to simulate the weather forecasts in Henan Province, and the difficulties and challenges faced in the efficient implementation of the parameterized scheme are outlined. The WRFARW model’s prediction errors for the maximum rainfall and total rainfall in Henan Province range from 1.78%-13.51% and 0.16%-3.78%, respectively, which are significantly less than 15%, and the model is more predictive than the others. The raw data test set’s credibility ranges from 0.957 to 0.997, which is close to 1, indicating that the raw data collected in this paper are highly credible. The WRF-ARW model’s qualification rates for forecasting maximum rainfall and total rainfall are 86.7% and 93.3%, respectively, and its overall accuracy is grade B and grade A, respectively. The pass rates for the peak occurrence time of maximum rainfall and total rainfall were 93.3% and 86.7%, respectively, and the overall prediction accuracy was Grade A and Grade B, respectively. The WRF-ARW model is effective in weather forecasting throughout Henan Province. In summary, the WRF-ARW model is very effective in improving the efficiency of ensemble numerical weather prediction and parameterization schemes in Henan Province.

A method of extracting exhaust waste heat and heating inlet wellhead by glycol wall heat exchange technology is proposed. Calculation and system design of exhaust air waste heat based on heat balance theory, combined with the actual case of Ningxia Yindonggou Coal Mine project, the Threlkeld enthalpy difference method was used to develop an analytical model for single tube heat transfer under wet conditions and to optimize the operating conditions. The results show that the glycol inter-wall heat transfer technology can extract the heat from the mine return air and meet the heat load required to prevent freezing at the wellhead. The system operates stably when the inlet temperature of the heat transfer medium in the tube is -2 ℃ and the flow rate is 1.49 m/s to 2.76 m/s. When the outdoor temperature is below -15 ℃, the wellhead temperature can still reach above 5 ℃.

The variable conductance heat pipe(VCHP) is used to solve the problem of uncontrollable heat exchange of heat pipe for waste heat recovery of mine return air. Considering non-condensable gas (NCG) and the phase change heat transfer process in the heat pipe, the one-dimensional heat transfer analysis model of a single heat pipe was established, and the heat transfer analysis of the heat pipe was conducted. The results show that the heat transfer effect of the VCHP with NCG reservoir at steady temperature is mainly determined by the temperature of the heat source and the working temperature in the VCHP. The regulating temperature range of the VCHP on the mine return air increases with the increase of the temperature difference between the mine return air and the fresh air. The operating temperature in the VCHP is basically constant during the regulation stage.