井筒水位预报的一种新方法

A NEW METHOD FOR PREDICTION OF WATER LEVEL IN SHAFT

数值法预报出抽水井处的水位是均衡域的平均值，它既不代表抽水井井壁水位，更不代表抽水井井筒水位。在数值法拟合、预报结果的基础上，若以抽水井处拟合水位与实抽水位之差作为由计算方法和井的作用共同产生的附加除深（△hf），以附加降深（△hf）与实际单井涌水量（Q实）之比作为附加降深系数（β）；多个抽水井时，可取其算术平均值作为平均附加降深系数（β），附加降深系数（β或β）与设计单井开采量（Q设）之积则是设计开采条件下抽水井的附加降深（△hf），再以抽水井处的预报水位（hj）减去该附加降深（△hf），便可得到抽水井井筒水位（hn）。

The water level of abstraction well to be predicted by means of numerical method is anaverage value in an isotatic regime. It represents neither sidewall water level of abstractionwell, nor that of well bore. Based on fitting and prediction results from numerical method,taking the difference between fitting level and real abstracted water level in an abstractionwell as the supplemental deep drawdown (△hf) co-produced by calculation and well function, and the ratio between the supplemental deep drawdown (△hf) and real outflow rate(Qr) of individual well as supplemental deep drawdown coefficient (β5); when pumping several wells the arithmetic mean can be taken as the averaged supplemental deep drawdown coefficient (β). The product of the supplemental deep drawdown (βer β)by designed pumping rate(Qd) of individual well is the supplemental deep drawdown (△hf) of abstraction well underdesigned production conditions. Then the prediction water level (hj)at abstraction well minusthe supplemental deep drawdown (△hf) can work out the water level of abstraction well bore(hn).