diff --git a/src/main/java/com/gunshi/project/hsz/service/StZvarlBService.java b/src/main/java/com/gunshi/project/hsz/service/StZvarlBService.java
index 6f68c87..5f979c1 100644
--- a/src/main/java/com/gunshi/project/hsz/service/StZvarlBService.java
+++ b/src/main/java/com/gunshi/project/hsz/service/StZvarlBService.java
@@ -2,6 +2,7 @@ package com.gunshi.project.hsz.service;
 
 import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
 import com.gunshi.project.hsz.mapper.StZvarlBMapper;
+import com.gunshi.project.hsz.model.StZqrlB;
 import com.gunshi.project.hsz.model.StZvarlB;
 import lombok.extern.slf4j.Slf4j;
 import org.springframework.stereotype.Service;
@@ -72,6 +73,90 @@ public class StZvarlBService extends ServiceImpl<StZvarlBMapper, StZvarlB> {
                 .collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue));
     }
 
+    /**
+     * 分段线性计算水位->库容
+     * 首先需要保证 水位->库容的数据要按水位从小到大进行排列
+     * @param zvarlBS
+     * @param rz
+     * @return
+     */
+    public BigDecimal getWByZvarl(List<StZvarlB> zvarlBS, BigDecimal rz) {
+        // 1. 参数校验
+        if (zvarlBS == null || zvarlBS.isEmpty()) {
+            throw new IllegalArgumentException("水位-库容关系列表不能为空");
+        }
+        if (rz == null) {
+            throw new IllegalArgumentException("水位值不能为空");
+        }
+        // 2. 检查边界情况：如果目标水位低于最低水位或高于最高水位
+        BigDecimal minRz = zvarlBS.get(0).getRz();
+        BigDecimal maxRz = zvarlBS.get(zvarlBS.size() - 1).getRz();
+        if (rz.compareTo(minRz) < 0) {
+            // 低于最低水位，可以选择抛出异常或进行外推（这里选择抛出异常）
+            return BigDecimal.ZERO;
+        }
+        if (rz.compareTo(maxRz) > 0) {
+            // 高于最高水位，可以选择抛出异常或进行外推（这里选择抛出异常）
+            return BigDecimal.ZERO;
+        }
+        int l = 0;
+        int r = zvarlBS.size() -1;
+        //二分查找 由线性On时间复杂度降为Ologn
+        while (l <= r) {
+            int mid = l + (r-l) / 2;
+            BigDecimal midRz = zvarlBS.get(mid).getRz();
+            int compareResult = midRz.compareTo(rz);
+            if(compareResult == 0 ){
+                return zvarlBS.get(mid).getW();
+            }else if(compareResult < 0){
+                l = mid + 1;
+            }else{
+                r = mid - 1;
+            }
+        }
+
+        /**
+         * 此时  l 指向第一个大于rz的位置
+         *      r 指向最后一个小于rz的位置
+         *      既  r为  x1 y1
+         *         l为   x2  y2
+         */
+        if(l < 0 || r >= zvarlBS.size()){
+            return BigDecimal.ZERO;
+        }
+        //获取前后差值的点
+        StZvarlB lowerPoint = zvarlBS.get(r);
+        StZvarlB upperPoint = zvarlBS.get(l);
+        return linearInterpolation(lowerPoint.getRz(),lowerPoint.getW(),upperPoint.getRz(),upperPoint.getW(),rz).setScale(3);
+    }
+
+
+    /**
+     * 线性插值辅助方法
+     * @param x1 已知点1的水位
+     * @param y1 已知点1的库容
+     * @param x2 已知点2的水位
+     * @param y2 已知点2的库容
+     * @param x  目标水位
+     * @return 目标水位对应的库容
+     */
+    private BigDecimal linearInterpolation(BigDecimal x1, BigDecimal y1,
+                                           BigDecimal x2, BigDecimal y2,
+                                           BigDecimal x) {
+        // 使用公式: y = y1 + ( (y2 - y1) / (x2 - x1) ) * (x - x1)
+
+        // 计算斜率: (y2 - y1) / (x2 - x1)
+        BigDecimal slope = y2.subtract(y1)
+                .divide(x2.subtract(x1), 10, RoundingMode.HALF_UP);
+
+        // 计算: slope * (x - x1)
+        BigDecimal xDiff = x.subtract(x1);
+        BigDecimal product = slope.multiply(xDiff);
+
+        // 计算最终结果: y1 + product
+        return y1.add(product);
+    }
+
 }