Design method for pumping chamber of water pump and water pump

The invention relates to a water pump pumping chamber design method and a water pump. The water pump pumping chamber design method comprises the following steps that the outer diameter D2 of an impeller and the width b2 of an impeller outlet are calculated according to the design flow Qd, the design lift H and the design rotating speed n of the water pump; according to the formula D3 = d2 * D2, the base circle radius D3 of the pumping chamber of the water pump is determined, in the formula, d2 is a base circle coefficient, and the range of d2 is 1.15-1.25; the inlet width b3 of the pumping chamber of the water pump is determined according to the formula b3 = a * b2, and in the formula, a is an inlet width coefficient and ranges from 2.5 to 3. According to the water pump obtained through the design method, the strength of dynamic and static interference between the impeller and the pumping chamber can be effectively reduced by increasing the base circle radius D3 of the pumping chamber of the water pump, then