What is parallel flow heat exchanger
The plate heat exchanger plates are divided into single-side flow and diagonal flow according to the flow pattern of the heat exchange medium. The parallel flow means that the heat exchange medium flowing from the right corner hole of the heat exchanger plate finally flows out from the right corner hole. Similarly, the heat exchange medium flowing from the left corner hole finally flows out from the left corner hole. In terms of heat transfer efficiency, the diagonal flow mode is superior to the single-sided flow, but the single-sided flow method is relatively low in cost, so in the case where the heat exchange efficiency can be satisfied, the single-sided flow form is adopted.
There is a phenomenon of uneven fluid distribution inside the heat exchanger. For a single-sided flow plate heat exchanger, the speed is much larger than the other side in the connections direction of the inlet and outlet, which also leads to uneven distribution of the heat exchange effect. Near the inlet section, due to the influence of the inlet section, the pressure in the direction of the inlet and outlet is greater than the other side. In the vicinity of the outlet section, the pressure in the direction of the inlet and outlet is smaller than the other side. The combination of Nu, pressure drop and viscous dissipation of the hard board combination is higher than that the soft board combination.The same angle of the hard plate combination is smaller than that the soft board combination, and the heat exchange effect is better. Nu and pressure drop and viscous dissipation increase with the increase of inlet flow rate, and the coordination angle does not change with the change of inlet flow rate.