[Production Version] Daily Question 2018-2-28 (Short Answer)
Thread Content
Why is counterflow commonly used in heat exchangers? In a heat exchanger, the average temperature difference for heat transfer determines the amount of heat transferred. Among counterflow, co-current, and cross-flow configurations, counterflow heat exchangers have the largest average temperature difference; therefore, unless there are special circumstances, counterflow is the preferred configuration for heat exchangers.
In heat exchangers, the average linear temperature difference for heat transfer indicates the amount of heat transferred. As per the heat transfer formula Q=KA(ΔTm), a larger ΔTm results in greater heat transfer quantity. Among counterflow, co-flow, and cross-flow heat exchangers, those with counterflow configuration have the highest average temperature difference; therefore, unless there are special circumstances, counterflow design is commonly used in heat exchangers.
To improve heat transfer efficiency, among counterflow, co-flow, and cross-flow configurations, the counterflow heat exchanger has the largest average temperature difference
1. Under the same heat transfer surface conditions, the amount of heating agent (coolant) required in counterflow operation is less than that in coflow operation； 2. Under the same condition of heating agent (coolant) dosage, the heat transfer area of a counterflow heat exchanger is smaller than that of a coflow heat exchanger ； 3. When flowing in the same direction, the outlet temperature of the hot fluid is always lower than that of the cold fluid; therefore, when flowing in opposite directions, the temperature difference between the hot and cold fluids is larger and more uniform ； 4. The operating costs for counterflow operation are lower than those for forward flow
1. Under the same heat transfer surface conditions, the amount of heating agent (coolant) required in counterflow operation is less than that in coflow operation； 2. Under the same condition of heating agent (coolant) dosage, the heat transfer area of a counterflow heat exchanger is smaller than that of a coflow heat exchanger ； 3. When flowing in the same direction, the outlet temperature of the hot fluid is always lower than that of the cold fluid; therefore, when flowing in opposite directions, the temperature difference between the hot and cold fluids is larger and more uniform ； 4. The operating costs for counterflow operation are lower than those for forward flow.
In heat exchangers, the average temperature difference for heat transfer determines the amount of heat transferred. Among counterflow, co-current, and cross-flow configurations, the counterflow heat exchanger has the largest average temperature difference; therefore, unless there are special circumstances, counterflow is the commonly used configuration in heat exchangers
In heat exchangers, the average linear temperature difference for heat transfer indicates the amount of heat transferred. As per the heat transfer formula Q=KA(ΔTm), a larger ΔTm results in greater heat transfer quantity. Among counterflow, co-flow, and cross-flow heat exchangers, those with counterflow configuration have the highest average temperature difference; therefore, unless there are special circumstances, counterflow design is commonly used in heat exchangers.
It provides excellent counterflow heat exchange, resulting in more thorough heat transfer
In heat exchangers, the average temperature difference across the heat transfer surface determines the amount of heat transferred. Among counterflow, co-current, and cross-flow heat exchangers, those with counterflow configuration have the largest average temperature difference; therefore, unless there are special reasons, counterflow is the preferred arrangement for heat exchangers.
In heat exchangers, the average temperature difference for heat transfer indicates the amount of heat transferred. Among counterflow, coflow, and cross-flow configurations, the counterflow heat exchanger has the largest average temperature difference; therefore, unless there are special circumstances, counterflow is the commonly used configuration in heat exchangers.