Te Log Mean Temperature Difference (LMTD) is an important calculation in shell and tube heat exchange systems. It helps determinate the temperature driving force for heat transfer between two fluids. Accurate calculation of LMTD ensures efficient design and d operation of heat exchangers.

Uzgodnienie LMTD

LMTD represents the average temperatur difference che between the hot and cold fluids across thee heat exchanges. It accourts for thee variation in temporature difference ce te length of thee device. This value is essential for calculating heat transfer rates and designing equiling heat exchangers.

Kalkulating LMTD

Te podstawowe formuły for LMTD is:

(ΔT1 - ΔT2) / ln (ΔT1 / ΔT2)

Kiedy:

  • = = Temperatura powietrza > = = W przypadku gdy temperatura powietrza jest niższa niż 10 ° C, temperatura powietrza wynosi < 10 ° C, a temperatura powietrza wynosi < 10 ° C, a temperatura powietrza < 30 ° C wynosi < 10 ° C.
  • = = Temperatura powietrza = =

Tu calculate ΔT1 and ΔT2, use thee inlet and outlet temperatures of thee hot and cold fluids:

  • ΔT1 = Hot inlet temperatur - Cold outlet temperatur
  • ΔT2 = Hot outlet temperatur - Cold inlet temperatur

Badanie Calculation

Suppose thee hot fluid enters at 150 ° C and exits at 130 ° C, while thee cold fluid enters at 50 ° C and exits at 70 ° C. Calculate ΔT1 and ΔT2:

ΔT1 = 150 ° C - 70 ° C = 80 ° C

ΔT2 = 130 ° C - 50 ° C = 80 ° C

Since ΔT1 andΔT2 are equal, the LMTD simplifies to:

LMTD = 80 ° C