Tube heat exchanger area
Thread Content
It is known that a floating-head shell and tube heat exchanger can exchange 1.89×109 joules of heat per hour (approximately 525 kW). What is its approximate heat exchange area, and how can it be calculated?
The original poster needs to provide information on the medium conditions, as well as the inlet and outlet temperatures of the hot and cold fluids, before an estimation can be made.
The conditions you provided are incomplete; the overall heat transfer coefficient of the tubes and the temperature difference across the tubes are missing. Heat exchanger area = Total heat transfer rate / (Total heat transfer coefficient of the tubes * Temperature difference)
......... The heat load has been given as A=Q/KT, where T is the so-called average temperature difference; T=｛｝×coefficient. The coefficient needs to be looked up in a table: if it is higher than 0.8, the actual value is used; if it is lower than 0.8, 0.8 is used. The coefficients require two parameters to be determined: P = (t2 – t1) / (T1 – t2), and R = (T1 – T2) / (t2 – t1). T1 is the temperature at the hot flow inlet, t1 is the temperature at the cold flow inlet, t2 is the temperature at the cold flow outlet, and T2 is the temperature at the hot flow outlet. That’s about it; you need to plug the values into the formula to find it yourself. When calculating, the units must be consistent. Q=kj/h, K=W/m^2•℃, but when substituting these values, the Q value needs to be multiplied by 1000. PS: 1. If you don’t want to do the calculations, since the heat load values are already available, it’s still possible to determine the heat exchange area: lol 2. You can seek help in the technical discussion forum for heat exchange equipment – after all, those people specialize in this field, so their opinions should be more authoritative. . This post was last edited by Nine Heavens is me on 2009-2-25 22:49.]
Calculate the effective logarithmic mean temperature difference, select empirical heat transfer coefficients based on the fluids in the tube side and shell side, and the approximate heat exchange area can be obtained by using heat load/logarithmic mean temperature difference/emperical heat transfer coefficient
It is necessary to know the inlet and outlet temperatures of the hot and cold fluids, calculate the logarithmic mean temperature difference, and apply temperature difference corrections based on the tube-side and shell-side configuration. Then, based on the properties of the hot and cold media, flow velocity, etc., the heat transfer coefficient is calculated in order to determine the heat transfer area.