is the efficiecy and the effectiveness of a heat exchanger the same thing. I know that to calculate the effectiveness of a heat exchanger, you use effectiveness=q/qmax where qmax=Cmin(T_h,i-T_c,i). Just wondering, do you calculate the efficiency in the same way.I'm doing this lab where we are required to calculate the heat absorbed as well as the heat emitted. then, we are required to calculate the efficiency. Is the efficiency the heat absorbed on heat emitted.any help would be appreciated.
that is a issue that calls for you to stability the change in temperature of both fluids with the quantity of warm temperature being transferred. You anticipate a set temperature differences for both fluids and calculate the quantity of warm temperature the exhanger can move with those temperatures. you also calculate the quantity of warm temperature needed to make that fluctuate to both fluids utilising their particular heats. At strong starting up aspect for a counter bypass exchanger can be a distinction between the inlet of the chilly water and the nice and comfortable oil of 10 to 5 ranges. decision this distinction till you get a warmth stability in both calculations.
Efficiency is the % heat *that particular unit* could recover. Effectiveness is the percent heat recovered compared with all the heat which could possibly be recovered from the outgoing stream of air. (e.g. from an infinitely large area exchanger)
Efficiency questions seem to be popping up quite a bit today... Efficiency is power out divided by power in, and since perpetual motion is thermodynamically impossible, is always less than one. Power in is simple if it's source is electrical, simply V*I for purely resistive loads. If there's a motor involved, don't forget that there will be an inductive component to it which will make the power in appear slightly higher than it actually is if you use V * I to calculate it - you must instead use a true watt meter which basically outputs the integral of instantaneous Vi * Ii. I don't know what your effectiveness variables represent, but what you need is the energy in joules over a period of time or power in watts of the heat removed/added from the object you are cooling/warming. That divided by power in is your efficiency.
Efficiency V Effectiveness
Not sure how your professor is defining terms but I assume one is the amount of heat (as a percent) that is removed from the fluid passing through the heat exchanger. The other is the amount of heat (as a percent of what is collected at the hot end of the heat exchanger) that is rejected to the heat sink at the cold end. Hope that helps.
