Thomas Bohdal

Hi, What does the primary secondary option in the Fans tool do?

Thank you this was helpful. I did this, and also compared with a hand-calculation comparing only strata heat and air free cooling. The scenarios are a) leave as is, b) completely open partial blockages to let more air through c) completely block partial blockages. The two methods show improvement in scenarios (b) and (c) but differ in which is the preferred of the two. This may be because my hand calculation ignores moisture. Providing results below for interest: Sigma Heat (caculated as per instruction above); option (b) is preferred. Case Sigma heat, kJ/kg a) Initial state 24.4 b) Partial blockages cleared entirely 23.3 c) Blockages hermetically sealed 24.3 Simplistic calculation of change in air and strata heat flow; option (c) is preferred. Case Change in Airflow m3/s Delta cooling power of incoming air, kW[1] Delta rate of heat flow from strata heat, kW Delta rate of heat flow, net of air and strata, kW a) Initial state - - - - b) Partial blockages cleared entirely +17 -340 +210 -130 c) Blockages hermetically sealed -11 +225 -508 -283 [1] Assuming air at 20°C, threshold at 26°C DB),

Hi, I have some questions on the heat summary in Ventsim Design: 1) What is the difference in heat summary between TOTAL HEAT SUMMARY, and HEAT ADDED TO NETWORK? (These appear to be the same in a model I am running) 2) What does exhaust heat difference mean exactly (ie: difference between what and what?) 3) I am exploring these outputs as I would like to know which of 2 different scenarios makes the mine hotter or cooler in a specific deep mine: a) adding more flow, which may absorb more strata heat, but also may remove more heat in the exhaust b) closing some airways, which should reduce the strata heat (as there is less strata exposed) There are too many airways to simply compare temperatures so I am looking at only the summary for airways with >0 flow. What is the best value in the heat summary to indicate that the mine is relatively hotter or cooler? regards,