Sizing any \u71b1\u56de\u53ce\u30b7\u30b9\u30c6\u30e0<\/a> starts with the state of the air. Four properties define it:<\/p>\n A psychrometric chart plots these properties on one diagram. A point fixes DB, WB, W, RH and h at once. Engineers use it to read what happens when air is heated, cooled, humidified or dehumidified – exactly the processes a recovery core performs.<\/p>\n A practical approximation for moist-air enthalpy is:<\/p>\n Heat recovery moves \u30a8\u30f3\u30bf\u30eb\u30d4\u30fc<\/em>, not just temperature. A \u9855\u71b1\u30ed\u30fc\u30bf\u30fc<\/a> shifts the dry-bulb part; an enthalpy wheel shifts both. Reading the exhaust and supply states on the chart tells you how much energy is actually available and whether you need latent recovery at all.<\/p>\n DB vs WB – what is the difference?<\/strong> DB is the real air temperature; WB reflects both temperature and moisture and is the lowest temperature the air can reach by evaporative cooling.<\/p>\n Does low RH mean dry air in winter?<\/strong> Cold outdoor air can have low RH but very little absolute moisture (low W); it still needs humidification indoors for comfort.<\/p>\n\n
The psychrometric chart<\/h2>\n
h \u2248 1.006 x T + W x (2501 + 1.86 x T)<\/code> (kJ\/kg dry air, T in degC)<\/p>\nWhy recovery engineers must know this<\/h2>\n
Frequently asked questions<\/h2>\n