高低溫試驗箱箱內(nèi)空氣循環(huán)設(shè)計要求
1.高低溫試驗箱對由于尺寸大或者高散熱而不能使用自由空氣條件試驗箱試驗的試驗樣品，應(yīng)使用帶空氣流動（有強(qiáng)迫空氣循環(huán)）的試驗箱，除有關(guān)試驗箱尺寸以外，對自由空氣試驗箱的其他所有要求，有強(qiáng)迫空氣循環(huán)試驗箱的設(shè)備均適用。
1 high low temperature test box due to the large size and high heat dissipation and free air condition test chamber test cannot use a test sample, should be used with air flow (forced air circulation) test box, except relevant test box size, the free air chamber of the other requirements, forced air circulation chamber the equipment is applicable.
2.速度應(yīng)符合這樣的要求：不應(yīng)太小，以保證高低溫試驗箱試驗樣品在試驗時不致過熱，有不應(yīng)太大，以致試驗樣品在試驗時出現(xiàn)過冷，但是，盡管順暢地變得氣流的速度是有利的，然而在實踐中業(yè)已發(fā)現(xiàn)，采用0.5m/s的風(fēng)速是一種較好的折衷方案。
2 speed shall comply with such requirements: should not be too small, so as to ensure the high low temperature test box test sample is not overheating in the test, there should not be too large, so that the test sample in the trial when cold, but, although smoothly become airflow velocity is favorable, however it has been found that in practice, the wind speed by 0.5m/s is a good compromise.
3.宜盡可能均勻一致，氣流方向宜垂直向上，以將由上面對流所引起的氣流變化縮減到最低限度，如果風(fēng)扇在前箱產(chǎn)生正壓，然后使空氣從前箱經(jīng)過過濾器（如玻璃纖維欄網(wǎng)）逸出，則可得到均勻的氣流，在前箱還可裝設(shè)幾個控制該高低溫試驗箱溫度的加熱器，或者，利用把加熱器和過濾器的作用結(jié)合在一起的網(wǎng)狀加熱器。
3 should be as uniform as possible, the airflow direction is vertical, to cut the air caused by the convection of the above to a minimum, if the fan to generate positive pressure in the first box, and then make the air once box through the filter (such as glass fiber nets) to escape, then can get the flow evenly, heater, in the front box installed several control the high low temperature test box temperature can be or, to use the heater and a filter role together with mesh heater.
