Design & Sizing第 14 / 110 题
A natural-gas furnace is rated at 120,000 BTU/hr. Natural gas has a heating value of about 1,000 BTU per cubic foot. What gas volume flow, in cubic feet per hour (cfh), must the piping deliver?
a.12 cfh
b.120 cfh
c.60 cfh
d.1,200 cfh
解析
cfh = BTU/hr load / heating value = 120,000 / 1,000 = 120 cfh. Because natural gas is roughly 1,000 BTU per cubic foot, the cfh figure is simply the input in thousands of BTU. This cfh value is what you carry into the gas-pipe sizing table with the longest run.
法律依据: UPC §610.0免费刷完整 110 道题库 — 无需注册。
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