Design & Sizing第 18 / 110 题
Using the rational method Q = 0.0104 x A x i, where A is the projected roof area in square feet and i is the rainfall rate in in/hr, what is the design storm flow for a 6,000 ft^2 roof at a 3 in/hr rainfall rate?
a.62 gpm
b.187 gpm
c.124 gpm
d.312 gpm
解析
Q = 0.0104 x 6,000 x 3 = 187 gpm. The 0.0104 factor converts one inch per hour of rain over one square foot into gpm. This design flow is then read against the vertical leader and horizontal storm-drain tables to size the conductors.
法律依据: UPC §1101.0免费刷完整 110 道题库 — 无需注册。
同考点相关题目
- A house has three natural-gas appliances: a 100,000 BTU/hr furnace, a 40,000 BTU/hr water heater, and a 65,000 BTU/hr range. Using 1,000 BTU per cubic foot, what total cfh must the gas meter and main serve?
- A propane appliance is rated at 150,000 BTU/hr. Propane has a heating value of about 2,500 BTU per cubic foot. What is the required gas flow in cfh?
- A gas branch must deliver 55 cfh of natural gas over a 60 ft longest length. The sizing table for that length gives these capacities: 1/2 in = 42 cfh, 3/4 in = 88 cfh, 1 in = 165 cfh. What is the minimum pipe size?
- A roof drains 4,800 ft^2 at a design rainfall rate of 4 in/hr. Using Q = 0.0104 x A x i, what is the storm design flow?
- A storm sizing table is published at 4 in/hr. A vertical leader lists a capacity of 4,600 ft^2 of roof at 4 in/hr. If the local design rate is only 2 in/hr, what roof area can that same leader serve?
- A booster pump must deliver 40 gpm and raise pressure by 45 psi. Using approximate water horsepower WHP = (gpm x psi) / 1,714, what is the water horsepower required (before pump efficiency)?