{"id":293509,"date":"2024-10-19T19:56:35","date_gmt":"2024-10-19T19:56:35","guid":{"rendered":"https:\/\/pdfstandards.shop\/product\/uncategorized\/bs-iso-43772012\/"},"modified":"2024-10-25T17:07:42","modified_gmt":"2024-10-25T17:07:42","slug":"bs-iso-43772012","status":"publish","type":"product","link":"https:\/\/pdfstandards.shop\/product\/publishers\/bsi\/bs-iso-43772012\/","title":{"rendered":"BS ISO 4377:2012"},"content":{"rendered":"

This International Standard describes the methods of measurement of flow in rivers and artificial channels under steady or slowly varying conditions using flat-V weirs (see Figure 1).<\/p>\n

Annex A gives guidance on acceptable velocity distribution.<\/p>\n

PDF Catalog<\/h4>\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
PDF Pages<\/th>\nPDF Title<\/th>\n<\/tr>\n
9<\/td>\n1 Scope
2 Normative references <\/td>\n<\/tr>\n
10<\/td>\n3 Terms and definitions <\/td>\n<\/tr>\n
11<\/td>\n4 Symbols <\/td>\n<\/tr>\n
12<\/td>\n5 Characteristics of flat-V weirs
6 Installation
6.1 Selection of site <\/td>\n<\/tr>\n
15<\/td>\n6.2 Installation conditions
6.2.1 General requirements
6.2.2 Approach channel <\/td>\n<\/tr>\n
16<\/td>\n6.3 Weir structure
6.4 Downstream conditions
7 Maintenance <\/td>\n<\/tr>\n
17<\/td>\n8 Measurement of head(s)
8.1 General
8.2 Stilling (gauge) wells <\/td>\n<\/tr>\n
19<\/td>\n8.3 Zero setting <\/td>\n<\/tr>\n
21<\/td>\n8.4 Location of head measurement sections <\/td>\n<\/tr>\n
22<\/td>\n9 Discharge relationships
9.1 Equations of discharge <\/td>\n<\/tr>\n
23<\/td>\n9.2 Effective heads <\/td>\n<\/tr>\n
24<\/td>\n9.3 Shape factors
9.4 Coefficient of velocity <\/td>\n<\/tr>\n
26<\/td>\n9.5 Conditions for modular\/drowned flow <\/td>\n<\/tr>\n
29<\/td>\n9.6 Drowned flow reduction factor <\/td>\n<\/tr>\n
36<\/td>\n9.7 Limits of application <\/td>\n<\/tr>\n
37<\/td>\n10 Computation of discharge
10.1 General
10.2 Successive approximation method
10.2.1 Computation using individual head measurements <\/td>\n<\/tr>\n
38<\/td>\n10.2.2 Computation of modular stage-discharge function <\/td>\n<\/tr>\n
39<\/td>\n10.3 Coefficient of velocity method
10.3.1 Modular flow conditions
10.3.2 Drowned flow conditions <\/td>\n<\/tr>\n
40<\/td>\n10.4 Accuracy
11 Uncertainties in flow determination
11.1 General <\/td>\n<\/tr>\n
41<\/td>\n11.2 Combining uncertainties <\/td>\n<\/tr>\n
42<\/td>\n11.3 Uncertainty in the discharge coefficient u*(CDe)68 for the flat-V weir
11.4 Uncertainty in the drowned flow reduction factor u*(Cdr) <\/td>\n<\/tr>\n
43<\/td>\n11.5 Uncertainty in the effective head
11.6 Uncertainty budget <\/td>\n<\/tr>\n
44<\/td>\n11.7 Variation of uncertainty with flow and uncertainty in mean daily flow and the daily flow volume
11.7.1 Uncertainty curve <\/td>\n<\/tr>\n
45<\/td>\n11.7.2 Uncertainty in the daily mean flow
11.7.3 Uncertainty in the daily flow volume
12 Examples
12.1 Example 1\u00a0\u2014 Computation of modular flow at low discharge
12.1.1 Data <\/td>\n<\/tr>\n
46<\/td>\n12.1.2 Solution by successive approximation method (see 10.2) <\/td>\n<\/tr>\n
47<\/td>\n12.1.3 Solution by coefficient of velocity method (see 10.3)
12.2 Example 1\u00a0\u2014 Uncertainty in computed discharge
12.2.1 Uncertainty in the discharge coefficient
12.2.2 Uncertainty in drowned flow reduction factor
12.2.3 Uncertainty in the horizontal; component of the weir crest gradient
12.2.4 Uncertainty in the effective total head <\/td>\n<\/tr>\n
48<\/td>\n12.2.5 Overall uncertainty <\/td>\n<\/tr>\n
49<\/td>\n12.3 Example 2 \u2014 Computation of drowned flow at high discharge
12.3.1 Data
12.3.2 Solution using successive approximation method (see 10.2) <\/td>\n<\/tr>\n
50<\/td>\n12.3.3 Solution using the coefficient of velocity method (see 10.3) <\/td>\n<\/tr>\n
51<\/td>\n12.4 Example 2 \u2014 Uncertainty in computed discharge
12.4.1 Uncertainty in the discharge coefficient
12.4.2 Uncertainty in the horizontal; component of the weir crest gradient
12.4.3 Uncertainty in the effective total head <\/td>\n<\/tr>\n
52<\/td>\n12.4.4 Uncertainty in the separation pocket (crest tapping) head
12.4.5 Uncertainty in drowned flow reduction factor
12.4.6 Overall uncertainty for non-modular flow example <\/td>\n<\/tr>\n<\/table>\n","protected":false},"excerpt":{"rendered":"

Hydrometric determinations. Flow measurement in open channels using structures. Flat-V weirs<\/b><\/p>\n\n\n\n\n
Published By<\/td>\nPublication Date<\/td>\nNumber of Pages<\/td>\n<\/tr>\n
BSI<\/b><\/a><\/td>\n2012<\/td>\n70<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n","protected":false},"featured_media":293514,"template":"","meta":{"rank_math_lock_modified_date":false,"ep_exclude_from_search":false},"product_cat":[265,2641],"product_tag":[],"class_list":{"0":"post-293509","1":"product","2":"type-product","3":"status-publish","4":"has-post-thumbnail","6":"product_cat-17-120-20","7":"product_cat-bsi","9":"first","10":"instock","11":"sold-individually","12":"shipping-taxable","13":"purchasable","14":"product-type-simple"},"_links":{"self":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product\/293509","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/types\/product"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/media\/293514"}],"wp:attachment":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/media?parent=293509"}],"wp:term":[{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product_cat?post=293509"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product_tag?post=293509"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}