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<?xml-stylesheet type="text/xsl" href="https://communities.bentley.com/cfs-file/__key/system/syndication/rss.xsl" media="screen"?><rss version="2.0" xmlns:dc="http://purl.org/dc/elements/1.1/"><channel><title>levon batoyan's Activities</title><link>https://communities.bentley.com/members/bd79de90_2d00_ee1b_2d00_45a8_2d00_9318_2d00_99345aeb0a75</link><description>levon batoyan's recent activity</description><dc:language>en-US</dc:language><generator>Telligent Community 12</generator><item><title>Flow - pressure relation, emitter coefficient</title><link>https://communities.bentley.com/products/hydraulics___hydrology/f/haestad-hydraulics-and-hydrology-forum/219409/flow---pressure-relation-emitter-coefficient</link><pubDate>Mon, 13 Sep 2021 11:43:42 GMT</pubDate><guid isPermaLink="false">6dad98f5-dbc9-4c4d-a9ba-e9da8dc6aa8e:cc14cb84-2fa7-4e1c-ba1c-721d57cfd7eb</guid><dc:creator>levon batoyan</dc:creator><description>&lt;p&gt;&lt;span&gt;Hello,&lt;br /&gt;&lt;br /&gt;&lt;/span&gt;I have&amp;nbsp;a question related to the emitter coefficient of junction.&lt;br /&gt;&lt;br /&gt;My task is to determine how much will change&amp;nbsp;the flow at the downstream reservoir(which in the program I consider as a junction) if we&amp;nbsp;change pressure breaker elevation for +10m. (we know the material, diameter, length)&amp;nbsp;&lt;br /&gt;&lt;br /&gt;I tried to use&amp;nbsp;&lt;span&gt;The outflow from an orifice&lt;/span&gt;&lt;br /&gt;Q=CA sqrt(2gh)&amp;nbsp; &amp;nbsp; &amp;nbsp; &amp;nbsp;( C=0.62 from libraries)&lt;/p&gt;
&lt;p&gt;but watergems&amp;nbsp; uses&amp;nbsp;&lt;span&gt;emitter coefficient at the junction&amp;nbsp; &lt;br /&gt;Q = k&amp;nbsp;sqrt (P).&amp;nbsp;&amp;nbsp;&lt;br /&gt;&lt;br /&gt;is k&amp;nbsp;some kind of conversion factor between head and pressure?&lt;br /&gt;&lt;br /&gt;Can we write that&amp;nbsp;&lt;/span&gt;&lt;/p&gt;
&lt;p&gt;&lt;span&gt;k&lt;/span&gt;&lt;span&gt;&amp;nbsp;sqrt (P) =&amp;nbsp;CA sqrt(2gh)&amp;nbsp;&amp;nbsp;&lt;/span&gt;&lt;/p&gt;
&lt;p&gt;&lt;span&gt;&lt;br /&gt;&lt;br /&gt;please help me to accomplish this equation or give advice on how to solve this kind of task.&lt;br /&gt;&lt;br /&gt;&lt;br /&gt;&lt;br /&gt;&amp;nbsp;&amp;nbsp;&lt;/span&gt;&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>Ask A Question I</title><link>https://communities.bentley.com/achievements/460ac7df-7ccc-4c42-a204-9e05eef3be09</link><pubDate>Tue, 10 Aug 2021 00:00:45 GMT</pubDate><guid isPermaLink="false">6dad98f5-dbc9-4c4d-a9ba-e9da8dc6aa8e:6a416ded-6981-4f10-9551-0f7fd660c8f9</guid><dc:creator /><description>Ask a question in a forum.</description></item><item><title>Partially Closed Valves in water supply system</title><link>https://communities.bentley.com/products/hydraulics___hydrology/f/haestad-hydraulics-and-hydrology-forum/217898/partially-closed-valves-in-water-supply-system</link><pubDate>Tue, 10 Aug 2021 05:50:19 GMT</pubDate><guid isPermaLink="false">6dad98f5-dbc9-4c4d-a9ba-e9da8dc6aa8e:8e02fe1d-4426-4c41-8c85-de4a4d6e10b8</guid><dc:creator>levon batoyan</dc:creator><description>&lt;p&gt;&lt;span&gt;Hello,&lt;/span&gt;&lt;/p&gt;
&lt;p&gt;&lt;span&gt;I&amp;#39;m modeling a high pressured water supply system full of partially closed valves (which people use as some kind of &amp;quot;prv&amp;#39;s&amp;quot; to reduce pressure because&amp;nbsp;they don&amp;#39;t have enough money to buy it).&lt;br /&gt;The information they gave me is D(mm) of a valve, type of the valve, pressure before and after the valve (M h2o), and how much flow goes through it after partially closing it (l/s).&amp;nbsp;&lt;br /&gt;&lt;br /&gt;for instance,&amp;nbsp; &amp;nbsp;pressure before and after the valve is 75m, valve D=150mm, after partially closing it becomes after the valve 20m and 5 l/s goes through it.&lt;br /&gt;&lt;br /&gt;&lt;br /&gt;I used hc=kv&lt;sup&gt;2&lt;/sup&gt;/2g&amp;nbsp; equation to find headloss coefficient setting&lt;br /&gt;&lt;br /&gt;75 - 20 = k(4Q/3.14D&lt;sup&gt;2&lt;/sup&gt;)&lt;sup&gt;2&lt;/sup&gt;/2g&lt;br /&gt;&lt;br /&gt;k=13750&lt;/span&gt;&lt;/p&gt;
&lt;p&gt;&lt;span&gt;&lt;br /&gt;but how precise is it?&amp;nbsp;how precise&amp;nbsp;would&amp;nbsp;it be in eps modeling?&lt;/span&gt;&lt;/p&gt;
&lt;p&gt;&lt;span&gt;How to model this kind of system in watergems?&amp;nbsp;&lt;br /&gt;&lt;br /&gt;&lt;/span&gt;&lt;/p&gt;
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