[Applause] [掌声]
hey there guys Paul here from the 嘿家伙保罗在这里从
engineering mindset calm in this video 工程师的心态冷静在这个视频
we're gonna be looking at pump 我们要看看泵
calculations and specifically we're 计算，特别是我们
gonna be looking at how to calculate the 会看着如何计算
flow rate the pump rpm the revolutions 流量泵的转速，转速
per minute the head pressure the pump 每分钟的泵头压力
power and also the impeller diameter now 功率和现在的叶轮直径
if you already have a pump installed in 如果您已经安装了泵
one of your buildings then you should 你的建筑物之一，你应该
have a checklist or a sheet that comes 有一个清单或表来
like this which is the data sheet for 像这是数据表
that pump now all too often parts that 现在泵常常是件
desert parts of this design data are 这个设计数据的沙漠部分是
missing that's really frustrating but if 错过这真的令人沮丧，但如果
you have got some data missing then 那么你缺少一些数据
we're gonna look at some formulas of how 我们将看看如何的一些公式
to calculate and fill in these gaps and 来计算和填补这些差距和
also we'll look to see what would happen 我们也会看看会发生什么
if you were to change some of these 如果你要改变其中的一些
parameters now of course if you haven't 参数现在当然，如果你还没有
got the pump installed yet you're in a 得到了尚未安装泵你在一个
design phase then you can also use these 设计阶段，那么你也可以使用这些
formulas to determine what the 公式来确定什么
performance will be so these formulas 性能将如此这些公式
will give us the values of the pump 会给我们泵的价值
performance curve now do remember that 性能曲线现在确实记得这一点
these calculations will only give us 这些计算只会给我们
fear ethical values the actual 恐惧伦理价值的实际
performance may vary from these and you 性能可能会因您而异
know certainly the older pump gets the 肯定知道老泵得到了
larger discrepancy becomes between the 两者之间的差距越来越大
theoretical in the actual and so you 在实际和你的理论
might need to add on a correction factor 可能需要添加修正因子
to adjust these but for everyday 调整这些，但每天
purposes and for your studies this is 目的和你的学习是这样的
fine so if we jump into the calculations 好吧，如果我们跳进计算
you can see first of all that I've split 首先你会看到我已经分裂了
the screen into two parts being the 屏幕分为两部分
metric and imperial so we couldn't look 公制和帝国，所以我们看不到
through the calculations for both of 通过两者的计算
these I've also tried to color code all 这些我也尝试着色所有代码
the the figures we'll have so you can 我们将拥有的数字可以
follow those all the way through because 遵循这些所有的方式，因为
sometimes it does get a bit confusing 有时它变得有点 混乱
obviously chasing these numbers through 显然通过追逐这些数字
so that should make it a little bit 所以应该使它有点
easier so if this calculation this is 如果这是这样的计算，那更容易
we're gonna find out what the new flavor 我们要找出新的味道
eight flow rate would be if we were to 如果我们愿意的话，八个流量将是
increase or decrease the pump 增加或减少泵
revolutions per minute and to do that 革命每分钟，并做到这一点
we're gonna use this formula here so 我们在这里会经常用到这个公式，以便
we've got the flow rate the new flow 我们已经获得了新流量的流量
rate is equal to the revolutions per 费率等于每次革命
minute the new one multiplied by the 分钟新建一个乘以
division of the old flow rate divided by 旧流量的划分除以
the RPM RPM
the old system so if we drop the figures 旧系统， 所以如果我们放弃数字
in for there we can see that originally 在那里，我们可以看到，原本
that the pump would have 57 liters per 该泵将有57升每个
second and we've got the the the 第二，我们已经掌握了
adjusted rpm and the original rpm these 调整转速和原始转速这些
are the same have done the in the 是一样的在做
Imperial in gallons per minute for the 帝国以每分钟加仑为单位
metric I will just point out that I've 指标我会指出我已经
used liters per second here it should 它应该在这里每秒使用升
really be meters cube per second but 真的是米立方每秒， 但
almost always the pumps are listed in 几乎所有的泵都被列入
liters per second and it doesn't 升每秒，而不是
particularly matter about this the 特别是关于这件事的事情
unit's you use the unit's you put in and 单位的你使用单位的你放入和
the units that you're going to get out 你要去单位脱身
so you can change it to meters cube per 所以您可以将其更改为每米多维数据集
second or kilograms per second and it 秒或千克每秒和它
will come out the same just you know 只要你知道就会出来
remain consistent throughout anyway if 整个无论如何，如果保持一致
you do the calculations for these then 你做这些计算然后
you'll see that this comes out to fifty 你会看到这个数字达到五十
two point six liters per second or 833 两点六升每秒或833
gallons per minute so the next one we're 加仑每分钟，所以下一个我们
going to look at is the new flow rate 要看的是新的流量
and that would occur if you were to 如果你愿意的话会发生
change the impeller diameter now we will 现在我们将改变叶轮直径
point out that this is this isn't an 指出，这是，这是不是一个
older way to do this if it's already 如果已经存在，则采用较旧的方法
existing social each room down the 现有的社交每个房间下来了
impeller to change its diameter it's not 叶轮改变其直径不是
the preferred way anymore and that's 的首选方式了，这就是
because if you want you trim it down you 因为如果你想你修剪下来你
can't obviously add that material back 不能明显加回那些材料
on so you need to replace the entire 因此你需要更换整个
impeller a much better way yesterday 推动昨天更好的方式
actually use a variable speed driver a 实际上使用一个变速驱动器a
variable frequency drive to change the 变频器改变了
speed of the pump to to meet the your 泵的速度来满足你的需求
design criteria but if you are looking 设计标准，但如果你正在寻找
to change the impeller or to even trim 改变叶轮或甚至修剪
the impeller down then you can use these 叶轮下来然后你可以使用这些
calculations here so for this one the 这里计算这个这个
new flow rate would be equal to the new 新的流量将等于新的流量
diameter of the impeller multiplied by 叶轮乘以的直径
the old flow rate divided by the 旧流率分
diameter of the old impeller and if we 旧叶轮的直径， 如果我们
drop those figures in and we're going to 放下这些数字，我们会去的
come down to that you can see comes to 归结为你可以看到
fifty two point six liters per second or 五十二点六升每秒或
eight free--free gallons per minute 每分钟八个免费加仑
now the next one we'll look at is the 现在我们要看的下一个是
pump rpm the revolutions per minute so 泵转速每分钟的转数
if we were to increase or decrease the 如果我们要增加或减少
flow rate what RPM would we need to 流量我们需要什么RPM
achieve that and we can use this formula 实现这一点，我们可以使用这个公式
here to find that out so the new rpm 在这里可以找到新的rpm
revolutions per minute he calls the old 他称之为旧的每分钟革命
rpm multiplied by the new flow rate 转速乘以新的流量
divided by the 除以
original flow rate and if we add those 原始流量，如果我们加上这些
figures in there you can see here that 在那里你可以看到这个数字
these two units of measurement cancel 这两个测量单位取消
out and so that leaves you with a ratio 出去，所以这会让你有一个比例
or percent and so you multiply these out 或百分比，所以你乘以这些
together and that will bring you down to 一起，将带给你下来
1300 rpm so that is the speed that the 1300 转，这样的速度是
the impeller nisa rotator in order to 叶轮尼萨旋转器为了
achieve this new flow rate so the next 实现这个新的流量，所以下一个
one we'll look at is how to calculate 我们要看的是如何计算
the head pressure and this would occur 头部压力会发生
if you were to increase or decrease the 如果你要增加或减少
revolutions per minute of the impeller 叶轮的每分钟转数
and to do that we can use this formula 并做到这一点，我们可以使用这个公式
here so the head pressure the new head 在这里头压力新头
pressure is equal to the RPM of the new 压力等于新的RPM
the new revolutions per minute 每分钟新的革命
squared multiplied by the old prep old 平方乘以旧的旧的
head pressure divided by the old 头部压力除以旧
revolutions per minute squared as well 每分钟的转数也是平方
now pay particular attention to this one 现在要特别注意这一点
and make sure you square both of the 并确保你平方米的两个
rpms all too often people forget to do RPMS但人们往往忘记做
this and the numbers they just come out 这和他们刚刚出来的数字
peripherally L is very embarrassing so 外围L很令人尴尬
obviously make sure you double-check 显然要确保你仔细检查
that 那
you'll also notice here that I've 你也会在这里注意到我已经
written these numbers out and for really 把这些数字写出来，并真的
you should put these in standard form 你应该把它们放在标准的形式中
but I've just put these out so you can 但我只是把这些放在一边，所以你可以
you can see them very clearly what the 你可以很清楚地看到他们是什么
numbers are and how we get to this final 数字是以及我们如何进入决赛
figure here but if you're doing this for 在这里图，但如果你这样做
work or an exam etcetera then put them 工作或再考试诸如此类把它们
into standard form but anyway if we we 进入标准形式，但无论如何，如果我们
drop the numbers in and work our way 放下数字并按我们的方式工作
through these then we'll come down for 通过这些，我们会下来的
use very large numbers all the way until 直到 使用非常大的数字
we get to the new head pressure which 我们遇到了新的压力
would be 364 kPa or 122 feet of water 将是364千帕或122英尺的水
the next one we'll look at is also head 下一个我们会看到的也是头
pressure and that will be how to 压力，这将是怎样
calculate this should you increase or 计算这应该你增加还是
decrease the flow rate and we can use 减少流量，我们可以使用
this equation here this formula here to 这个公式在这里这个公式在这里
calculate that so the new head pressure 计算出这样的新头压力
is equal to the old head pressure 是等于旧头压力
multiplied by the division of the new 乘以新的划分
flow rate divided by the old flow rate 流量除以旧流量
and make sure you square the the number 并确保你将数字平方
you get from this division as well so if 你也可以从这个部门获得，如果
we drop some of some of the numbers in 我们放弃了一些一些数字中
there and we can see how this plays out 那里，我们可以看到这是如何发挥
also remember like I said to do the 还记得像我说的那样
division and 师和
then square this number here so you get 然后在这里把这个数字平方，这样就可以得到
this up and then you get to your final 这一点，然后你进入你的决赛
number which is just your ratio or 数字，这只是你的比例或
percent and drop these in multiply them 百分比， 并放弃这些乘以它们
out and you'll see you come to 364 kPa 出去， 你会看到你来到364千帕
or 122 feet of water so the next one 或122英尺深的水中，以便下一个
we'll look at is the pump power and that 我们来看看是泵浦功率和
will be how to calculate what the new 将如何计算出新的东西
pump power would be should you increase 如果你增加泵的功率
or decrease the revolution per minute of 或减少每分钟的转数
the pump or from the you know from the 泵或从你知道的
motor and to do that we can use this 马达， 并做到这一点，我们可以使用它
equation here so the power the new power 等式在这里所以权力的新力量
is equal to the RPM the new revolutions 等于RPM新转
per minute cubed multiplied by the 每分钟立方乘以
division of the old power divided by the 旧力量的划分除以
RPM the revolutions per minute of the 每 RPM的分钟转数
old cubed that as well so if we drop the 旧的立方体，以及如果我们放弃了
figures in 4 there as well then you'll 数字在4那里，那么你会的
see this will all come out like this 看到这一切都会像这样出来
again I haven't written these out in 我还没有写出这些
standard form you should do it 标准形式你应该这样做
especially if you're going in for the 特别是如果你打算去的话
exam you're taking this data in with you 你正在将这些数据与你一起考试
make sure to put it in standard form but 一定要把它放在标准的形式，但
I've just written these out in long form 我刚刚写出了这些
just to make it very clear what the 只是使它非常清楚什么
numbers are and how we get to these 数字是，我们如何得到这些
final figures so you can see if you to 最后的数字，所以你可以看到，如果你
calculate all these remember to cube 计算所有这些记得立方体
these numbers as well obviously that's 这些数字显然也是如此
why they are so long make sure you do 为什么他们这么长时间确保你做到了
these is the first step otherwise you 否则这是你的第一步
might lose it and then you'll mess up 可能会失去它，然后你会搞砸
all your calculations so don't fall into 所有的计算都不会落入
that trap so we gather all this and 那个陷阱，所以我们收集所有这些和
you'll see it comes down to 35 point 4 你会发现它降到了35分4
kilowatts down from 45 kilowatts and on 千瓦从45千瓦下降
the Imperial side it will come down from 帝国方它将从回落
60 point three five horsepower down to 60点三五匹马力降下来
forty seven point five horsepower and 四十七点五马力和
the last one we're going to look at is 最后一个我们要看看是
the impeller diameter so if you were to 叶轮的直径，所以如果你想
adjust the flow rate and you wanted to 调整流量，你想
achieve this new flow rate what diameter 达到这个新的流量直径
impeller would you need and this is 你需要叶轮，这是
usually used in the case where the 通常在使用的情况下使用
impeller is being trimmed down to meet a 正在修剪叶轮以满足a
new flow rate and so that's what I've 新的流量，所以这就是我的
done in the calculations here as well 这里的计算也完成了
you can see that originally it was 57 你可以看到它最初是57
litres per second on 903 point five 903点每秒升到5点
gallons per minute and the new flow rate 加仑每分钟和新的流量
which I want to achieve when the metric 我想实现在 公制
side is fifty two point six liters per 一边是五十二点六升每个
second 第二
eight hundred and thirty three point 八百三十三点
seven gallons per minute so if we used 如果我们使用，每分钟七加仑
to drop those numbers in and start doing 放下这些数字并开始做
the calculations you'll see that these 你会看到这些计算
two the units of measurement cancel out 测量的两个单元 抵消
and that becomes a ratio or percent and 这成为一个比例或百分比和
if we multiply that out put them both 如果我们把它们放在一起就把它们都放在一起
together then we will come down and get 一起然后我们会下来并得到
the final answer of one hundred eighty 一百八十的最终答案
four point five six millimeters diameter 四点五毫米直径
or seven point two six inches so that is 或七点二六英寸，这是
it for this video thank you very much 它为这个视频非常感谢你
for watching I hope this has helped if 因为看我希望这有助于如果
you have any questions please leave them 您有任何疑问，请让他们
in a comment section below don't forget 在下面的评论部分不要忘记
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