热的s affect us everyday, even without us knowing. Heat transfer is just a form of energy transfer. We're busy people and move energy around all the time. When you start thinking thermally, you begin to recognize heat flow in the things you do.
Something we do all the time is eat. And to eat we need to cook. Cooking is just a fun and artful method of heat transfer into edible products to make them more digestible and palatable. We're going to train our thermal vision onto a pot of boiling water. Boiling water is one of the essentials in cooking, though not all of us have a good handle on it.
让我们在这个日常热任务中找到三种传热（传导，对流和辐射）！
Here is our empty aluminum pot that we're going to fill with water. It's sitting on a glass top electric stove in the kitchen. Nothing to special when you think about it. It's only when we point our thermal camera that things get interesting. Thermal imaging camera's output a thermal contour image with different colors representing different temperatures. In this scale, we have dark blues as the coolest temperatures, to greens, yellows, orange, reds and up to white as the hottest temperatures.
Notice we have a few hot spots before we even get started. Since thermal camera's typically adjust their color range to whichever temperatures it sees, there isn't much temperature difference between these objects. Unfortunately, the images from our thermal camera don't save with the whole scale, but we've put some temperature probes on later images to show some actual temperatures.
So what's going on with these hot spots when we haven't even turned on the stove?
我们看到的最热门现货是炉子上的LED显示屏。随着炉子在展示时间，它可以发光和热量，这就是我们用相机看到的。在右上方，我们看到另一个更热的区域。这是一个电源插座。通过电线贯穿电线的电阻产生一点热量，因为干墙不隐藏它，热摄像机看到它。
所以我们来到锅上的两个明亮的斑点，尚未对此没有热量。明亮的黄点实际上是光线和热量来自厨房窗户的反射。和黄绿点？那是我的热反射。
由于热能可以辐射，因此它就像光一样。如果有闪亮的表面，就像我闪亮的锅一样，它将反映heat radiation。Full disclaimer, I already turned on the stove in this next picture. You can actually see in this image where on the left I'm just standing in front of the pot and on the right I'm hiding behind a cloth covered ironing board. You can see that green smudge in the middle is missing on the right hand pot image.
让我们打开热量！是时候添加一些水并打开炉子。我用水填满了大约半满的锅（是的，我们在这里宽容）。再次在此图像中，我们看到炉子的LED和图像顶部的电源插座。请注意，它们在此图像中的更大程度如何比上一个图像更高。炉子温度与这些东西之间的关系显着改变，并且更新了热图像的颜色以显示。我们还可以根据中绿色的逐渐变化来讲述，蓝绿色和较暗的蓝色，导致沿着锅的侧面带来升温。
We see the heat generated by the electric stove and how some of it's conducting up and away from the bottom of the pot. We can also see some of the thermal radiation being reflected out from the inside of the pot in the green area. As the stove top gets hotter, dark splotches start showing up on the hottest areas. I learned that this is an artifact of the thermal camera since the temperature in those areas are too hot for the camera to measure. For our camera that limit is 302.4°F or 150°C.
我们已经看到了辐射和传导，所以让我们找到一些convection。如果我们密切关注锅，首先，尽管它被观看了，并且第二，我们可以在开始沸腾之前看到一些蒸汽形成。观看水中的罐子在水上的罐中令人着迷，而GIF并不完全正义。作为侧面笔记，锅中的那些蓝色点是把手铆接到锅中的地方。那些比其他锅更凉爽，因为这些手柄基本上像散热器一样，从源极拉出热量。
一旦锅开始沸腾，更热的蒸汽停止在锅内滚动，开始上升和从锅中升起。通常有一个热空气升起的中央羽流，但行为是不可预测的。Natural convection严重依赖周围条件。环境空气中的小变化可能对蒸汽的中央羽流如何具有急剧效果。再次，令人着迷。
这是整个加热过程的时间流逝，具有几种温度探头，以提供一点尺度。
So there's the first of hopefully a long series! Everyday Thermals: Boiling Pot of Water. Didn't think something so mundane would look this exciting, right?
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