关于西方家庭中使用的热水存储罐方面

 

  

Hot water storage tank（热水存储罐）

 

 

资料来源，维基百科：

 

 

https://en.wikipedia.org/wiki/Hot_water_storage_tank

 

 

 

 

A hot water storage tank (also called a hot water tank, thermal storage tank, hot water thermal storage unit, heat storage tank and hot water cylinder) is a water tank used for storing hot water for space heating or domestic use.

（热水存储罐，是指用于储存供暖空间使用的热水或者家庭使用的热水的储水箱，也称为热水存储箱，储热水箱，热水储热水箱，储热水箱，热水储水水箱）。）

 

 

Water is a convenient heat storage medium because it has a high specific heat capacity.

（水是一种方便的蓄热介质，因为它具有较高的比热容。）

（“比热容” (Specific Heat Capacity)，用符号c表示，又称“比热容量”，简称“比热” (specific heat)，是单位质量物质的热容量，即，单位质量物体改变单位温度时吸收或放出的热量。）

 

 

This means, compared to other substances, it can store more heat per unit of weight. Water is non-toxic and low cost.

（这意味着，与其他物质相比，它可以储存更多的单位重量的热量。 水无毒，成本低。）

 

 

An efficiently insulated tank can retain stored heat for days, reducing fuel costs.

（一个高效隔热的水箱可以储存好几天的热量，从而降低燃料成本。）

 

 

Hot water tanks may have a built-in gas or oil burner system, electric immersion heaters.

（热水罐可能有内置的燃气或燃油燃烧器系统，电浸没式加热器。）

 

 

Some types use an external heat exchanger such as a central heating system, or heated water from another energy source.

（有些类型使用外部的热交换器，如集中供暖系统，或来自另一能源的热水。）

 

 

The most typical, in the domestic context, is a fossil-fuel burner, electric immersion elements, or a district heating scheme.

（家用方面，最典型的是化石燃料燃烧器、电浸没元件或区域供热方案。）

 

 

Water heaters for washing, bathing, or laundry have thermostat controls to regulate the temperature, in the range of 40 to 60 °C (104 to 140 °F), and are connected to the domestic cold water supply.

（用于洗涤、洗浴或洗衣的热水器有恒温器调节器调节温度，在40至60°C（104至140华氏度）范围内，并连接到家用冷水供应系统。）

 

 

Where the local water supply has a high content of dissolved minerals such as limestone, heating the water causes the minerals to precipitate in the tank (scaling).

（在当地的供水系统中，石灰石等溶解性矿物含量很高，加热水会使矿物质在罐中沉淀（结垢）。）

 

 

A tank may develop leaks due to corrosion after only a few years, a problem exacerbated by dissolved oxygen in the water which accelerates corrosion of both tank and fittings.

（在短短几年的时间内, 存水箱可能会产生泄漏, 这是由于水中溶解氧加剧了水箱和配件的腐蚀。）

 

 

 

  

Two red parallelled hot water storage tanks connected to a wood-fueled furnace.

（两个红色并联热水储水箱连接到木材燃料炉。）

 

 

A hot water storage tank where one of the heat sources is solar heating A, that is sent into the hot water storage tank via a smaller pump B (circle with triangle) and the heat exchanger spiral in the hot water storage tank.

（热水储存罐，其中一个，热源是太阳能加热（图中：A），通过一个较小的泵（图中：B，带有三角形的圆圈）和螺旋状（铜管）热交换器进入热水储罐中。）

 

 

The other spiral C can be used for a e.g. oil-fired boiler or a wood burner.

（另一个螺旋状（铜管）（图中：C）可用于燃油锅炉或木材燃烧器。）

 

 

（以上2段英文说明：热交换热水存储罐中，释放热量，加工热水的热源有2种，一个是太阳能热，一个是燃油锅炉热，或者是燃烧木质燃料的锅炉热，当然，螺旋状铜管散热器的散热效果较好。）

 

At D the hot water gets out and domestic cold water is sent back at the bottom at E.

（在图中D处，热水流出，生冷水在图中E处被送回。）

 

 

 

A hot water storage tank where one of the heat sources is solar heating.

（热水储存箱，其中一个热源是太阳能加热。）

 

 

Almost the same example as above, but in a domestic habitat.

（几乎和上面的例子一样，但是在家庭内部。）

 

 

Insulation（热水存储罐的保温隔热方面）

 

 

Typically hot water storage tanks are wrapped in heat insulation to reduce energy consumption, speed up the heating process, and maintain the desired operating temperature.

（热水储水箱通常用隔热层包装，以减少能耗，加快加热过程，并保持预期的工作温度。）

 

 

Thicker thermal insulation reduces standby heat loss. （较厚的隔热层减少待机热损失。）

 

 

Water heaters are available with various insulation ratings but it is possible to add layers of extra insulation on the outside of a water heater to reduce heat loss.

（热水器有不同的绝缘等级，但可以在热水器的外部加上一层额外的隔热层以减少热量损失。）

 

 

In extreme conditions, the heater itself might be wholly enclosed in a specially constructed insulated space.

（在极端条件下，加热器本身可能被完全封闭在一个专门构建的绝缘空间内。）

 

 

The most commonly available type of water heater insulation is fiberglass, fixed in place with tape or straps or the outer jacket of the water heater.

（最常用的热水器隔热材料是玻璃纤维，热水器的外壳，用胶带或带子固定。）

 

 

Insulation must not block air flow or combustion gas outflow, where a burner is used.

（使用燃烧器，绝缘外壳，不能阻止空气流动或燃烧气体流出。）

 

 

In extremely humid locations, adding insulation to an already well-insulated tank may cause condensation leading to rust, mold, or other operational problems so some air flow must be maintained, usually by convection caused by waste heat, but in particularly humid conditions such ventilation may be fan-assisted.

（在极端潮湿的地方，在已经很好保温的水箱中添加绝缘材料可能会导致冷凝，导致生锈、霉菌或其他操作问题，因此必须保持一些气流，通常是由废热引起的对流，但在特别潮湿的情况下，这种通风可能是由风扇辅助的。）

 

 

Most modern water heaters have applied polyurethane foam (PUF) insulation.

（大多数现代热水器使用聚氨酯泡沫（PUF）绝缘。）

 

 

Where access to the inner tank is a priority (in cases of particularly aggressive minerals or oxygen levels in the local water supply) the PUF can be applied in encapsulated form, allowing the removal of insulation layer for regular integrity checks and if required, repairs to the water tank.

（在进入内罐是当务之急（在当地水供应特别积极的矿物或含氧量例）PUF可用于封装形式，允许定期完整性检查绝缘层的去除，如果需要的话，修理水箱。）

 

 

Solar hot water storage tank（太阳能热水存储罐）

 

 

In a solar water heating system, a solar hot water storage tank stores heat from solar thermal collectors. 

（在太阳能热水系统中，太阳能热水储存罐储存来自太阳能集热器的热量。）

The tank has a built-in heat-exchanger to heat domestic cold water. 

（水箱有一个内置的热交换器加热家用冷水。）

In relatively mild climates, such as the Mediterranean, the (heavily insulated but metal-wrapped) storage tanks are often roof-mounted. 

（在相对温和的气候，如地中海，（绝缘但金属包裹的）储罐通常是屋顶安装的。）

All such tanks share the same problems as artificially-heated tanks including limestone deposit and corrosion, and suffer similar reductions in overall efficiency unless scrupulously maintained.

 （所有这些储罐与人工加热的储罐，包括石灰石沉积和腐蚀，都存在同样的问题，除非严格维护，否则总的效率会降低。）

 

Water tank leakage（水箱渗漏）

 

 

Water heater tanks may be made of vitreous enamel-lined carbon steel, stainless steel, or copper.

 

 

While copper and stainless steel domestic hot water tanks are more commonplace in Europe, carbon steel tanks are more common in the United States, where typically the periodic check is neglected, the tank develops a leak whereupon the entire appliance is replaced. Even when neglected, carbon steel tanks tend to last for a few years more than their manufacturer's warranty, which is typically 3 to 12 years in the US.

 

 

Vitreous-lined tanks are much lower in initial cost, and often include one or more sacrificial anode rods designed to protect the tank from perforation caused by corrosion[5] made necessary since chlorinated water is very corrosive to carbon steel. As it is very nearly impossible to apply any protective coating perfectly (without microscopic cracks or pinhole defects in the protective layer) manufacturers may recommend a periodic check of any sacrificial anode, replacing it when necessary.

 

 

Some manufacturers offer an extended warranty kit that includes a replacement anode rod. Because conventional hot water storage tanks can be expected to leak every 5 to 15 years, high-quality installations will include, and most US building/plumbing codes now require, a shallow metal or plastic pan to collect the seepage when it occurs.

 

 

Hot water storage tank with closed water circuit（封闭水回路的热水存储罐）

 

 

This method stores heat in a tank by using external heat-exchangers (coils) that can be directly tapped or used to power other (external) heat-exchangers.

 

 

The chief benefit is that by avoiding drawing-off domestic hot water directly, the tank is not continually fed with cold water, which in 'hard' water areas reduces the deposit of limescale to whatever is dissolved in the original charge of water plus relatively trivial amounts added to replace losses due to seepage.

 

 

An added benefit is reduced oxygen levels in such a closed system, which allows for some relaxation in the requirements for materials used in the hot water storage tank and the closed water circuits, external heat exchangers, and associated pipework.

 

 

While an external heat exchanger system used for domestic hot water will have mineral deposits, descaling agents extend the life of such a system.

 

 

Stratified hot water storage tank with closed water circuit

（封闭水回路分层热水存储罐）

 

 

For an illustration - see reference（为了说明 - 请参阅参考）

 

 

Another method to store heat in a hot water storage tank has many names: 

Stratified hot water storage tank with closed water circuit, stratified thermal storage, thermocline tank and water stratified tank storage but in all cases the significant difference is that pains are taken to maintain the vertical stratification of the water column, in other words to keep the hot water at the top of the tank while the water at the bottom is at a distinctly lower temperature.

 

 

This is desirable in places with a wide climatic range where summer cooling is as important as heating in winter, and entails one or more of the following measures:

 

 

Different heating and cooling loops must send the heated or cooled water in with as low a velocity as possible. (This necessarily entails heating and cooling loops having velocity controlled pumps and tube ports with the maximum feasible diameter.)

 

 

For cooling applications, cool water is sent out from the bottom and warm (return) water is fed in at the top.

 

 

Heating applications get hot water out at the top and return cool water to the bottom.

 

 

"Stratification-enhancing" devices within the hot water storage tank (but if the water inlet velocity is as low as possible this might not be needed).

 

 

A more advanced heat control system is required.

 

 

When a stratified hot water storage tank has closed water circuits, the water temperatures can be up to 90 to 95 °C at the top and 20 to 40 °C at the bottom. 

Calm, undisturbed water is a relatively poor heat conductor when compared to glass, bricks and soil.

 

 

(Illustrated by a still lake, where the surface water can be comfortably warm for swimming but deeper layers be so cold as to represent a danger to swimmers, the same effect as gives rise to notices in London's city docks warning 'Danger Cold Deep Water).

 

 

Accordingly, an arbitrary volume of hot water can be stored, as long as the stratification is kept intact. In this case there must not be vertical metal plates or tubes as they would conduct heat through the water layers, defeating the purpose of stratification. 

When effectively employed this technique can maintain water as high as 95 °C (i.e. just below boiling) yielding a higher energy density, and this energy can be stored a long time provided the hot water remains undiluted.

 

 

Depending on the purpose of the installations, water exchanges tapping different levels allow water temperatures appropriate to the required use to be selected.

 

 

In many solar heating systems the energy parameters can be read as a function of time, from the 'dwell' time necessary to transform daylight into heat, at its peak the maximum hot water temperature near the top of the tank.

 

 

Dual element electric（双元件电动）

 

 

When flow starts from the uppermost outlet, cold water enters the tank at the bottom. 

（当水流从最上面的出口开始时，冷水进入底部的水箱。）

This drop in temperature causes the thermostat to switch on the electric heating element at the bottom of the tank. 

（温度下降导致恒温器打开水箱底部的电加热元件。）

When the water at the top of the tank is drawn off the hot water at the top is displaced by relatively cooler water, the top thermostat turns the top element on. 

（当水箱顶部的水被抽出时，顶部的热水被相对较冷的水所取代，顶部的恒温器将顶部的元件打开。）

When the flow stops, the elements stay on until their settings are met.

 （当流程停止时，元素保持不变，直到满足它们的设置。）

 

While it is common to have the top and bottom thermostats set differently in order to save energy, the fact that hot water rises means the thermostat controlling the upper element should feed the hottest supply, while the lower element the warmest.

 （虽然为了节约能源而将顶部和底部恒温器设置成不同的情况是常见的，但是热水上升的事实意味着控制上部元件的恒温器应当供给最热的供给，而下部元件是最热的。）

 

If the thermostats in such a system are reversed - warm feed from the top, hot from the center - it may not only affect the energy efficiency of the system, feeding scalding water to a domestic hot water outlet may be dangerous, or if directed to warm-feed washers damage them beyond repair.

 （如果这种系统的温控器是颠倒的，从顶部加热，从中心加热，它不仅可能影响系统的能量效率，将滚烫的水送到家用热水出口可能是危险的，或者如果指向暖送式洗衣机，损坏它们就无法修复。）

 

Safety issues（安全问题）

 

 

Hot water can cause painful, dangerous scalding injuries, especially in children and the elderly. 

（热水会引起痛苦、危险的烫伤，尤其是儿童和老人。）

Water at the outlet should not exceed 49 degrees Celsius. 

（出口处的水温不得超过49摄氏度。）

Some jurisdictions set a limit of 49 degrees on tank setpoint temperature. 

（一些司法管辖区对罐温度设定了49度的限制。）

On the other hand, water stored below 60 degrees Celsius can permit the growth of bacteria, such as those that cause Legionnaire's disease, which is a particular danger to those with compromised immune systems. 

（另一方面，储存在摄氏60度以下的水，可以允许细菌生长，例如，那些引起军团的疾病，这对那些免疫系统受损的人来说，是特别危险的。）

One technical solution would be use of mixing valves at outlets used for sinks, baths or showers, that would automatically mix cold water to maintain a maximum below 49 C. 

（一种技术解决方案是在水槽、浴缸或淋浴间使用混合阀，这样可以自动混合冷水，使其最大限度地保持在49 C以下。）

A proposal to add this to the building code of Canada was unsuccessful.

（建议将此添加到加拿大建筑规范中是不成功的。） 

 

 

热交换热水存储罐中产生的热水，供暖和生活热水使用，示意图。






屋顶太阳能集热系统 + 室内燃料锅炉系统，在热交换热水存储罐中，制造热水，供暖和生活热水使用，示意图。

屋顶太阳能集热系统 + 室内燃料锅炉系统，在热交换热水存储罐中，制造热水，示意图。

屋顶太阳能集热系统 + 室内火炉系统，在热交换热水存储罐中，制造热水，示意图。







屋顶太阳能集热系统 + 室内燃料锅炉系统，在热交换热水存储罐中，制造热水，示意图。









屋顶太阳能集热系统 + 室内燃料锅炉系统，在热交换热水存储罐中，制造热水，示意图。







屋顶太阳能集热系统 + 室内燃料锅炉系统，在热交换热水存储罐中，制造热水，示意图。

热交换热水存储罐剖解示意图——


























铜管材质的螺旋状热交换散热器几例——