应急柴油发电机房的设计（二） Design of Emergency Diesel Generator Room (II)

柴油发电机是一种小型发电设备，系指以柴油等为燃料，以柴油机为原动机带动发电机发电的动力机械。整套机组一般由柴油机、发电机、控制箱、燃油箱、起动和控制用蓄电瓶、保护装置、应急柜等部件组成。可用于各种家庭、办公室、大中小型企业日常发电以及应急发电。

  柴油发电机组是柴油发动机与发电机（通常是交流发电机）的组合以产生电能。 柴油压燃式发动机通常设计成在燃油上运行，但是有一些类型适用于其他液体燃料或天然气。发电机是将其他形式的能源转换成电能的机械设备。

  随着社会的发展，人民生活水平的提高，在现代民用建筑当中，用电设备的种类和数量越来越多，在这些用电设备当中，不仅有消防泵、喷淋泵等消防设备，还有需要可靠供电的生活泵、电梯等用电设备，为满足这些设备用电的可靠性，当市政电网无法提供两路独立电源时，在设计中采用柴油发电机组作为备用电源的方法被普遍采用。

  虽然柴油燃点较高，发生火灾危险性相对较小，但是在民用建筑中是将柴油发电机组设置在建筑物主体内，从理论上来说肯定还是有危险性的，再考虑到机组运行过程中通风、噪音、振动等问题，无疑需要我们全面考虑并采取充分的防范措施。

进、排风的设计

  柴油发电机房的通风问题是机房设计中要特别注意解决的问题，特别是机房位于地下室更要处理好，否则会直接影响发电机组的运行。机组的排风一般应设热风管道有组织的进行，不宜让柴油机散热器把热量散在机房内，热风管道与柴油机散热器连在一起其连接处用软接头，热风管道应平直，如果要转弯，转弯半径应尽量大而且内部要平滑，出风口尽量靠近且正对散热器，热风管直接伸出室外有困难时可设管导出。机房内要有足够的新风补充，进风一般为自然进风方式，进风口宜正对发电机端或发电机端两侧。进风口与出风口宜分别设在机房两端，以免形成气流短路，影响散热效果。

典型的进、排风口布置如方案如下： 

方案一：布置完全符合上面各条件的要求，是最优选择。但在实际设计中在建筑平面上无法找到两面临外墙的发电机房。仅一面临外墙。

方案二：布置是设计中可以选择的方案，此方案进、排风口的位置不应设在同一高度，一般小于800kW的发电机组进排风口的间距应在10米左右。

方案三：在建筑平面实在无法找到靠外墙的机房位置，机房设于建筑物中间，此方案进、排风应设管道，排风管道应作隔热处理，此方案不宜选用。

方案四：典型错误方案，无新风进入，而废气排进地下室，严重影响地下室的空气质量，不符合环保要求。

A diesel generator is a small power generation device that refers to a power machinery that uses diesel or other fuels and a diesel engine as the prime mover to drive the generator to generate electricity. The entire unit is generally composed of components such as a diesel engine, generator, control box, fuel tank, starting and control battery, protective device, emergency cabinet, etc. Can be used for daily power generation and emergency power generation in various households, offices, large, medium and small enterprises.

A diesel generator set is a combination of a diesel engine and a generator (usually an AC generator) to generate electrical energy. Diesel compression ignition engines are typically designed to run on fuel, but there are some types that are suitable for other liquid fuels or natural gas. A generator is a mechanical device that converts other forms of energy into electrical energy.

With the development of society and the improvement of people's living standards, there are more and more types and quantities of electrical equipment in modern civil buildings. Among these electrical equipment, there are not only fire-fighting equipment such as fire pumps and sprinkler pumps, but also electrical equipment such as domestic pumps and elevators that require reliable power supply. In order to meet the reliability of power supply for these equipment, when the municipal power grid cannot provide two independent power sources, the method of using diesel generator sets as backup power sources in the design is widely adopted.

Although diesel has a high ignition point and a relatively low risk of fire, it is theoretically still dangerous to install diesel generator sets inside the main structure of civil buildings. Considering issues such as ventilation, noise, and vibration during unit operation, it is undoubtedly necessary for us to comprehensively consider and take sufficient preventive measures.

Design of intake and exhaust air

The ventilation problem of diesel generator room is a special issue that needs to be addressed in the design of the room, especially when the room is located in the basement, otherwise it will directly affect the operation of the generator set. The exhaust of the unit should generally be carried out in an organized manner through a hot air duct. It is not advisable to allow the diesel engine radiator to dissipate heat inside the engine room. The hot air duct should be connected to the diesel engine radiator with a soft joint at the connection point. The hot air duct should be straight. If a turn is needed, the turning radius should be as large as possible and the interior should be smooth. The air outlet should be as close to and facing the radiator as possible. If it is difficult for the hot air duct to extend directly outside, a pipe can be installed to export it. There should be sufficient fresh air supply in the computer room, and the air intake is generally natural. The air inlet should face the generator end or both sides of the generator end. The air inlet and outlet should be located at both ends of the computer room to avoid the formation of airflow short circuits and affect the heat dissipation effect.

The typical layout of air inlet and outlet is as follows:

Option 1: Layout that fully meets the requirements of the above conditions is the optimal choice. But in actual design, it is impossible to find two generator rooms facing the exterior walls on the building plan. Only facing the exterior wall.

Option 2: Layout is an optional design option, and the positions of the air inlet and outlet should not be set at the same height. Generally, the spacing between the air inlet and outlet of a generator set with a power of less than 800kW should be around 10 meters.

Option 3: It is impossible to find the location of the computer room near the exterior wall in the building plan. The computer room is located in the middle of the building. This option requires the installation of ducts for air intake and exhaust, and the exhaust ducts should be insulated. This option is not suitable for use.

Option 4: A typical erroneous solution, where no fresh air enters and exhaust gas is discharged into the basement, seriously affecting the air quality in the basement and not meeting environmental requirements.