甲苯冷却器的设计.docVIP

化工原理课程设计 题目：甲苯冷却器的设计 　　　　　　 姓 名　 　　 张风平 　　　　　　 学 号　　（一）设计题目 （二） 计任务及操作条件 1) 2)冷却介质循环水，入口温度20℃，出口温度自定； 3)允许压降不大于50KPa； 4) 7000小时/年，处理量：95000吨/年； （三） 类型（四）厂址地区（五）设计内容  目录、设计概述····························2.1选择换热器的类型·······················6 2.1.1工作原理··························6 2.1.2换热管布置和排列间距····················6 2.1.3换热器设计的基本原则····················7 2.1.4流体流速的选择·······················7 3、确定物性数据··························7 3.1定性温度·························· 8 4、估算传热面积··························8 4.1热流量····························8 4.2平均传热温差·························8 4.2.1计算平均温度差·······················8 4.2.2计算R和P·························8 4.3传热面积···························9 4.4冷却水量···························9 5、工艺结构尺寸··························10 5.1 管径和管内流速························10 5.2 管程数和传热管数·······················10 5.3计算换热器的实际换热面积和总传质···············10 5.4壳体内径···························10 5.5折流板····························11 5.6折流板数···························11 6. 换热器核算···························11 6.1热流量核算··························11 6.1.1管内表面传热系数···························11 6.1.2污垢热阻和管壁热阻························12 6.1.3计算传热系数KC··························12 6.1.4该换热器的面积裕度···························12 6.2换热器内流体的流动阻力···························13 6.2.1管程流体阻力···························13 6.2.2壳程阻力···························13 7、设计评述·····························14 8、主要符号说明···························15 19、参考文献····························15 1.设计概述热量传的概念与意义热量传递是指由于温度差引起的能量转移在自然界中凡是有温差存在时，就必然从高温处传递到低温处，因此传热是自然界和工程技术领域中极普遍的一种传递现象。 化学工业与的关系化学工业与传热的关系密切。这是因为化工生产中的很多过程和单元操作，多需要进行加热和冷却如：化学反应通常要在一定的温度进行，为了达到并保持一定温度，就需要向反应器输入或输出热量又如在蒸发、蒸馏、干燥等单元操作中，都要向这些设备输入或输出热量。此外，化工设备的保温，生产过程中热能的合理利用以及废热的回收利用等都涉及到传热的问题，由此可见；传热过程普遍的存在于化工生产中，且具有极其重要的作用。无论是在能源，宇航，化工，动力，冶金，机械，建筑等工业部门，还是在农业，环境等部门中都涉及到许多有关传热的问题。它包括:固定管板式换热器、U?型管壳式换热器、带膨胀节式换热器、浮头式换热器、分段式换热器、套管式换热器等。管壳式换热器的核心，其中换热管作为导热元件，决定换热器的热力性能。另一个对换热器热力性能有较大影响的基本元件是折流板（或折流杆）。