研究了一维晶格中费曼棘齿-棘爪热机模型.用粒子的概率主方程来描述粒子在晶格中的动力学特性,推导出热流、功率和效率的表达式.通过数值计算分析势垒高度、外力和温比对热流以及热机功率和效率的影响.研究表明:在粒子稳态概率流为零时,存在非零的热流从高温库流入低温库,类似于经典不可逆卡诺模型中的热漏;热漏的存在使得热机的效率远远小于卡诺效率,功率与效率之间为闭合的关系曲线,热机为不可逆热机;对热机性能参数进行优化,可以使热机工作在最优性能状态下.
In this paper, we studiy the Feynman’s ratchet and pawl heat engine in a one-dimensional lattice. The dynamics of the particle is described by a master equation. The expressions of the current, efficiency and power output of the heat engine are derived analytically. The influences of the height of barrier, external load force and the temperature ratio of the heat reservoirs on the efficiency of heat engine are discussed. When the steady-state current is zero, there is a nonzero heat flux transterred from the hot bath to the cold bath, which is similar to the heat leak of the irreversible Carnot model. The curve of the power output versus the efficiency is a loop-shaped one. The heat engine is irreversible and the efficiency is less than the Carnot efficiency. The heat engine can work in optimal operation by optimizing the performance parameters of the heat engine.