{"id":450754,"date":"2026-01-20T12:56:30","date_gmt":"2026-01-20T12:56:30","guid":{"rendered":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/compile-the-udf-code-and-apply-it-to-the-dpm\/"},"modified":"2026-01-20T12:56:30","modified_gmt":"2026-01-20T12:56:30","slug":"compile-the-udf-code-and-apply-it-to-the-dpm","status":"publish","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/compile-the-udf-code-and-apply-it-to-the-dpm\/","title":{"rendered":"Compile the UDF code and apply it to the DPM."},"content":{"rendered":"

<p>I plan to compile the UDF code based on the content of the image and apply it to DPM. Could you please check if there are any errors in the provided code? The references are as follows.<\/p><p>Xu W, Dong CJ, Li DS. Numerical simulation on influences of wind speed to leaking diffusion of liquid ammonia. Advanced Materials Research. 2015 Jan 27;1073:383-7.<\/p><p> <\/p><p><\/p><div><div>#include “udf.h”<\/div><div>#include “dpm.h”<\/div><div>#include “dpm_mem.h”<\/div><br><div>\/* \u5b9a\u4e49\u5e38\u91cf *\/<\/div><div>#define T_SAT 240.15        \/* \u84b8\u53d1\u6e29\u5ea6 -33°C = 240.15 K *\/<\/div><div>[cite_start]#define LATENT_HEAT 1.37e6  \/* \u6c28\u6c14\u5316\u6f5c\u70ed J\/kg [cite: 66] *\/<\/div><br><div>DEFINE_DPM_HEAT_MASS(multivap, tp, Cp, hgas, hvap, cvap_surf, Z, dydt, dzdt)<\/div><div>{<\/div><div>    int ns;<\/div><div>    Material *sp;<\/div><div>   <\/div><div>    \/* \u53d8\u91cf\u521d\u59cb\u5316 *\/<\/div><div>    int nc = TP_N_COMPONENTS(tp);<\/div><div>    Thread *t0 = TP_CELL_THREAD(tp);<\/div><div>    Material *gas_mix = THREAD_MATERIAL(DPM_THREAD(t0, tp));<\/div><div>    cphase_state_t *c = &(tp->cphase[0]);<\/div><div>   <\/div><div>    real molwt[MAX_SPE_EQNS];<\/div><div>    real Tp = TP_T(tp);      <\/div><div>    real mp = TP_MASS(tp);    <\/div><div>    real molwt_bulk = 0.;    <\/div><div>   <\/div><div>    \/* \u8ba1\u7b97\u7c92\u5b50\u51e0\u4f55\u5c5e\u6027 *\/<\/div><div>    real Dp = DPM_DIAM_FROM_VOL(mp \/ TP_RHO(tp));<\/div><div>    real Ap = DPM_AREA(Dp);   [cite_start]\/* [cite: 63] *\/<\/div><br><div>    \/* — 1. \u70ed\u4f20\u5bfc\u8ba1\u7b97 (\u4fdd\u6301\u539f\u903b\u8f91) — *\/<\/div><div>    real Pr = c->sHeat * c->mu \/ c->tCond;<\/div><div>    real Nu = 2.0 + 0.6 * sqrt(tp->Re) * pow(Pr, 1.\/3.);<\/div><div>    real h = Nu * c->tCond \/ Dp;<\/div><div>   <\/div><div>    \/* Q = h * Ap * (T_gas – T_p) *\/<\/div><div>    real heat_transfer = h * (c->temp – Tp) * Ap;<\/div><br><div>    \/* \u8f85\u52a9\uff1a\u8ba1\u7b97\u6c14\u76f8\u5206\u5b50\u91cf *\/<\/div><div>    mixture_species_loop(gas_mix, sp, ns)<\/div><div>    {<\/div><div>        molwt[ns] = MATERIAL_PROP(sp, PROP_mwi);<\/div><div>        molwt_bulk += c->yi[ns] \/ molwt[ns];<\/div><div>    }<\/div><div>    molwt_bulk = MAX(molwt_bulk, DPM_SMALL);<\/div><br><div>    \/* — 2. \u6838\u5fc3\u903b\u8f91 (\u4fee\u590d\u4e86\u7269\u7406\u9519\u8bef) — *\/<\/div><div>    real evaporation_rate = 0.0;<\/div><br><div>    \/* \u60c5\u51b5 A: \u4f4e\u6e29\u663e\u70ed\u52a0\u70ed (Tp < T_SAT) *\/<\/div><div>    if (Tp < T_SAT)<\/div><div>    {<\/div><div>        \/* \u4ec5\u53d1\u751f\u70ed\u4f20\u5bfc\u5347\u6e29\uff0c\u65e0\u663e\u8457\u84b8\u53d1 *\/<\/div><div>        \/* Eq (9): m * Cp * dT\/dt = Q *\/<\/div><div>        dydt[0] += heat_transfer \/ (mp * Cp);<\/div><div>        evaporation_rate = 0.0;<\/div><div>    }<\/div><div>    \/* \u60c5\u51b5 B: \u6cb8\u817e\/\u6c14\u5316 (Tp >= T_SAT) *\/<\/div><div>    else<\/div><div>    {<\/div><div>        \/* \u5047\u8bbe\u70ed\u91cf\u5168\u90e8\u8f6c\u5316\u4e3a\u6f5c\u70ed (dm\/dt * L = Q) *\/<\/div><div>        if (heat_transfer > 0)<\/div><div>        {<\/div><div>             evaporation_rate = heat_transfer \/ LATENT_HEAT;<\/div><div>        }<\/div><br><div>        \/* \u80fd\u91cf\u5b88\u6052\u5904\u7406\uff1a\u663e\u70ed\u53d8\u5316 = (\u603b\u70ed\u91cf – \u6f5c\u70ed\u6d88\u8017) *\/<\/div><div>        \/* \u7406\u8bba\u4e0a\u6b64\u5904 dydt[0] \u7ed3\u679c\u4e3a 0\uff0c\u5373\u6e29\u5ea6\u4fdd\u6301\u5728\u6cb8\u70b9 *\/<\/div><div>        real latent_heat_term = -evaporation_rate * LATENT_HEAT;<\/div><div>        dydt[0] += (heat_transfer + latent_heat_term) \/ (mp * Cp);<\/div><div>    }<\/div><br><div>    \/* — 3. \u5173\u952e\u4fee\u590d\uff1a\u6e90\u9879\u66f4\u65b0 — *\/<\/div><div>   <\/div><div>    \/* \u83b7\u53d6\u6c28\u6c14\u5728\u6c14\u76f8\u4e2d\u7684\u7ec4\u5206\u7d22\u5f15 *\/<\/div><div>    int gas_index = TP_COMPONENT_INDEX_I(tp, 0);<\/div><div>   <\/div><div>    if (gas_index >= 0)<\/div><div>    {<\/div><div>        \/* [\u4fee\u590d1] \u66f4\u65b0\u7c92\u5b50\u8d28\u91cf\u53d8\u5316\u7387 dydt *\/<\/div><div>        \/* \u7c92\u5b50\u8d28\u91cf\u51cf\u5c11\uff0c\u5bfc\u6570\u4e3a\u8d1f\u503c *\/<\/div><div>        \/* \u6ce8\u610f\uff1a\u5bf9\u4e8e\u591a\u7ec4\u5206\u7c92\u5b50\uff0c\u8d28\u91cf\u5b58\u50a8\u5728 dydt[1 + component_index] *\/<\/div><div>        \/* \u5bf9\u4e8e\u5355\u7ec4\u5206 Droplet\uff0c\u901a\u5e38 dydt[1] \u5373\u4e3a\u8d28\u91cf\u53d8\u5316 *\/<\/div><div>        dydt[1] -= evaporation_rate;<\/div><br><div>        \/* [\u4fee\u590d2] \u66f4\u65b0\u6c14\u76f8\u6e90\u9879 dzdt *\/<\/div><div>        \/* \u6c14\u4f53\u83b7\u5f97\u8d28\u91cf\uff0c\u6e90\u9879\u4e3a\u6b63\u503c (+) *\/<\/div><div>        dzdt->species[gas_index] += evaporation_rate;<\/div><div>       <\/div><div>        \/* \u66f4\u65b0\u6c14\u76f8\u603b\u8d28\u91cf\u6e90\u9879 *\/<\/div><div>        dzdt->gas_mass += evaporation_rate;<\/div><div>       <\/div><div>        \/* \u80fd\u91cf\u6e90\u9879\u901a\u5e38\u7531 Fluent \u6839\u636e mass source \u81ea\u52a8\u5904\u7406\u7113\u6d41\uff0c<\/div><div>           \u82e5\u9700\u663e\u5f0f\u6dfb\u52a0\u663e\u70ed\u4f20\u9012\u7ed9\u6c14\u76f8\uff0c\u53ef\u53d6\u6d88\u4e0b\u884c\u6ce8\u91ca *\/<\/div><div>        \/* dzdt->energy += heat_transfer; *\/<\/div><div>    }<\/div><div>}<\/div><\/div><\/p>\n","protected":false},"template":"","class_list":["post-450754","topic","type-topic","status-publish","hentry"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_forum_id":["291848"],"_bbp_topic_id":["450754"],"_bbp_subscription":["641985","199"],"_bbp_author_ip":["141.11.127.67"],"_bbp_last_reply_id":["450767"],"_bbp_last_active_id":["450767"],"_bbp_last_active_time":["2026-01-20 14:01:43"],"_bbp_reply_count":["1"],"_bbp_reply_count_hidden":["0"],"_bbp_voice_count":["2"],"_bbp_engagement":["641985","199"],"_btv_view_count":["154"],"_bbp_topic_status":["unanswered"]},"test":"24212040751stumail-xsyu-edu-cn"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/450754","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics"}],"about":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/types\/topic"}],"version-history":[{"count":0,"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/450754\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=450754"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}